2000 GMC Savana - 4L60-E (M30) transmission

[FooFooTheSnoo]

Looking for some insight.

We've had this vehicle since bought new in 2000. It's a Debut Conversion (high top); 5.7L V8; 3.73 rear w/locking diff. It has about 125K miles. The last tranny service was done by dealer back at about 81,500. Just a flush/filter.

Yesterday I'm attempting to accelerate on the entrance ramp to the freeway (engine normal temp, only about 5 miles driven to this point) and the vehicle starts to buck like it’s starved for fuel – minimal forward movement. Not realizing what the problem is, I give it more gas and seemingly and eventually get’s up to freeway speed. I kicked the cruise on – no worries for appx 30 miles.

I now pull onto my street and the same situation, but this time I don’t give it more gas, I moved the gearshift lever in to 3, 2, 1 in succession. My momentum got me to the driveway. I don’t think shifting did anything.

After I was home in the driveway and I put it in reverse and similar situation, it seemed as if the engine was willing but the tranny wasn’t doing it’s job. Now I’m at the end of the driveway (slightly sloped toward street) and I put it in D to move back up the driveway. After a few seconds of flooring the accelerator, I was able to get it up the driveway.

Here’s the kicker… I’m going to be giving this to a dealer as part of the Cash for Clunkers program (days/week or two?), but my new car isn’t ready yet. We’ve filed all the paperwork for the rebate/voucher, but this happened after the fact. So I’m not really inclined to put much $ into it. The program states that the vehicle must be operational.

Any thoughts / insights would be greatly appreciated.