Rear Gears ?'s
Subject: [gto2] [gto] Re: Differential Rebuild
Date: Sat, 7 Aug 1999 12:32:56 -0400
From: "Trips"
<< The shop owner that helped the author of that article said that the posi unit could be
rebuilt even though GM says they can't. He didn't get into the details of how to do it in the
article, because he considered it a trade secret. >>
I think the reason that Pontiac claimed that the Safe-T-Track unit could not be rebuilt, is
because it is a cone type. The Chevy type posi's can be rebuilt with new springs and a clutch
pack. The Pontiac unit requires some specialized machining techniques/equipment to resurface
the cones. Obviously, California Differential has figured it out.
<< BTW, my thanks go out to Andy for providing the article. >>
Glad to help.
<< Rick M.
66 GTO Tri-power/4spd
73 GP Model J >>
Andy
'65 coupe, 389, 3-2s, 4-spd
-------------------------------------------------------
<< Having read the article that Rick posted at his site (thanks again), I decided to have
someone rebuild my 3:55 limited slip. Question, though: The article makes a reference that
Pontiac said the clutch assembly couldn't be rebuilt. Any reason to believe that. This guy
(who's a technical consultant with the Cruising Tigers and has been great in the past) has done
several. Still, that Pontiac admonition worries me. Any thoughts?
Thanks.
Bob, Carol Stream
65 Convertible
PS. Thanks, Peter, for your actions. Too bad you've have had to add to your parental
responsibilities! >>
Subject: [gto2] [gto] Re: 3:23 Posi
Date: Thu, 16 Sep 1999 13:26:35 EDT
From: Paul3130
I've always had good luck finding the 8.2 posi's at Gevo's Rears & Gears, a Hemmings advertiser,
ask for John. 315-568-9744 after 6 PM EST. They aren't cheap but they are available.
Paul
<< Does anyone have a clue where I can fine a posi kit in 3:23. Both Richmond and Auburn can't,
or won't, produce one.
Thanks,
Dave Funderburg >>
Subject: [gto2] [gto] Re: 3:23 Posi
Date: Fri, 17 Sep 1999 23:36:00 EDT
From: PONTIAC473
<< Actually the carrier and gears do have something to do with each other.
According to "The Legend" Oct. 97 - there are 3 different 10 bolt carriers.
One covers 2.56 and 2.78, the next is 2.93 3.08 and 3.23, the last one is 3.36, 3.55, 3.90,
and 4.33 >>
Yes but they also make spacers and companies other than Richmond makes gears.
So if you find 1 carrier you can still get other gears for other carriers to fit. My 72 LeMans
has a 3.08:1 carrier and a set of 4.11:1 gear, w/the use of a spacer. So as I said before you
are not out of luck if you have the wrong carrier.
Joey
Subject: [GTO] Dumb Spool Question
Date: Thu, 27 Apr 2000 23:45:50 EDT
From: MycoPhoric
I have a real dumb question about rear end spools..... What exactly is one?????
-THANKS
Steve Rautio
69 LeMans
Subject: Re: [GTO] Dumb Spool Question
Date: Fri, 28 Apr 2000 00:17:42 EDT
From: Corpkilr1
<< I have a real dumb question about rear end spools..... What exactly is one?????
-THANKS
Steve Rautio
69 LeMans >>
Steve.....A spool is like a posi...... Only in the true sense. The axles go into the spool,
which is direct connect to the ring gear. When cornering w/a spool the inside rear wheel will
usually jump, due to the diff. speeds of the inner and outer wheel. Great for the strip........
Usually not so hot for the street. Hope this helps ya out.
Neil -corpkilr-
Subject: Re: [GTO] Dumb Spool Question
Date: Sat, 29 Apr 2000 08:51:08 EDT
From: PONTIAC475
<< Great for the strip........ Usually not so hot for the street. Hope this helps ya out.
Neil -corpkilr- >>
I would like to ad that I drive a spool on the street as do many of my faster friends. And to
tell you the truth I see no difference in cornering than a really tight posi. If you have a
small tired car you will hear a little chirp come from the inside tire on 90 degree or tighter
turns. I don't hear anything, I think it may be because my tires are so big??
Also they waste less HP than a posi does, simply because they are lighter.
Joey
Subject: [GTO] Bad Vibes?
Date: Mon, 08 May 2000 08:56:27 CDT
From: "bill odoherty"
Looking for anyone who has experienced a problem like this:
Have a terrible vibration when DECELERATING in any gear. Checked rear end and u-joints both OK.
Car engine runs great and works great when accelerating, but let off the gas and the vibration
starts. It doesn’t mater if you push in the clutch, shift gears or rev engine. When car comes
to a complete stop it stops. Any Ideas?? Before I pull the tranny (BW T10 4 speed), I think
that that would be the best place to start.
Thanks
Bill6t5GTO
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 08 May 2000 09:54:04 -0500
From: Chris Turner
Did you check the axle bearings? How about the driveshaft? The driveshaft could be out of
balance causing vibrations? Also input shaft on the transmission could cause the same thing.
