So this has happened twice, both times I'd say around 40-50mph. I had the transmission in OD, and all was smooth until bam! a good buck/shake/jerk happened and lasted maybe 1 second or so. Engine volume seemed to increase as well. Both times I let go the gas pedal and it seemed to go back to normal. It actually scared my wife 2nd time it happened lol.
Any guesses what it might be? Since the 2nd time, I've only been driving in D (not OD) as I was thinking maybe the OD gear in the transmission might be the culprit?
Thanks!
Scott
ps. if you're ever in Honolulu come by I'll show you the car!
Sure sounds like a transmission problem to me now if it happens often enough do my video finding the source of car noises Scotty. If you have a sensor on a transmission when it jerks you hear the noise coming from the transmission then you know that's what it is
@scottykilmer answering this way late but actually it was sometimes misfiring I think (sorry I'm not great trying to describe a noise I guess lol). after having it happen a few more times i noticed it happened when it rained. i ended up replacing all the spark plugs and wires myself and it's been running fine since. the plugs looked good (no carbon buildup) but i did notice their gaps were way off (some too big, some actually too small for the car's specs).
This sounds like the famous GM bad torque converter shudder.
Is the "famous shudder" you mention the same thing as the TCC locking up due to a failing solenoid? I've come across this TCC solenoid issue as I've been perusing other websites...
Nope, failing torque converter. Same thing happened to my '84 Blazer.