S50+G260 grinds when shifting

[bimmer630]

Anybody having trouble with clutch release on their swap with a g260 trans?
I have a new clutch and a resurfaced flywheel, I told the guy to maintain the step down on the outer edge of the FW too.
Its only in the morning during the first few minutes of driving, I grind sometimes if I shift too fast, then, the rest of the day, It shifts fine.
At first I was sure I had air in my clutch hydraulics, but I bled It out with a power bleeder twice, with the slave removed and the pushrod held in all the way, And its still the same.

Maybe a slightly longer pushrod is needed after machining the FW?
Or its just something as simple as a bad slave (??)

[DesertBMW]

Its only in the morning during the first few minutes of driving, I grind sometimes if I shift too fast, then, the rest of the day, It shifts fine

this is a symptom of worn synchronizers or you are using thicker than required oil.

[bimmer630]

Come to think of it, I am using a tranny that was in a trashed car... Threw it in there as a backup when I broke the mounting ear off my "normal" trans (This was all before the 24V swap)
Ive been meaning to get that other trans mount Tig welded back on and try it out

[bimmer630]

Why would this only happen in the morning, though

[LJ851]

Why would this only happen in the morning, though

Cold oil.

[e30austin]

Use Redline MTL or Redline 75w90. Change it and report back.

[Wanganstyle]

Why would this only happen in the morning, though

What oil is in this mystery transmission?


Does it have enough oil?

if the issue only happens when the box is cold; switch to a thinner oil; use ATF (automatic transmission oil).




a parallel issue I had with my e39; the Getrag 6 speed boxes are only designed for light thin ATF and using MTL 75-90 will cause the syncros to be extremely grumpy until the fluid is warm. Drained box and filled with wrong oil to cause own headache and then drain again to fill with proper oil.