Do you have trouble ever putting it in gear? Had somewhat the same thing happen to me and it
was a combination of all 3 that solved the problem.
Chris
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 08 May 2000 10:29:15 CDT
From: "bill odoherty"
<< ?1)Did you check the axle bearings? >>
Yes. Actually thought that was what is was first because there was oil leaking out of the pass.
side all over the tire, but it just the inner oil seal on the axle. Bearing was fine.
<< ?2) How about the driveshaft? >>
Both u-joints tight w/no play.
<< ?3) Also input shaft on the transmission could cause the same thing. >>
This one I have not checked yet, but have no problems shifting. I guess the trannys going to
have to come out, it seems like the most logical place to start.
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 8 May 2000 11:49:51 EDT
From: Corpkilr1
Bill,
Might try chkn. the flywheel, all clutch components and the bushings on the main shaft in the
Trans. Hope this helps.
-corpkilr-
P.S. Before ya tear it apart chk. your tranny mount.
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 08 May 2000 15:54:57 CDT
From: "bill odoherty"
Well drove it down to the shop and put it on the lift, mount is in good shape. Pulled the
inspection cover and throw out bearing, clutch and p. plate all look to be in good working
order. The car accelerates great......but let off the gas and put a drag on it and vibration
city.
Bill6t5gto
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 8 May 2000 17:01:13 EDT
From: ROCKTD
Bill,
Have you checked the rear end? Too much back lash or a bad pinion bearing.
Chuck 67,69,72 Goats
Subject: Re: [GTO] Bad Vibes?
Date: Mon, 08 May 2000 19:24:31 -0700
From: rickgto
Sounds like all has been covered except control arm bushings and carrier bearings.
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 9 May 2000 02:07:35 EDT
From: GoatmanPaulC
You might check to see if the rear bushing of the tranny [where the drive shaft is supported]
is worn out causing the drive shaft to flop around.
Goatman
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 9 May 2000 02:10:45 EDT
From: GoatmanPaulC
My Firebird had too much downward pinion angle and did exactly the same thing. When you
accelerate, the pinion is pushed upward and straightens out the pinion angle. When decelerating,
the pinion goes back down and starts binding up the rear u-joint and causes a bad vibration.
Goatman
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 9 May 2000 06:22:03 -0500 (CDT)
From: alan fanning
Here's a WAG: Check the driveshaft to see if weights fell off??
ALF
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 09 May 2000 07:36:27 -0500
From: Chris Turner
If I found oil leaking out of one side of the rear axle, I would consider replacing that
bearing anyway. The load placed on a bearing can not be duplicated by hand. You can easily
rotate a bearing and it look good but it not really be good.
If the transmission is the culprit you usually can tell it by the shifting back down into first
or second. If your driving down the highway and decelerating and shift into neutral does the
vibrating go away? If it does I would be suspicious of the transmission and If not I would be
suspicious of everything behind the transmission.
Just my .0005 cents worth :)
Chris
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 09 May 2000 08:22:20 -0500
From: Chris Turner
You have the answer already. You found grease on the axle with the seal leaking. That’s where
the vibration is coming from or either the inner axle bearing on that wheel. You can’t put the
load that’s put on a bearing or can’t inspect a bearing to tell if its good. 1/1000 of an inch
out of round on one of the bearings and lots of load = lots of vibration.
$1.00 against a donut that’s your answer.
Chris
Subject: Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Tue, 09 May 2000 10:01:57 CDT
From: "bill odoherty"
After pulling driveshaft and getting ready to pull trans. noticed companion flange on rear end
was loose. After further inspection the nut holding the companion flange on had come loose and
was only finger tight.
Question? What is the torque supposed to be on this nut?
I purchased this Rebuilt rear end about a year ago from Sonic Motors out of Minnesota, the only
thing I can Think of is that they must have forgot to tighten it. Luckily I have only put about
500 miles on the car since I installed it.
Thanks
Bill6t5gto
P.S. thanks for all advice on helping me find the problem :>)
Subject: Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Tue, 09 May 2000 12:40:06 -0500
From: Chris Turner
This is what controls your backlash on your rearend. To set it up right, you'll need a new
crush bearing and to set the backlash again. The crush bearing is used to set the depth of the
pinion and also to
maintain a tight pinion.
Chris
Subject: [GTO] Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Tue, 9 May 2000 13:52:26 -0400 (EDT)
From: Konen Tom
Bill, be careful when you tighten that nut it has a lot to do with the gear lash in your
rearend. Usually you have to have the lash checked as you tighten the nut. Too tight and it
rumbles Too loose and it could float when your taking the nut off from the factory the best way
is to count the threads. If your just replacing the seal. You may have to take it to a rear end
shop so its set correctly... I thought Sonic Motors was out of Michigan.
