Hesitating C1500 Only at Highway Speeds and Under Load

[Gatorboy]

Hey guys I'm new to this forum, but not to chevy pickups. I do need some help though. I have a 1995 GMC C1500 with the TBI 350 and 4L60-E transmission. During highway speeds (40 mph and up) the truck jerks almost as if it is jerking like a bucking bronco. During this there is NO noticable loss in RPM or oil pressure. Only happens when I'm lightly getting on the gas to go up hill (between 1300-1500 RPM) or to pass someone. Goes away if I hammer on the gas and get above 1500 RPM. Anyone have any ideas? Any help is appreciated

 

[92GMC]

i had a truck that done this exact same thing. never figured it out and it drove me crazy. i think it was something in the transmission

 

[Gatorboy]

I was told it could possibly be the TCC solenoid. I'm going to upload a video tomorrow to hopefully help you all help me lol

 

[Kyle97GMC]

Mine was doing something similar to that and I took off the throttle body and cleaned it up. I then ran sea foam through the engine and havent had a problem since. Dont know if it will help your situation but it might be worth a try!

 

[TruckinAin4Sissies]

By how many RPM's is it jumping?

A good way to test TCC-Lockup is to bring it up to 55+ MPH and hold your (right) foot on the throttle (no cruise control).
With your (Left) foot slightly depress the foot brake and watch your RPM's, it should jump ~200 RPM.



-Truckin-

 

[Gatorboy]

By how many RPM's is it jumping?

A good way to test TCC-Lockup is to bring it up to 55+ MPH and hold your (right) foot on the throttle (no cruise control).
With your (Left) foot slightly depress the foot brake and watch your RPM's, it should jump ~200 RPM.



-Truckin-

It really doesn't seem to jump or move in RPMs at all but I'll check again tomorrow when I get it out on the highway

 

[rccoco]

Im having the same problem with my truck. Ive had it for awhile now.

 

[Gatorboy]

Well looks like I'm not the only guy that would love a solution! Does yours move in RPMs?

 

[rccoco]

No i don't see a change in the Rpms, it just sorta jerks around and feels like its falling on itself haha. But when i give it a little more gas then it goes away.

 

[Gatorboy]

Yea sounds about the same. I would love to figure this out, it's annoying and a waste of gas to keep hammering on it to make it go away lol