I have been having a strange issue ever since buying my truck in december. It feels like the truck jerks when I get on or off the throttle quickly. I really have to feather the throttle to have a smooth drive. At first it seemed like a motor mount, same symptoms I had with my toyota, but I checked under the hood and didn't see any excessive movement from the motor while revving it. I'm wondering what to check next? Too much lash in the diff? worn gears in the trans?

 

Check u-joints while your at it. Have someone help so you can look at the joints while they load it up a little in gear. Try going from drive to reverse and back while keeping the rpm a little over idle.

 

the truck's a 5spd if that help?

 

What year of truck??Is it the drive train jerking or is it the engine surging?

 

Truck is a 97, feels more like drive train jerking, as there is a slight delay after the engine RPM drops or raises

 

Most common cause of jerking from a sensitive throttle is a broken or unhooked throttle return spring(s).
There are two springs, one inside the other that stretch inbetween the linkage and power steering pump.
You can replace with hardware or autoparts store springs for less than five bucks.

Also read this http://dodgeram.info/tsb/1997/18-29-97.htm
The kit in this TSB is over $100 and is basically just stronger springs with a bunch of other parts you don't really need.

Also check that the two small bolts on the rear lever in fig 1 in the above link are tight.

 

It's not really a issue at steady or mild acceleration. That's really the only way I can keep the truck steady. Would the return spring affect both acceleration and deceleration?

 

Without strong return springs it's very hard to keep your foot steady on the pedal at any time with truck and road vibration fighting you.

 

If you get it both coming onto and off of the throttle, there is a good chance that it is from all the slack in your driveline. You can lie under the truck with it in gear and try to rotate the driveshaft and then do it again out of gear. If there isn't a lot of slack there, it is likely to be your throttle return spring.

 

Yes, If not return spring most deff. slack in the drive train. I had the this problem with a 97 3500 w/ 270K miles. Between the sloppy rear end and the sloppy 5 speed tranny you would almost have delay in the throttle responce LOL..... It bucked and jurked every time i touched the go pedal. I couldnt stand it i sold that pos.

 

My 97 3500 5 spd 4x4 bucked like crazy before I put the missing throttle spring back in. It had a piece of missing spring still hanging on the linkage. I got 2 new springs at dealer for $10 I think and it fixed my touchy throttle.

Mine had 2 springs parallel 2 each other with grey plasitic ends that popped onto the ball studs (under the fuel solenoid in that area). I had to use a mirror to see it since its hard to see under that area. I found one grey plastic end hanging on a ball stud joint and spring was missing. Throttle was very touchy and bucked alot. Throttle was too sensitive without all the springs.

 

in gear, I have no slop. Out of gear, I am getting maybe 1/2" of turn, I would say some slop. Guess I'm looking for the slop after the trans? I dont see any signs of worn u-joints, so work diff gears? am I able to re-set the lash of these things? it's got a dana 80.

 

1/2" of turn isn't actually all that bad with these trucks but it isn't good.

I would strongly discourage resetting the lash. Your gears are worn into how it is set and if you reset it, it will probably howl for longer than you can stand. I have a fair amount of slop in mine and have just learned how to drive with it. I had completely forgotten that I had that problem until this thread.

 

There is a recall for throttle linkage and it comes with new springs. Recall B-15