LSD Diff backlash
 

I have a driveline slack when I accelerate and decelerate.
So far I have done these.
1. Replaced the CV axles. Used axles have no radial play.
2. Moved the center bearing forward by 1/4 inch
3. Replaced the guibo.
4. U-joints on drive shaft are good.
I can still feel the driveline slack.

It looks like the slack is inside the diff with LSD.
238k miles on body.

Is it possible the clutches and dog ears are worn or have worn the grooves where the dog ears reside in the LSD carrier?

Where can I get LSD clutch rebuild kit?
What is the diff size?

Thanks.

I am going to check the differential bushing tomorrow. It could be deteriorated.

Took the diff cover off to replace bushing. Bushing is deformed and causing diff housing up/down movement.
I replaced it with new Powerflex urethane type bushing.
I am amazed. No more clunking in the rear.
Although the diff is bolted to the subframe, the sheet metal is so thin it is flexing as I raised the diff with a floor jack while aligning the bushing to the hole.
One problem solved.
Subframe bushing next.

which bushing did you end up going with? im about to do this same job on my ti and i wanted to go poly, but wasnt sure about density etc...

He mentioned he used a powerflex.

I'm getting some clunking sound when I take off from a dead stop. Wonder if the problem is the same as yours. Getting rid of the car in the near future, so not a big deal

Answer to the questions:
1. I used Powerflex urethane diff bushing
2. Clunking when taking off from dead stop could mean a lot of things
- Loose CV axles
- Loose propeller shaft splines and u-joints
- Deteriorated guibo
- Dual mass flywheel loose or separated
- Deteriorated Diff bushing
- Play in transmission input and output shafts
- loose center bearing

If you are getting rid of the car, just be honest to the buyer and just pass them on to the next owner.

If you are looking for diff rebuild parts http://www.bimmerdiffs.com/ is your source. Jonathan just rebuilt the diff for my Club Sport. I have not installed it yet but I have seen him work and he knows what he's doing.

I already sent an inquiry to bimmerdiffs last month.
2-clutch clutch refresh kit, $240.99

Jonathan Thayer
Oct 16 (3 days ago)
The 318Ti uses a 168mm differential. Typically they take the 23-tooth clutches but sometimes they take 21-tooth clutches. There is no way to know for sure without taking it apart. Because of the size of the differential we only offer the 2-Clutch Stock Refresh Kit which can be found at the following link: http://www.bimmerdiffs.com/collectio...ck-refresh-kit

Please let us know if you have any other questions!

I bought a used open diff and swapped them this weekend.
Wow ! The car is transformed. Driveline is a lot tighter.
Basically even the remaining slight thug when taking off is gone.

I will open up the LSD diff and find out which parts failed and need to be replaced.

I started opening my lsd diff to inspect for worn components.
I will disassemble the diff and look at the clutch pack next weekend.

Decided to open up the LS diff.
I have the 23T clutch on the stock TI LSD.
It is very worn and the dog ears are loose on the slot which explains the slack or backlash.
I will save up and order the stock refresh kit.

I've been reading up on this topic lately since I just bought a 4.44 LSD and want to convert it to a 3.45 LSD.

I sent an email to Ireland Engineering and got the following information. The clutch discs and the dog ear plates are the same in all 168mm differentials after the E21. Therefore, I believe that 33141203806 is the correct part number for the clutch discs and that 33141203804 is the correct part number for 2.0mm thick dog ear plates. Having the original BMW part number makes the clutch disc refresh much cheaper than the Bimmerdiffs kit. There was a switch in parts in 09/1978, so that is probably when BMW went from 21T to 23T.

Hey MINIz where do you plan to get the cheaper clutch and dog ear replacement parts? Is it from Ireland Eng'g? How much cheaper?
Thanks.

The part numbers I listed are just BMW part numbers. You can get these from any BMW dealer or online retailers such as ECS Tuning.

I just sent another email to Ireland Engineering about the tooth count on the clutch discs. They did backtrack a little on being definitive on tooth count for the clutch discs and told me to email another company that has more experience. So, I think my previous post may have a premature conclusion on the clutch disc part number.

The dog ear plates should be the right part number. They are the same for all 168mm differentials. No tooth count difference or anything on them.

I'll report back on an answer to the clutch discs soon.