I just finished installing a stock rebuilt 4L60 from a shop to replace mine that dropped dead at the end of November. I babied the truck around for maybe 10 tonight after I got it all installed to get everything opened up and flowing after sitting it at an idle for 20 minutes and shifting through all the gears a couple dozen times.

Here is my problem. When I start accelerating with the truck shifted in drive but resting at low idle it seems to pause (but still moves just a little) for a fraction of a second before catching kinda hard into drive (reverse does something similar). I'm also dealing with an odd shift between 2&3. Under heavier accel it seems to rev just slightly as it shifts between gears. None of the shifts are very firm in between any of the gears either.

Is this common with new transmissions or do I need to get it back to the shop before my warranty expires?

 

Sounds like it is low on fluid. Hope you didn't hurt your new transmission.

 

No this is not common in any way. As mentioned above check your fluid level also make sure that you have good connections at your electrical connections. If all this is good call the shop asap and do not drive until they say what they would like to do.

 

Fluid was plenty full.12 quarts total and right in the line. Called the guy and he said put another quart in. Did and still having the problems. He also said check the filter and make sure it didn't crack from pressure put on it by the jack.

 

Did you cave the pan in? If not I'm going to doubt it. But I guess you could check it out before you pull it and bring it back to him.

 

He told me to check just in case it did a bit and cracked the filter neck. I'll check here this weekend.