When I'm driving with the transmission in fourth gear or overdrive, and come to a hill steep enough to make the truck shift down, it works as it should. BUT, when I make it up the hill and the transmission shifts back into 4th or overdrive, most of the time, the truck starts to "shiver" or "shimmy". It'll only quit if I let completely up on the throttle for a ways. From then on it'll drive fine until I come to another hill (lots of hills here):o

A couple times after this situation, when I did not let up on the throttle, the engine started "bogging down", and actually died on me. Not fun!!

My truck has about 125K miles on it and had been used to pull a 5th wheel rv for most of its life before I got it.

Anybody have any idea as to what's going on here?

I'd sure appreciate any help!

I would start out simple and check tranny fluid level. Also could be a problem with how the tourque converter is locking up. It is controlled by a solenoid in the transmision valve body and it is controlled by the computer. You might take it to a trans shop an ask some advice. If it was the engine, I think it would down shift to make up for the low power output.

Thanks bwood, yeah I don't think it's the engine either. Probably need to take it to a shop. I've already done some reading, and I may have a more serious, but common GM problem with my transmission. It's a 4L60E, and even if I undertake to tear into it myself, by the time I buy the specialty tools that I may end up needing, I'd be at the price of a reman. tranny, so...we'll see.

Probably be wise to get an expert to do this one.:(

Thanks again

I might be wrong but the shift solenoids and torque converter lockup solenoid are accessible through the trans pan. They are bolted to the bottom of the vavle body. They are available through most parts stores.

My '92 Bravada started doing that 4 years ago coming home up I-81 from PA. Put it up on the hoist and disconnected the plug to the torque convertor and haven't looked back. We have put a ton of miles on it since then, and even pulled the trailer half a dozen times.

I had a problem similar to this in my 99 Suburban. When going up a hill the engine would bog down and start backfiring although it didn't do it exactly the same every time. Sometimes it would barely make it up a hill. It turned out that it was the FUEL FILTER. Its a cheap fix and might be related.