so heres my very weird problem...my max is a 02 with a 6spd tranny...i can shift threw all the gears fine..no probs...but only 4th gear vibrates when in that gear..cruise or going fast...it only vibrates when you let off the gas...the faster you go the more it wll vibrate when de-accelerating..its kinda hard to explain...2nd gear...or 6th gear dont vibrate for nothing...just my 4th...i looked at everything and nothing is touching it or in the way...i cant figure it out...any ideas?

 

The only thing I can think of is motor mounts, maybe?

 

nope..i have the es inserts and it wuld happen with every gear with motor mounts shot...but it jus happens with 4th gear