Not to sound like an idiot? but what is "Preload" mean?
I am working on a rear end right now.. 3.73 and got some questions about it anyway.
1. I have had two other rearends opened up before and pulled the differential out of a 3.42 setup, but after pulling off the cover of this one I just opened, the differential was totally different, no opening in the middle to get c-clips off the axle, the whole thing is totally sealed? does this mean it's POSI? its jammed up so I can't play with it to find out right now cuz the bearings I belive are shot on the pinion shaft.
I need to get this thing out and can I change these bearings or does someone else have to change these to get them on the right way ro whatever...

 

In simpliest terms, preload is how far into the differential the pinion gear is located. Since the pinion is tapered the farther in it is the harder it pushes against the ring gear. It also determines the contact patch of the pinion and ring gear teeth.

------------------
'87 Bird 350 .060 over 700R4 + Lots more

 

Ok, So the more I tighten down the bolt on the pinion shaft, it will be pulling it back so it wouldn't be pushing as hard against the ring gear correct?

So has anyone seen a differential like the one I am describing where the diff. is just one solid unit??
you can't see the spider gears, if there is any, maybe it is because it's posi?
I haven't played with it cuz It locked up on me.

 

1. Preload refers to the bearings (either pinion, or side bearings). These are taper roller bearings that require some preload in this application. For the side bearings it's .004" tighter than when the carrier just slides in and for the pinion it's set with a torque wrench. You really need a Helm Manual, but this is good: http://sethirdgen.org/10bolt2.htm

2. You should be able to see the spider gears, unless it's a Torsen, which doesn't have any. It has a "paddle" you have to pull out instead of a cross pin, but it's held by the same kind of bolt. Then you will see the C-clips.

------------------
1985 Yellow IROC-Z 5.0 HO, T-5 3.73 Torsen, 4 wheel disks
PFCM pads, GTA wheels, Koni yellows, B&M Ripper, Dynomax

 

Sure it's not a 9 bolt diff?

------------------
88 427 Camaro
12.18 @ 113mph 1.75 60ft
Currently installing 3.73's into my 9 bolt (YES,it is a 9 bolt & YES they are 3.73's, not 3.70. 4.11's to follow soon )
www.koolmeister.com

 

the rearend is a bORGWARNER IT SAYS BORGWARNER ON THE RING GEAR TOO.BUT THERE IS

 

THE REAR END IS A BORGWARNER,IT SAYSBORGWARNERONTHE RING GEAR TO. THERE IS NO WAY TO GET INSIDE THE CASING THAT THE RING GEAR IS CONNECTED TO

 

The borg warner (aka 9 bolt) is different than the 10 bolt. To get the axles out, remove the tires, brakes and rotors. Then remove the 4 nuts/bolts on the square flange behind the axle flange, then the axle will slide out. Once the axles are out, remove the 4 carrier bearing bolts, then the carrier will come out.

Changing gears/carriers is not trival and requires special tools to do it right.

Are you sure about the gear ratio you listed?

email me if you have more questions.

Miles

------------------
88 427 Camaro
12.18 @ 113mph 1.75 60ft
Currently installing 3.73's into my 9 bolt (YES,it is a 9 bolt & YES they are 3.73's, not 3.70. 4.11's to follow soon )
www.koolmeister.com

 

Preload has absolutey nothing to do w/ where the pinion is located. Nor is the pinion tapered. there is a shim on the back of the pinion gear that determines the "depth", wich is usualy .035".

Preload is the amount of tension on the bearings. The more preload, the tigheter the bearings. You tighten the pinion nut to "squeeze" the bearings together, but no matter how tight you go, you will never move the position of the pinion.

The distance between the pinion and ring gear is called "backlash".

And yes, the BORG WARNER rear axle is a whole new beast. They do not use C-clips.

------------------
If you live in Southeastern US, check us out!
South East Thirdgen

GM Master Tech
ASE Master Tech + L1
Savannah, GA

'87 Trans Am
S/D TPI retrofit including functional PassKey,
22# injectors,
Whatever chip I feel like burning,
JET AFPR, Ported Plenum,
TB Coolant Bypass, Custom Cold Air,
SSM SFC, KYB Shocks, Boxed LCAs, Wonder Bar,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
3.73 Posi
4wheel Disc Brakes
Summit 1-5/8" headers, 2.5" Dynomax catback.

Best 1/8: 9.519@72.74

'97 Bonneville SSE

 

OK! Thanks alot guys!
it seems telling you guys that it was a Borg Warner helped you guys to know more about what I was talkin about.. it IS however a 10 bolt not a 9 bolt.. and as far as the gear ratio when you asked am I sure its a 3.73 I can't be 100% certain on that... thats what the guy told me that I bought it off of.. it seemed to run pretty high RPM's compared to the previous 3.23 that was in the car, so I assume it's higher than that.. but I would have to look at it more closely to know for sure.
I appreciate the information! I was getting pretty stumped about how to get these axles out.. cuz I knew I needed to get these stinkin axles out to get that carrier out.

 

A 10 bolt is a GM diff with C-clips, you are counting the bolts on the diff cover, right?


------------------
350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, current red metallic paint. Lots of other stuff...
82camaro

 

Man you guys are amazing.. ok so your right
I miscounted the bolts.. its a 9 bolt!
I thought I counted 10.. but it's 9