Differential Build Tool Ideas - Page 2 - PeachParts Mercedes-Benz Forum

97 SL320 · #16 12-19-2018, 09:08 AM

Quote:

Originally Posted by Roncallo

MB says these shims must be hardened. There are plenty of places that will custom make these but small quantities makes it difficult.
. . . . . . .
How about the side cap shims, same problem?

Yes, pinion shims need to be hard otherwise the front bearing will beat out the shim.

I'd be looking at other brands for shims ( Chrysler , Ford , GM ). Look at trade number on a MB bearing / ID measurement. Cross this to other brands and go from there. Even if the shims ID is smaller, a bit if work with a grinder will take care of that. Be sure to take into account the fillet radius on the pinion, we don't want the shim to interfere and hold the bearing up.

There are lots of rear end parts sellers online so searching will be easy. You can also look in a BCA / Federal Mogul or other bearing makers application catalog for non MB bearing numbers.

A last ditch effort would be to look in a machine shop / tool and die supply catalog. Sometimes they have shims but check to see if they are hardened.

Frank Reiner · #17 12-19-2018, 10:56 PM

Quote:

Originally Posted by 97 SL320

Yes, pinion shims need to be hard otherwise the front bearing will beat out the shim.

If the diff is in the rear, the shim will be associated with the rear pinion bearing.

Quote:

Even if the shims ID is smaller, a bit if work with a grinder will take care of that. Be sure to take into account the fillet radius on the pinion, we don't want the shim to interfere and hold the bearing up.

In MB diffs of the type Roncallo is working on, the shim is between the bearing cup and the housing, rather than on the pinion shaft.

Roncallo · #18 12-20-2018, 11:13 PM

For my build, I'm only replacing the pinion bearing and initial tear down inspection has shown the current pinion depth is perfect so I shouldn't need any shims. But I have priced out the shims and they appear to be under $13 USD each. But I haven't tried to order any so I don't know which ones will come back as no longer available.

I have requested price and availability for one of the online dealers. Hears the parts list with sizes.

size mm Pinion Shims
1.55 A 116 353 20 52
1.60 A 116 353 21 52
1.65 A 116 353 22 52
1.70 A 116 353 23 52
1.75 A 116 353 24 52
1.80 A 116 353 25 52
1.85 A 116 353 26 52
1.90 A 116 353 27 52
1.95 A 116 353 28 52
2.00 A 116 353 30 52
2.10 A 116 353 31 52
2.15 A 116 353 32 52
2.20 A 116 353 33 52
2.25 A 116 353 34 52
2.30 A 116 353 35 52
2.35 A 116 353 36 52
2.40 A 116 353 37 52

Stretch · #19 12-21-2018, 05:46 AM

If for example you were planning to fix up lots of differentials and you wanted a stock of shims so you didn't have to wait ages for delivery times then 10 to 13 USD per shim would mount up pretty quickly considering they are just a flat bits of metal

Have you considered the small differential cogs within the cage? Or perhaps with ASR it is different? (I dunno - I've only ever played with open differentials) - those shims are also expensive and those parts do wear

Roncallo · #20 12-21-2018, 07:23 AM

Quote:

Originally Posted by Stretch

If for example you were planning to fix up lots of differentials and you wanted a stock of shims so you didn't have to wait ages for delivery times then 10 to 13 USD per shim would mount up pretty quickly considering they are just a flat bits of metal

Have you considered the small differential cogs within the cage? Or perhaps with ASR it is different? (I dunno - I've only ever played with open differentials) - those shims are also expensive and those parts do wear

There is no doubt these would be expensive to stock. But these shim have increments of 0.05mm. That means that they have a tolerance of 0.01 or 0.02 at most. They are not just flat bits of metal.

My guess is any one doing this for a living will own a surface grinder.

Stretch · #21 12-21-2018, 09:05 AM

Quote:

Originally Posted by Roncallo

There is no doubt these would be expensive to stock. But these shim have increments of 0.05mm. That means that they have a tolerance of 0.01 or 0.02 at most. They are not just flat bits of metal.

My guess is any one doing this for a living will own a surface grinder.

Well horse for courses - but compared with say a ball bearing - a shim is from my perspective just a bit of metal - I argue ball bearings are much better value for money!

(As for the tolerance you quote:- "I wish" - most of the new shims I've bought from Mercedes don't have that kind of tolerance across their surfaces let alone the thickness they are meant to be)

######

I've been considering investing in sheets of shim material if only I could find a economical way of cutting them out.