Subject: Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Tue, 9 May 2000 21:02:37 EDT
From: Painzgoat
Is this the rear end with the leaking axle seal? If the seal leaks and the pinion needs reset
you might consider taking it back to the folks you purchased it from and give them the chance
to make things right. After all you paid them for a rebuilt rearend, right?
my two pennies worth.
jim
69 h/t
Subject: Re: [GTO] Bad Vibes?
Date: Tue, 9 May 2000 23:56:48 -0500
From: "Chris Bilich"
I JUST had this EXACT problem 1 month ago, and 2 new U-joints solved it all! My rear joint was
shot, and the front was OK, but I replaced them both. $12 for each joint at AutoZone, and $7.50
at a drivetrain shop to press them in. They recommended balancing the shaft as well, for an
additional $35, but said I should install it first and bring it back if the problem was still
there.
Basically, I didn’t' know how to check the joints properly, but once I had the shaft in my
hands (easiest part on the car to pull!, surprisingly enough) I could see the problem. The
shaking was gone.... Just like you described!
BTW, does it "CLANK" when you're on the brake and shift from N to P and back again.... This was
the sound of the "slack" giving way each time you apply torque and release it.
Chris
Subject: Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Wed, 10 May 2000 08:07:04 CDT
From: "bill odoherty"
Unfortunately I had it shipped to me from them (about 800 miles) also, don’t want pull it out
to send it back, besides the fact that I wasn’t to impressed with their work anyway. Since I
already had to replace the oil seals on the axles. And now the pinion nut comes loose. No one
cares as much about your car as you do. Sometimes ya just lose.
Subject: FW: Re: [GTO] Bad Vibes? Found problem/need answer?
Date: Wed, 10 May 2000 09:38:15 -0500
From: "Bill"
Chris,
I cant find the crush bearing on my parts break down sheet. I see both the inner and outer
bearings. I'm attaching a .Jpg file of the sheet. I don't think that I have one on this rear
end?
<< This is what controls your backlash on your rear end. To set it up right, you'll need a new
crush bearing and to set the backlash again.
The crush bearing is used to set the depth of the pinion and also to maintain a tight pinion.
Chris >>
Subject: Re: [GTO] Bad Vibes?
Date: Wed, 10 May 2000 14:24:37 EDT
From: Goats3
My 65 had a bad rear joint, but you couldn't tell by feel, sight, etc. It would clank
occasionally from P to R. That’s the only way I knew it was bad, until I took it apart.
Kenny L
Subject: [GTO] I got my posi overhauled
Date: Wed, 10 May 2000 21:43:42 EDT
From: Jwroblesk
OK everybody, just got off the phone with Larry Woltzen of California Differential. I spent
about 30 minutes with him discussing Pontiac posi units. He is going to overhaul my unit for
$175 and give me back a factory or better unit. I'll have to let everyone know how it works
when I get it back together, but if it's anywhere close to what he says, I will be very
impressed. Got a 5 year warranty with it also. If you need your Pontiac posi unit overhauled,
this is the guy. His phone # is 510-490-6483.
Joe
67 GTO
Subject: Re: [GTO] I got my posi overhauled
Date: Thu, 11 May 2000 09:56:03 -0400
From: Dave Funderburg
Joe,
Art Houser in PA does GM rears. Get his number at http://www.rearman.com Got a posi for my 69
GTO Convertible from him. You might want to check him also.
Dave
Subject: Re: [GTO] I got my posi overhauled
Date: Thu, 11 May 2000 10:15:49 EDT
From: Jwroblesk
Hi Dave,
I called Art Houser twice and both times he said he would get back to me-but he never did. I'm
glad I got my original overhauled though because it was a 4 pinion and both Art and Larry said
the 4 pinion is indestructible. Art told me it would handle up to 700 horse power.
Joe
Subject: Re: [GTO] I got my posi overhauled
Date: Thu, 11 May 2000 12:34:53 EDT
From: Green68gto
I'm in the 510 area code, so this guy must be close to me. Where exactly is he located? I've
been thinking of getting my posi rebuilt and was going to have a local mechanic do it. I'd be
more interested in a specialist working on it. Do you know if it has to be out of the car?
Please let me know how it comes out.
Ken
'68 GTO
Subject: Re: [GTO] I got my posi overhauled
Date: Thu, 11 May 2000 15:09:18 EDT
From: Jwroblesk
Hi Ken,
He's at 44255 Fremont Blvd., Fremont, CA. This is the guy who was highlighted in Pontiac
Performance magazine about 10 years ago. I had a heck of a time finding him because he moved. I
would definitely let him do it over a regular mechanic. Go talk to him-you'll be convinced.
Joe
Subject: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 00:57:08 EDT
From: RMH16
Hi everyone,
Well every time I ask a question. I get the correct answer. So here is my next problem.
I have a 67' GTO and I knew the rear end was wrong when I bought it. Well, it turns out it
is a 12-bolt Chevy. The shop that checked it out, would love to do a trade with me. He told me
all I need to do is find out what type of rear end was the most common for a 67’ GTO, and he
will locate one for me.
