BMW Compact Build

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john vanlandingham
Low traction and tight means it doesn't slip like say on low--45-60 ft/lbs and lots of grip..So on asphalt it differentiates more, and that mean slip and eventually wear. So gravel is LESS stressful to the plates.. I have had plate look marvvy for 10 years on my massively powerful Saab.

So if snow and ice don't cause it to slip because it doesn't exceed the breakaway torque...any thoughts on what I should be looking for when we tear it apart? Any sort of test I should do with it while its still on the car?

When I have both wheels off the ground they both spin the same direction. If I put one tire back in contact with the ground, I can't spin the other.

Quote
john vanlandingham
I have had plate look marvvy for 10 years on my massively powerful Saab.

Is that sorta like the saying "if a tree falls in the woods...."

Dave

Quote
DaveK

Quote
john vanlandingham
Low traction and tight means it doesn't slip like say on low--45-60 ft/lbs and lots of grip..So on asphalt it differentiates more, and that mean slip and eventually wear. So gravel is LESS stressful to the plates.. I have had plate look marvvy for 10 years on my massively powerful Saab.

So if snow and ice don't cause it to slip because it doesn't exceed the breakaway torque...any thoughts on what I should be looking for when we tear it apart? Any sort of test I should do with it while its still on the car?

When I have both wheels off the ground they both spin the same direction. If I put one tire back in contact with the ground, I can't spin the other.

Quote
john vanlandingham
I have had plate look marvvy for 10 years on my massively powerful Saab.

Is that sorta like the saying "if a tree falls in the woods...."

Dave

huh?

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Quote
john vanlandingham
Is that sorta like the saying "if a tree falls in the woods...."

huh?[/quote]

If a rally car with an LSD sits in a garage the diff can't wear out, right?

Did we ever check breakaway torque on the diff after reassembly.
Quick disappearance of locking ability might not be too unexpected, my guess is it will be super apparent once the diff is disassembled.
How did you choose which shim to use? Did the shim go under the Belleville?
I'm going to guess it's something failing completely. Could be a soft Belleville, loss of all friction material on plate, etc.

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Grant Hughes

Quote
NoCoast
Did we ever check breakaway torque on the diff after reassembly.

No, I don't think we did.

Quote
NoCoast
How did you choose which shim to use? Did the shim go under the Belleville?

The instructions came with a suggestion on which shim to start with, saying to use those, then test backlash. We did that and the backlash was at the spec they called for so I bolted it back together.

Dave

I'm confused. The small shims that go with the Weir kit look like they are adjusting the Belleville and should have any effect on backlash. The backlash adjusting shims are the large diameter shims on the bearing carrier for the stub shafts. The shims that come with the Weir kit are small and went internal to the diff yeah?

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Grant Hughes

Quote
NoCoast
I'm confused. The small shims that go with the Weir kit look like they are adjusting the Belleville and should have any effect on backlash. The backlash adjusting shims are the large diameter shims on the bearing carrier for the stub shafts. The shims that come with the Weir kit are small and went internal to the diff yeah?

Entirely possible I'm getting my terms mixed up. I think there's a direction sheet with the kit you have. I thought the shims were used to make sure the width of the assembly was the correct width after removing the stock spring/washer and replacing with the belleville washer.

Dave

Grant, those shims he is referencing are to set the backlash of the spider gears, as they go between the spider gear cup and the LSD housing, which will also set preload on the clutch pack.

When I did mine, is was super agressive at first, then softened up with driving.

Ah gotcha.
Few easy solutions...

http://www.nengun.com/search/#t:n:u;m:83;c:77;d:1;g:1

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Grant Hughes

Quote
NoCoast
Ah gotcha.
Few easy solutions...

http://www.nengun.com/search/#t:n:u;m:83;c:77;d:1;g:1

Thanks but no thanks. When I built the Evo I tried going with Cusco crap and blew it all up within a few hundred miles. Now running stock plated rear (with more plates) and a Wavetrac and both have been much more reliable not to mention cheaper.

With the BMW's more budget focus, I'm thinking either get some new friction plates and try the Weir kit again, go with the Weir full lock kit ($180), or pick up a spool ($100-175).

Since the ring and pinion seem to be adjusted properly in the 4.3, I'm thinking going with the Weir solid or spool are similar options, just not sure if one would require re-doing the ring and pinion backlash. I know the weir would not, but unsure how the spool install would go.

Dave

If you look at the last one on that page, the TRD adjustable one, it looks like it simply shims the Belleville to adjust the amount of lock up.
How much are new plates? I'd wait til disassembled and find out what's going on. If all looks good, I'd say new plates, check breakaway torque, shim Belleville until get desired breakaway.

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Grant Hughes

Quote
NoCoast
If you look at the last one on that page, the TRD adjustable one, it looks like it simply shims the Belleville to adjust the amount of lock up.
How much are new plates? I'd wait til disassembled and find out what's going on. If all looks good, I'd say new plates, check breakaway torque, shim Belleville until get desired breakaway.

so close. open it up and look, then measure thickness.
measure.

You're too wasteful.

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Jig dilemma for the new JVAB 50mm inverted struts solved.

Now what's Dave's number?

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Quote
john vanlandingham
Now what's Dave's number?

This week it's 12.42 under 10.

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Grant Hughes

Quote
NoCoast

Quote
john vanlandingham
Now what's Dave's number?

This week it's 12.42 under 10.

Wha?

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.