Roncallo · #22 12-25-2018, 03:43 PM

Just received more tools to press the bearing races in. The smaller kit is available on Amazon for about $25 while the larger kit is ~ $100.

The smaller kit will take care of both pinion bearing except I will need to turn one of the adapters down a bit to get it to fit the smaller pinion bearing or just make a new one.

The larger kit will handle the side cover bearings but at $100 may be a bit over kill if your doing this job just once. You should be able to press those in carefully with a flat plate and then drive the down the final few thousands of an inch with a piece of 3.5" diameter pipe under a flat plate.

Both kits will handle the large pinion bearing but the larger kit comes with an extension handle to get down in the box.

97 SL320 · #23 12-25-2018, 07:38 PM

Quote:

Originally Posted by Stretch

Well horse for courses - but compared with say a ball bearing - a shim is from my perspective just a bit of metal - I argue ball bearings are much better value for money!

Ball and roller bearings are made and sold by the millions. Shims are a much slower mover.

Dana ( 30 / 35 / 44 / 60 ) liked to use shims under pinion bearing races so I'd have a look there.

Quote:

Originally Posted by Stretch

I've been considering investing in sheets of shim material if only I could find a economical way of cutting them out.

Run them on a laser table.

Roncallo · #24 12-26-2018, 12:18 AM

Quote:

Originally Posted by 97 SL320

Ball and roller bearings are made and sold by the millions. Shims are a much slower mover.

Dana ( 30 / 35 / 44 / 60 ) liked to use shims under pinion bearing races so I'd have a look there.

Run them on a laser table.

I just pulled mine out. It measured at 1.90mm. So I'm going to order 1.85, 1.9 and 1.95 before I begin. At least two of them I wont be using.

Roncallo · #25 12-26-2018, 12:28 AM

Pinion bearing pull tool.

I made a disk with flat sides to pull the larger pinion bearing. The disk needs to be 68mm in diameter and the sides cut off to make ~ 30mm wide piece. 1/8" thick broke on me so the one shown is 3/8" thick. Worked very well.

rwd4evr · #26 12-26-2018, 03:07 AM

Sorry this is slightly off topic but have you mesured to see the difference in a 2.47 LSD carrier and a 3.08 open or even 3.46 or 3.69 big gear carrier? I'm assuming the different LSD carriers are the same but machined to sit in the case different east and west. I can get low numerical fairly easy but a hign number carrier is unobtainium. I have one 3.23 LSD you'd have to kill me for. It would be great to be able to get a bit taken off one side and shim the other to adapt.

Roncallo · #27 12-26-2018, 12:00 PM

Interesting video not MB but the techniques still apply. Take a look at how he adjust his shims.

https://youtu.be/npUBF9Wj1Iw

Roncallo · #28 12-26-2018, 12:07 PM

Quote:

Originally Posted by rwd4evr

Sorry this is slightly off topic but have you mesured to see the difference in a 2.47 LSD carrier and a 3.08 open or even 3.46 or 3.69 big gear carrier? I'm assuming the different LSD carriers are the same but machined to sit in the case different east and west. I can get low numerical fairly easy but a hign number carrier is unobtainium. I have one 3.23 LSD you'd have to kill me for. It would be great to be able to get a bit taken off one side and shim the other to adapt.

I haven't but I know that the 2.47 and 2.65 carriers have a 6mm difference. Your not going to shim that out short of putting a 6mm spacer between the ring and carrier. Also if you do that you loose the ring gear pilot area and for the life of me I cannot find longer bolts required. They are an ultra fine thread that I just cant find. I would guess the larger carriers and probably a 12mm difference. Does Quaif or Wavetech make a suitable carrier for these gears?

rwd4evr · #29 12-26-2018, 04:40 PM

I think I remember tj wagamuth or somebody writing about having one done for his autocross car but I'm sure it was pretty pricey. Considering I get my parts free by reselling the rest of the car I'm not dropping a couple Grand. I can live with a welded diff if I gotta. I've got two 2.47 and a 2.27 sitting here though.

Roncallo · #30 12-26-2018, 06:14 PM

Pinion flange holding tool. Cut the circles out with a plasma torch and drilled the holes on a mill with a rotary table. Left it kind of long for the moment as its a lot easier to shorten than to lengthen.