So, could anyone help me out with an answer. I hope I gave you enough info, I do have a
Turbo 400 tranny if you need to know.
Thanks, and I look forward to hearing from you all !!
Rob-67'GTO
Subject: Re: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 02:08:26 EDT
From: Kuchila
I can go out tomorrow and look at mine if that will be of any help. Just exactly do you need to
know. Codes?? Length from backing plate to plate??
May even be able to get info for you from GTO Restoration Guide.
later
kuchila
Subject: Re: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 06:08:30 -0700 (PDT)
From: Brian Smit
Rob,
‘67 4-spd. standard 400 4bbl, engine code WT- standard axle is a 3.55 w/o air and 3.23 w/air.
The axle identification codes would be - 3.55=WH for standard axle and YH for the safe-t-track.
The 3.23 would be WF for standard axle and YF for safe-t-track.
The Turbo 400 would be engine code YS and have a 3.36 w/o air and a 2.93 w/air. The axle ID
codes would be WG for the standard axle and YG for the safe-t-track. The 2.93 would be codes WD
for the standard and YC for the safe-t-track.
The axle code is stamped on the axle housing on the passenger side, just right of the pumpkin.
Most common...IMHO...3.55/3.36
Hope this helps.
Subject: Re: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 10:06:44 -0500 (CDT)
From: alan fanning
There's a reason why they'd "love" to do a trade with you. The 12 bolt is probably a stronger
rear than the stock 10 bolt. Is there some overriding reason why you want to change? Unless
this is a "perfect" type resto... I'd personally leave the 12 bolt in it and dare anyone to
notice the difference!
ALF
Subject: Re: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 13:03:11 -0500
From: Terry Nixon
I, too, would love to trade with you and it just so happens I have an original 10-bolt '67 rear
with 3.55 open gears out of my own GTO. Not quite the "correct" one for an automatic, and it
needs some seals and some brake work but hey, if you don't want the 12-bolt... Kidding aside,
don't let them cheat you on that 12-bolt. 10-bolts are under every pre-'70 Tempest, but
12-bolts are not. To my mind, there would be NO reason to change it unless you found the EXACT
code for your car. Unless there is severe wear or something. Still, 12-bolts for A-bodies are
like ice water in hell...
Subject: Re: [GTO] 67' rear end size ?
Date: Wed, 26 Jul 2000 14:30:38 -0500
From: Chris Turner
I just want the 4.11's :) The 2.78's in my GTO is wayyyyy to slow off the line but 142 mph is
obtainable just ask the Local Alabama State Trooper that pulled me over.
Chris
Subject: Re: [GTO] 67' rear end size ?(NC)
Date: Wed, 26 Jul 2000 18:44:58 -0500
From: "Dirk Denzin"
<< What is so special about the 12 bolt. Have one under my 66 - Came with it.
Don't know what it is off, but I would gladly hand it over for a correct 10 bolt 3.55 posi. In
fact I have a posi for a 64/65 GTO under my bench but it has the wrong gearing in it. Just
haven't put together the $ to have it rebuilt. >>
1) They are allot stronger!
2) You can get any kinda part to rebuild/beef up you want. Axles, C-Clip eliminator kits,
Gears, Center sections etc. etc. parts are easy to get!!
3) Because of 1 and 2 they are more valuable, do not swap even up they should give you some
cash in the deal!!
Why get rid of the 12 bolt? Its a better rear end that is easier to get parts for to rebuild if
necessary and it will handle any engine you can put in front of it with street tires on it!
Dirk
Subject: [GTO] rear end
Date: Tue, 1 Aug 2000 23:38:01 -0400
From: "jharakal"
Hi all, while trying to find out more about my 67 GTO I got my PHS info in, it says the car has
2:93 gears with air and a Turbo tranny, no mention of safe-t-track, looked under the car, it
has a 10 bolt cover and a metal tag, says to use some type gear oil, how do I find out what I
really have?
thanks .....jbh
Subject: Re: [GTO] rear end
Date: Mon, 14 Aug 2000 00:39:00 EDT
From: Corpkilr1
<< I got my PHS info in, it says the car has 2:93 gears with air and a Turbo tranny, no mention
of safe-t-track, looked under the car, it has a 10 bolt cover and a metal tag, says to use some
type gear oil, how do I find out what I really have?
thanks .....jbh >>
JBH,..........The metal tag usually says "limited slip" which is posi. To find out, get
the rear end up, and turn the driveshaft, the wheels will both turn equal if it is. The ratio
can be found by marking the driveshaft and turning the wheel 1 revolution, and counting how
many times the driveshaft goes around. Or you can pull the cover look inside, and see what's
stamped on the ring gear.
