I recently replaced the midshaft/carrier bearing and rear universal on my 98 C1500 automatic with about 175K. Since then, twice I have had a really violent shudder taking off in reverse. Moving from P to R, reverse feels like it engages properly, then when throttle is initially applied, there is a massive shudder until the throttle is released, when it immediately stops. The wheels don't seem to be turning during the shudder. After the shudder stops, the truck moves normally with gentle throttle. I also experienced a similar shudder once while moving; probably in 2nd, accelerating fairly gently up a hill. Same deal; foot off the gas and it stops. My usual mechanic was able to reproduce the shudder in reverse once (it was parked downhill), but then wasn't able to do it again. He figures it's the transmission, which seems about right to me too (it's original), but I figured I'd see if anyone had any ideas before I go to the transmission shop?

I don't see how it could be directly related to the work they did, since all they did was pull the driveshaft off to replace the bearing and ujoint. The shudder is violent enough that I can't really pinpoint where its coming from. I've been babying it around town for a couple of days since and haven't had it happen again.

 

Crawl under the truck and see if the bolts are in place that hold the carrier bearing.

Allan