Auburn LSD rebuild help

[rhouse21]

OK. After ~14 years and ~230,000 miles, it looks like my old Auburn LSD is completely non functional. I've been told that the problem is probably just my springs being worn out and that I should be able to buy a rebuild kit to get everything back in working order. Has anyone been suscessful in finding such a kit? I haven't been able to find anything usesful on line that looks like it might work.

Help?

[Bird_Of_Prey]

Re: Auburn LSD rebuild help

Have you tried contacting Auburn?

[rhouse21]

Re: Auburn LSD rebuild help

Actually, after I posted this, I decided to try one more time. Auburn's O.E.M section of their web site is essentially blank, but their aftermarket section has part #542046 listed for our cars. Jegs.com also has this part available (listed as part# 109-542046) and has a variety of rebuild items for that part number.

The question is: is this aftermarket LSD the same one our cars shipped with?

The next question is: is it even worth it to rebuild this unit when I can get a 98-02 Z-28 Torsen unit from a junk yard?

Any thoughts?

[Mark42]

Re: Auburn LSD rebuild help

Actually, after I posted this, I decided to try one more time. Auburn's O.E.M section of their web site is essentially blank, but their aftermarket section has part #542046 listed for our cars. Jegs.com also has this part available (listed as part# 109-542046) and has a variety of rebuild items for that part number.

The question is: is this aftermarket LSD the same one our cars shipped with?

The next question is: is it even worth it to rebuild this unit when I can get a 98-02 Z-28 Torsen unit from a junk yard?

Any thoughts?

The problem with your Auburn is more to do with worn clutches, than weak springs. Differential clutches are like brake pads or clutch disks, they wear with use. Eventually just wear so thin that the springs can not apply enough pre-load to make them catch/lock. The springs may also have lost some effect, especially over so many miles of heat/cool cycles (very bad for springs).

The Torsen unit will work just fine, but is not built to handle more than the daily riggors of the z28. The pros: Cheap, fairly quiet, work really well in the rain (no preload, so rear is not pre-disposed to locking on wet slippery surfaces when turning under normal throttle), no chatter, and locks when it should. Reduced tire wear due to no clutch/spring preload. Cons: Extended high rpm clutch dumps will destroy the unit in short order. A salvage yard unit is always questionable as to condition. The Torsen does need posi additive or it will run noisy. Search on "rusty noise" in torsens.

A nice upgrade from the Torsen is the Eaton Detroit Truetrac all gear differential. Stronger than the Torsen, better design, quicker lock under load (higher torque bias ratio), runs silent in all but the most extreme torque differentiating conditions and comes with this nice coating of machine oil so it looks really cool sitting on your kitchen counter: :banana:



I have been running the Eaton unit since January 2010 with no problems. Works exactly as advertised, wonderful in the rain and snow. And leaves these really cool EVEN peal out marks when you hammer the throttle. But this too will eventually fail if you go to the track often. Basically, anything you put in the F-body rear housing will fail if you go to the track often.

My guess is rebuilding the Auburn is the most economical solution, because 1) YOU pull the unit, rebuild (or have a shop rebuild), its cheaper than a NEW unit. 2) You reinstall with same shims and gears knowing it will have correct gear wear pattern. No setup needed. You save up to $400 on new differential install labor. 3) It worked for the first 100,000 miles (I bet the clutches were worn by then, now its just an open rear) and you should get another 100,000 out of it.

Don't forget to add in the cost of new bearings and races for which ever way you go. At the milage you have, bearings should be replaced. Save the shims and tie wrap each side together as a group and LABEL them so you know which side they go back on.

Just my thoughts, hope this post helps.

Update:

Just remembered something: Call around to the privately owned TRANSMISSION shops and ask now much to rebuild your OE Auburn unit if you bring it in. I bet the price is not more than 1 hour labor plus parts. Where I live, its the independant trans shops that do all the trans/drive shaft and rear axle work. Avoid chain stores unless you know the manager PERSONALLY!!!!

[ssms5411]

Re: Auburn LSD rebuild help

I think GM makes a rebuild kit for either the Torsen or the Auburn unit, I would have to ask the Parts Dept.

[rhouse21]

Re: Auburn LSD rebuild help

Thanks for the replies. This is very good advice!

BTW: That Eaton does look pretty sweet.

I guess I'm a little torn. On one hand, this car is my baby. I'm the original owner and it is still my daily driver, so I want everything to work correctly. On the other hand, I've kinda outgrown my raging burnout days and there's really no way to restore full LSD functionality without a good lay-out of cash. Tens of thousands of camaros are out there perfectly happy with open diffs.

...Then again, I do want to be able to drive in the winter and in the wet without having to worry about all the open-diff drama.

[Mark42]

Re: Auburn LSD rebuild help

How about getting the entire axle assembly w/same gear ratio and swap the whole rear? The whole rear usually runs about $150 or so with the Torson diff, and if you can do the work, its probably the cheapest way to go.

For a daily driver, its a good option. You get to keep the LSD, and if you are not dumping the clutch at 6K, it will get the job done.

[Meemperor]

Re: Auburn LSD rebuild help

I've got a brand new Auburn Pro posi for 28 spline axles I can let go.

[rhouse21]

Re: Auburn LSD rebuild help

How about getting the entire axle assembly w/same gear ratio and swap the whole rear? The whole rear usually runs about $150 or so with the Torson diff, and if you can do the work, its probably the cheapest way to go.

For a daily driver, its a good option. You get to keep the LSD, and if you are not dumping the clutch at 6K, it will get the job done.

$150? Maybe I need to move by you. My nearest salvage yard wanted ~$600 for a compatable rear end.