-corpkilr-
Subject: Re: [GTO] rear end
Date: Mon, 14 Aug 2000 17:05:41 -0500
From: Terry M Nixon
The metal tag is what the factory used to notify service personnel that the rear needed a
special friction additive. This was used only in locking differentials: "Posi-Traction",
"Safe-T-Track", whatever. If you have the tag, you probably have a Safe-T-Track rear. Question:
where on your PHS docs does it show the gear ratio? Mine doesn't have it on there, just a
number in column 73 that I can't decode. If your PHS docs have the letter codes your car was
built with, the code for a '67 open 2.93 is WD. A limited-slip is YD. Now for the tricky bit:
finding the code on the rear. Two letters 1/4 inch high, either on the top front or top rear of
the axle tube, either on the left or on the right. Hopefully it's not too rusty or greasy or
dirty. Usually you have sand most of the tube to find it. THEN you need to jack up the car,
spin the wheels, count the number of turns, and see if it's the one the code tells you it is.
One wheel on the ground, trans in neutral. If you can turn the lifted wheel by hand, it's
likely not posi, but it could be a really worn out one. If you find you have an open rear, hold
one wheel and turn the lifted one TWO turns. Count the driveshaft turns directly. Should be
nearly 3. Usually the opposite wheel turns too easily to count right; this is why you hold one.
Spider gears affect the driveshaft turns; this is why you turn the loose wheel twice. With both
wheels off the ground, open rears turn opposite directions, lockers the same direction, because
the transmission friction is greater than spider gear resistance, but lockers are greater yet.
If it won't turn, jack up both sides. Turn the wheels ONE turn. They should both go the same
direction. Count the number of turns the driveshaft makes. Should be almost 3.
Terry
Subject: Re: [GTO] rear end
Date: Tue, 15 Aug 2000 14:46:52 CST
From: "Maj. Frank Burns"
<< and what ratios are considered "highway gears" and what is the alternative? >>
"Highway gears" are numerically lower gears that require fewer engine RPM per wheel RPM. So, if
you're turning lots of wheel RPM (at 70 MPH, for example) the highway gears keep the engine RPM
lower.
<< Compared to my new car with overdrive, it always seems like my Goat needs to upshift a few
more times, on the highway or street. >>
My truck has a 4-speed overdrive automatic and if I've driven it for a few days and switch to
the Trans Am (TH350) I keep waiting for that nonexistent 3-4 shift. The TH200-4R swap will take
care of that. ;^)
Brad
Subject: [GTO] Rear Gear Help
Date: Wed, 30 Aug 2000 08:31:16 -0400
From: Chuck
I need gear help!! I had my 400 rebuilt this spring and now have a surging problem. Keep in
mind that the surge did not exist before the cam change. The car specs are a follows:
Block 68 400
Cam OEM spec's 041
-Advertised Duration -INT 308 EXH 320
-Duration @.050 Lift- INT 231 EXH 240
-Valve Lift- INT .470 EXH .470
Rockers- 1.65
Transmission - M22 Rock Crusher
Intake Manifold - Stock- Cast # 9794234
Carb- Q-jet
Heads Stock - 15#
Tire size- 215/70R/14
This car is a show car that I like to drive, I would like to a do a little dragging with it
(not much) I think the rear ratio is either 3.08 or 3.23.
Any help would be great.
Thanks Chuck
Subject: RE: [GTO] Rear Gear Help
Date: Wed, 30 Aug 2000 07:38:53 CST
From: "Maj. Frank Burns"
<< I need gear help!! I had my 400 rebuilt this spring and now have a surging problem. Keep in
mind that the surge did not exist before the cam change. The car specs are a follows:
Block 68 400
Cam OEM spec's 041
-Advertised Duration -INT 308 ExH 320
-Duration @.050 Lift- INT 231 EXH 240
-Valve Lift- INT 470 EXH 470
Rockers- 1.65 >>
My initial thought is that the Q-Jet power piston spring is too stiff. The 041 cam will cause
lower engine vacuum and the spring may be causing the power system to cut in and out. You might
want to consider a softer spring.
What's the Q-Jet number? I'll try to dig up the p/n for the spring used on RA II/IV cars.
Brad
Subject: RE: [GTO] Rear Gear Help
Date: Wed, 30 Aug 2000 09:07:59 -0400
From: Chuck
<< My initial thought is that the Q-Jet power piston spring is too stiff. The 041 cam will
cause lower engine vacuum and the spring may be causing the power system to cut in and out. You
might want to consider a softer spring.
What's the Q-Jet number? I'll try to dig up the p/n for the spring used on RA II/IV cars.
Brad >>
Brad the Q-jet # is 29268
Subject: Re: [GTO] California Differential
Date: Wed, 12 Apr 2000 09:01:01 -0700
From: "Gary L. Travis"
Joe and All,
The new # for California Differential is (510) 490 - 6483 Hours are M-F 10 - 6 PST. He's on
vacation right now until May 1st at 10:00 AM.
Gary T.
64 GTO Htp.
75 455 Grand Am
Jwroblesk wrote:
<< Anybody on the list know where Larry Woltzen of California Differential might be? His phone
is disconnected and a web search provided no help.
