Picked up my car with the new PI TC installed and the rest of the tranny completely rebuilt. Shifts are a lot smoother now and the effects of the TC are clearly noticeable.

However, the next morning, there were very noticeable vibrations when slowly accellerating in 1st and rear, up to approx. 1200rpm. Also, it feels like the parking brake was engaged.
Above approx. 1200rpm and in gears 2 and higher, everything appears to be fine. Also, after about 1/2 hour of driving, the vibrations are gone.

Any ideas what this could be?

 

Wild guess without talking about anything technical of the transmission I don't know..

Transmission mount?

My tranny vibrated a lot before I changed the mount. But then again I'm stock as far as drivetrain goes.

 

supercoupes,
who rebuilt your tranny? bring it back to them for warrantee repair. Is it a SC4 ? Did they put in Type IV?

 

If that's the case, wouldn't the vibrations be present in any gear at aroung 1000 - 1200 rpm, not just 1st and rear?

It's a SC4, and I took it to the most reputable tranny shop in my country. However, although I pointed out the importance of type IV, they actually used Esso (Exxon?) LT71141. Could that be it?

It the vibrations don't disappear within the next days, I'm definitely going to take it back to the shop. I'm only hesitating because it's 300miles away.

Thanks,

 

the SC4 tranny needs T-IV stuff is wicked expensive (unless you work at the dealership!) and it's one of a kind... some companies sell T-IV mimicking additives... junk.

it's kinda like a washboard/rumblestrip vibration, right?

I had that when my tranny fluid was goo -- it was dark black... I showed it off at the CL meet I had a year ago. the SC4 needs new fluid every 15k. No two ways about it.