this thing is brand new,bolted to a 385 .at hiway speeds [2100 rpm] about every 20 miles the tac drops about 400 rpm [1800 rpm],runs like that about 20 miles then back up to 2100 .while its in this phantom 5th gear i cant kick it down into 4th i have to gear down to 3rd then into 4th[od] i ve been told its the shifter cable [my mechanic is losing his 5 star status ] opinions thanks