Thanks,
Joe >>
Subject: [GTO] '70-'72 GTO/8.2 Safe-T-Track
Date: Tue, 5 Sep 2000 15:07:10 EDT
From: Rwchumley
California Differential has an ad in Hemmings for Safe-T-Track rear ends. I need to upgrade the
3:23 open rear in the '71 GTO conv. They wanted $475.00 plus shipping for a '70-'72 rebuilt 4
pinion 8.2 carrier. Is this about what they run price wise around the country? Also, anyone on
the list happen to know of another source for these? Thanks
Bob Chumley
Subject: Re: [GTO] '70-'72 GTO/8.2 Safe-T-Track
Date: Tue, 5 Sep 2000 19:39:15 EDT
From: Jrmoseley
Bob,
Never heard of these guys but $450 is better than $1000 for new ring and pinion and carrier.
Send us the phone # for them, but I bet new gears are always better than re-built. Do you have
to send your old one in for the rebuild?
Jim
67GTO
Subject: Re: [GTO] '70-'72 GTO/8.2 Safe-T-Track
Date: Wed, 6 Sep 2000 09:17:44 EDT
From: Rwchumley
<< Bob
Never heard of these guys but $450 is better than $1000 for new ring and pinion and carrier.
Send us the phone # for them, but I bet new gears are always better than re-built. Do you have
to send your old one in for the rebuild?
Jim
67GTO >>
The number for California Differential is 510-490-6483. They have an ad in the Sept. ‘00
Hemmings on page 6710. The cost of $475.00 plus shipping is for a rebuilt 8.2 4 pinion Safe-T
-Track unit only, no gears. I called around the KC area to check pricing on having it installed
in the rear of my car. Around $150.00 to $175.00 labor plus whatever additional parts are
needed.
Bob C.
Subject: Re: [GTO] '70-'72 GTO/8.2 Safe-T-Track
Date: Thu, 7 Sep 2000 20:48:57 -0400
From: "Chris Smetana"
<< The number for California Differential is 510-490-6483. They have an ad in the Sept. ‘00
Hemmings on page 6710. The cost of $475.00 plus shipping is for a rebuilt 8.2 4 pinion Safe-T
-Track unit only, no gears. I called around the KC area to check pricing on having it installed
in the rear of my car. Around $150.00 to $175.00 labor plus whatever additional parts are
needed.
Bob C. >>
Hmm, not bad. But, for I believe $369 or $399 you can get a brand new Auburn unit. That's what
I'm planning on doing to the '66 3:55 open I have. If I ever get money to do it.
Chris
2 66 GTOs, 1 Calif. hardtop under restification, 1 rusted body going to the big junkyard in the
sky
Subject: Re: [GTO] '70-'72 GTO/8.2 Safe-T-Track
Date: Fri, 8 Sep 2000 09:32:46 EDT
From: Rwchumley
<< Hmm, not bad. But, for I believe $369 or $399 you can get a brand new Auburn unit. That's
what I'm planning on doing to the '66 3:55 open I have. If I ever get money to do it. >>
According to California Differential the 4 pinion 8.2 is stronger than the Auburn. Also, is
there an Auburn for the 3:23 ratio?
Bob C.
Subject: Re: Axle code was: [GTO] Billing History Question
Date: Thu, 7 Sep 2000 07:54:33 -0400
From: "The Chebs"
<< The quick way is to go underneath your car and search along the back side of the rear axle
tubes for the stamped 2 letter code. >>
I have looked and looked and looked for this code on my car and cannot find it. It is either:
not there (bummer, means a new rear axle somewhere in the past 32 yrs. and therefor a lot
harder for me to get an axle ratio) or, it is so small my rapidly aging eyes simply are
overlooking it. Can anyone tell me approximately how big (small?) these letter codes are? One
inch high?
Half and inch?
Thanks
Kurt
67 Conv
Subject: RE: Axle code was: [GTO] Billing History Question
Date: Thu, 7 Sep 2000 08:41:29 -0400
From: CharlesB
More like a 1/4" if that. I found mine by using medium grade krokus cloth & then the strongest
degreaser cleaner I had. Even then, the stamped letters probably won't be so clean cut in
appearance. Mine were very 'worn in' looking. Barely legible. When I finally got mine readable
I was actually afraid to keep polishing that spot because they were barely readable then & I
didn't want to wear down the metal anymore! The angle of the droplight is critical too. Get
comfortable down there cause it might take a while. IIRC they're stamped on the left tube?
Somebody check me on that?
CB
Subject: Re: Axle code was: [GTO] Billing History Question
Date: Thu, 7 Sep 2000 13:35:51 EDT
From: ARayman
I just did this last week on a 67 I have.. I had always found them on the driver side tube, on
the back.. A website told me to look on the right hand
tube. It was not there, it was on the
driver side about halfway between backing plate and differential.
