bucking minimal and lag like its trying to go... usually around mid range and low rpms.... will not happen if above 2500 rpm.... tried it out of over drive still does it... does anyone know what i could check or replace to fix problem replaced all coil packs about 10000 miles ago... it has spit out 2 plugs and both have been fixed with time certs... tranny has been rebuilt about 10000 miles ago... the rear end bearing is going out but couldnt see why it would shudder like it is when it is...

 

Any codes? How many miles on what brand plugs? What brand coils? Throw a bottle of Techron in the gas.