Lurching or jerking feeling at 55-70mph?

[McFizzl]

Just found your post, having the same issue. 1996 350 vortec, all new delco plugs, wire, cap, rotor, intake (upper and lower) gaskets injectors and new gm trans installed by dealer. Truck has a 6in lift and a bit of driveline wind up on acceleration. same range as you described. Will only happen while keeping steady highway speeds even worse on a slight downgraded road. Did you ever figure yours out??? Thanks!

Still haven't figured it out. I also have bubbles on my transmission fluid dipstick so might be a bad torque converter. The misfire code has stayed away but problem persists. so im thinking fuel pump cutting out of a transmission issue.

 

[Justjoshiny]

Ive seen something like this before, but I don't know what motor it was for. The oil pump was bad so it was shutting the engine down and then would start it back up constantly while going down the highway. Whoever it was, and I don't know what engine or vehicle it was on, but they went through 3 transmissions before solving the problem. I don't know if a bad oil pump would cause the engine to shut down and then restart, but its a thought.

 

[great white]

Ahem: Fault codes?

 

[twodrhoe]

Checked mine out with scan tool and monitored the torque converter and all was working as should. The tc was my first thought, checked codes and had a random missfire, and some o2 codes. Found that my jerking/surging would get worse when I pulled it down into 3rd so after checking my miss fire data while driving I noticed the engine was missing all around when the jerking would happen. I just happened to stumble across a guy that said his did this after a intake job (just like me) and he had to adjust his distributor. So after some some tweaking on it shes running great! Ended up turning it 1/4 in to the right oh where it was and all good for now!

 

[great white]

Checked mine out with scan tool and monitored the torque converter and all was working as should. The tc was my first thought, checked codes and had a random missfire, and some o2 codes. Found that my jerking/surging would get worse when I pulled it down into 3rd so after checking my miss fire data while driving I noticed the engine was missing all around when the jerking would happen. I just happened to stumble across a guy that said his did this after a intake job (just like me) and he had to adjust his distributor. So after some some tweaking on it shes running great! Ended up turning it 1/4 in to the right oh where it was and all good for now!

Question was directed to the OP, but nice to hear your problem is sorted.....

 

[McFizzl]

I had an intake job done recently as well. But my mechanic swears its not out of time. I get a random misfire code but only under WOT. Im getting a gas saver this week so the truck is gonna get parked and may just get sold off for a newer model or something smaller.

 

[qukon 95]

i had stumbles i used accel 8mm wires 4 months ago then it came back 3 weeks ago the wires was acking so took them back and got 8.5 mm accel
100.00 wire set so far so good.