This car had undercoating, so all I had to do was scrape with a spatula...
Found it in about 2 minutes. Code was stamped clear, and metal was clean and shiny due to
undercoating.
Subject: [GTO] Re: Axle code
Date: Thu, 7 Sep 2000 12:41:25 EDT
From: Green68gto
If memory serves me correctly, the letter code is stamped in the left tube from 64-68 and the
right tube from 69-up. I might be mistaken though. I've been pretty lucky with my cars, they've
all had relatively clear stampings.
All it took was a few swipes with a ScotchBrite, a couple squirts of 409, and a flashlight.
When all else fails you can do it the old fashioned way. Put your car up in the air and
disconnect the driveshaft. Then count the number of rotations your driveshaft yolk makes in
comparison to your wheel. I'm sure there are several cars out there that have the correct axle
housing, but someone has swapped gears over the years.
Ken
'68 GTO
Subject: [GTO] recurring axle leak- bad vent?
Date: Thu, 14 Sep 2000 03:27:18 GMT
My pass. side axle seal is drooling 90 weight onto my brake drum. This is a surprise, since I
just re-sealed the damn thing 4 months ago and put new brake shoes on it. Could it be a bad
seal job, or a bad axle vent? The vent is visible on top of the tube on the pass. side, and it
looks like its broken.
If I want to replace it, anybody know where to get a new one?
Press it in or screw it in... Or maybe buy it dinner first?
The stupid little problems stump me every time.
Jim O.
68 GTO with standard axle
Subject: Re: [GTO] recurring axle leak- bad vent?
Date: Wed, 13 Sep 2000 23:47:59 -0400
Jim,
I had a similar problem with my 69 LeMans after pulling the axle shaft and replacing the
wheel bearing and oil seal, 2 months later I noticed gear oil in the rear wheel. When I
installed the seal, I lubed it with gear oil, but a friend of mine told me it was best to use
bearing grease and lube the axle shaft and the seal well. He said just using gear oil may dry
up before the seal breaks in and ruin the seal. I installed a new seal, this time using bearing
grease and it has been great for nearly 2 years now. May have just been a coincidence.
Good luck!
Ted Schultz
69 LeMans Convertible, 400, TH350
Subject: Re: [GTO] recurring axle leak- bad vent?
Date: Thu, 14 Sep 2000 00:43:55 EDT
<< My pass. side axle seal is drooling 90 weight onto my brake drum. This is a surprise, since
I just re-sealed the damn thing 4 months ago and put new brake shoes on it. Could it be a bad
seal job, or a bad axle vent? The vent is visible on top of the tube on the pass. side, and it
looks like its broken.
If I want to replace it, anybody know where to get a new one?
press it in or screw it in... or maybe buy it dinner first?
The stupid little problems stump me every time.
Jim O.
68 GTO with standard axle >>
There's no chance it has a Chevy c-clip rearend in it is there? They have axles that ride on
roller bearings [as opposed to bearings pressed on the axle shaft like Pontiac does it] and it
is very common for the axle shaft to wear out and create a leak as you describe. Pontiac rears
generally don't have this problem. You can tell by pulling the break drum off and if you can
pull the axle out simply by removing the four bolts that hold the bearing retainer in place,
then you have the Pontiac type. If you have to get into the rearend housing and pull a pin to
remove c-clips that hold the axle in, then you have a Chevy type.
Goatman
Subject: Re: [GTO] recurring axle leak- bad vent?
Date: Thu, 14 Sep 2000 12:49:03 GMT
<< if you can pull the axle out simply by removing the four bolts that hold the bearing
retainer in place, then you have the Pontiac type. If you have to get into the rearend housing
and pull a pin to remove c-clips that hold the axle in, then you have a Chevy type.
Goatman >>
There's no C-clip. I had both the axles out when I tried to seal it last time. Actually, I did
not replace the seal, because it didn't feel rough and didn't look broken. I think I WILL
replace it this time and lube it with grease, like Ted recommended. Any reason I should try to
replace the plastic vent thing??
thanks
Jim
Subject: Re: [GTO] recurring axle leak- bad vent?
Date: Fri, 15 Sep 2000 01:20:03 EDT
<< There's no C-clip. I had both the axles out when I tried to seal it last time. Actually, I
did not replace the seal, because it didn't feel rough and didn't look broken. I think I WILL
replace it this time and lube it with grease, like Ted recommended. Any reason I should try to
replace the plastic vent thing??
thanks
Jim >>
I would just make sure it is clear and not plugged up. Ted had a good recommendation, so that
sounds like the ticket.
Goatman
Subject: [GTO] Rear end
Date: Mon, 6 Nov 2000 00:16:48 EST
From: CLOZEM
Hey gang, I want replace my 2.93 rear end with a 3.55. Can I use the same carrier?
What's my mission?
Thanks,
Scott
'67 GTO Conv.
