every time i shift from 1st to 2nd and i get to 2000 rpm there is a small vibration that occurs for about two seconds until my rpm gets up a bit. It does it every time and i can't figure it out, any ideas?

 

Sure its rpm related does it do it a certain vehicle speeds? At idle reved to 2k rpm does the vibration occur? If not its drive line related. First thing i think of is U-joints. Get under truck and see if there is play in the rear drive shaft u-joints. There should be "none"

 

I should have been more clear, it does it at about 20mph which is usually at about 2000rpm. does not vibrate when sitting still at 2000rpm.

 

Check U-Joints a drive shaft. Lug nuts tight? Any noise involved?

 

no noise, just the vibration. could the clutch have anything to do with it?

 

also, it's very smooth all other times.

 

Does it vibrate as you let off the clutch... At highway speeds is there and jerking or feel its missing?

 

Make sure your yokes are bolted down tight...

 

Yea driveshaft bolts for tightness...