Whenever you let off the accelerator the truck will buck. Won't do it if I coast in neutral. As long as its in gear at any speed

88 4.9 m5od

 

The problem may be in the transmission.

 

If the clutch is slipping or you have hot spots, the engine and transmission won't be decelerating at the same speed causing a jerking motion.

 

Well that isn't exactly what I wanted to hear but thanks guys

How can I troubleshoot this? To see if the clutch is slipping or if I have hot spots? Or anything else it may be?

 

Does the truck start to shudder from a dead stop? Can you get the truck going in third gear? Those are early indications a clutch is begging to slip. You would have to inspect the flywheel for hot spots.

 

It will shudder from a dead stop. And ill have to check on the starting in 3rd. Ive never changed a clutch before, is it something that can be done over a weekend at home?

 

It'll start off in third if I give it enough gas. Not good

 

It can be done over the weekend, the difficult part is dropping the transmission out of the way. It helps if you have an extra pair of hands to help you and a floor jack to maneuver it. You need to pull the driveshaft but drain out some if the tranny fluid or get a transmission stop. Its a rubber plug that keeps the fluid from pouring out. Remember to set the parking brake or chock the wheels to keep it from rolling away.

Remove the shifter boot and fold it backwards to get to the shifter bolt. back off the nut and put it on the threads on the opposite side to pull the bolt out. Disconnect the clutch line, the reverse light switch, unhook the battery before removing the starter then undo the bolt for the cross member.

Only do the 6 bolts at the bottom and don't worry about the ones on the side of the frame cause they are nearly impossible to reach. Then lift up the transmission and knock out the cross member sideways. Get to the approx center of gravity of the transmission and unbolt the remaining 5 bolts that hold the transmission in place and the 2 small cover bolts on the front of the transmission. Start pulling the transmission backwards, it may take a few tries but it should simply slide out if you have the transmission at the correct height to balance it and come out.

Now you have full access to the pressure plate, clutch and clutch slave. Its a good idea to replace this too so you don't have to remove the transmission again in the near future. When installing a new clutch its a good idea to either have the flywheel re-surfaced or buy a new one. If its has blue discoloration on the face, that means its a hot spot and you will have to replace it. Then reverse procedure to install and you're all done.

It takes me under and hour on my own to drop my transmission out.

 

If you have a hard time backing the trans out put the hose back on the slave and push the peddle in.

 

This truck is also 4x4. Will this add difficulty?