Subject: Re: [GTO] Rear end
Date: Tue, 7 Nov 2000 01:10:43 EST
From: GoatmanPaulC
<< Hey gang, I want replace my 2.93 rear end with a 3.55. Can I use the same carrier?
What's my mission?
Thanks,
Scott
'67 GTO Conv. >>
The 3:55's will not work with the 2:93 carrier. You will need, what I believe is called, the #2
carrier. It goes from either 3:08 or 3:23 -3:55. Any corrections people?
Goatman
Subject: RE: [GTO] Rear end
Date: Tue, 7 Nov 2000 09:54:27 -0500
From: CharlesB
<< The 3:55's will not work with the 2:93 carrier. You will need, what I believe is called, the
#2 carrier. It goes from either 3:08 or 3:23 -3:55. Any corrections people?
Goatman >>
Yeah, I forget the exact ratios from 1 series to the next too, but I know with Chevys the
2:93's are in a '1' series carrier. For 3:55's you'd need a '2' series carrier. There's 4
different 'series' of carriers total with Chevy. I don't know how a BOP rear compares to this.
I know a guy who once had in his GTO a (aack!) Chevy 12 bolt '2' series carrier & put in
3:90's, which are '3' series gears. North Jersey Performance did the rear & all they had to do
was apply some type of shimming technique. Rear worked just fine. Seemed strong too.
CB
Subject: Re: [GTO] Rear end
Date: Tue, 07 Nov 2000 15:08:23 GMT
From: "Pete Judge"
I am sure your right Goatman, been there and even the axles change, they get beefier.
Pete
70 Judge
Subject: [ChevellePages] calculating rear end gears
Date: Fri, 09 Feb 2001 16:48:00 -0800
From: Dan Cobb
There must be an easy formula to calculate the gears (non-posi) by jacking up one rear wheel,
putting the tranny in neutral, marking the tire, spinning the driveline and countign the
revolutions of the tire no?
I'm trying to see what the rear gears are without taking it all apart.
I'm really trying to calculate the speedometer error, but I need to know the rear gears, tire
diameter and engine RPM in order to do so. Probably need to know the ratio of the tranny as
well, but I figure it is typical of a TH350. Are there any different output ratios for a 350
that would make a significant difference to the calculation?
Any insight is appreciated.
Thanks,
Dan
++++
Subject: RE: [ChevellePages] calculating rear end gears
Date: Fri, 09 Feb 2001 19:14:20 CST
From: Riff Raff
<< I'm trying to see what the rear gears are without taking it all apart. >>
I'm not trying to be a smartass (it comes naturally), but if you've never changed the gear oil
then you can kill 2 birds with 1 stone; the info you're after is engraved on the ring gear and
is easily read with the cover off.
If you don't want to get all gear-oil-stinky, raise the rear so that both tires are off the
ground. Put the transmission in Neutral and give 1 tire a test spin. If the other tire turns
in the opposite direction then you most likely have an open diff, although a worn-out posi
sometimes will produce the same effect. A functioning posi (limited slip) will cause the other
tire to turn in the same direction as the tire you're rotating.
If you're confident you have a non-posi diff then rotate the tire 2 revs and count the number
of driveshaft revs. If it's a posi then rotate the tire only once. Throw a ":1" behind the
number of recorded driveshaft revs and that's most likely your rear gear ratio.
Of course, use jackstands when raising your Chevelle's rear off the ground.
Brad
Subject: Re: [ChevellePages] calculating rear end gears
Date: Fri, 09 Feb 2001 21:56:06 EST
From: rick schaefer
dan
There is a code stamped into the rear axle tube that will tell you the ratio. IF the gears
haven't been changed since it was new. If you are reasonably sure that the gears haven't been
messed with, you can post the letters/numbers here and some one should be able to decode.
The code is STAMPED into the front of the passenger side axle tube, about 3-10 inches away
from the center section. The stamped letters/numbers are small (1/4 inch) and are similar to
the engine ID stamping. You will need some rags, degreaser, elbow grease & plenty of light.
To calculate speedo error you can travel along any interstate or other highway with mile
markers. Take a zero reading off your speedo as you pass a marker, drive at least 10 miles and
take another reading.
For a VERY good explaination go to:
http://links.chevelles.net/links/WorkShop/General_Info/ Page down to the "SPEEDOMETER GEAR
SELECTION" link. That is Fred Aldrichs page. He is a retired GM engineer & has a great
explaination. He also lists all the speedo gears (with GM Part #) availalble.
There is also a "SPEEDOMETER RECALIBRATION" link that has some good info.
rick (Abilene Texas)
72 El Camino TPI 350/700r4
ACES #00140
TEAM CHEVELLE #00038
http://members.home.net/jimmy4/rick72elky.html
Subject: RE: [ChevellePages] calculating rear end gears
Date: Fri, 09 Feb 2001 21:10:28 -0800
From: Dan Cobb
Smartass or not Brad, you've made a pretty good point about checking/changine the gear oil.
I'll put it on my list.
Dan
++++
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