i have posted this on dieselstop and got no replys... its short and sweet when i come to a stop and go to accelerate its almost like it hops for the first 10 15 feet then it stops. first started to happen on sharp turns now its happen when i accel from a stop... i was think its the rear diff fluid and the friction modifier

 

have u checked your fluid? what about checking ur u-joints?

 

i checked the fluid its good but you can tell its very old. the oil feels like its sediments. the sediments feel like sand but is prob metal shavings so im gunna change it when i get a chance and the u joint could get replaced but its not bad yet.

 

Is the truck lifted at all?

Any mods done to it?

 

its a early 1999 its got 450 springs in it, diamond eye 4in, tymar intake, 04 headlights, tranny,pyro,and boost gauges for now id say its got about a 2inch lift with the springs

 

Check the pinion angle. I cant remember if the short boxes have a one piece drive line or two piece, but check the center support if it has a two piece. If its a two piece thats more then likely the issue.

 

Mine is identical, it's a one piece shaft. I'd block the front tires, put the rear on stands, remove the diff cover, and place it in neutral. Inspect the gear while slowly turning the tires, look for pits, breaks, ect.

 

Check the slip yoke too.

If it's bound up it'll be loading and unloading the rear suspension.

If it ain't that I'd guess the carriage bearing like Joe said.