The Stovebolt Site Forums The Shop Area Engine Shop 5th gear in a 700r4

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

it might be the Throttle Valve cable, which what controls the downshifts. Try readjusting it. There may also be an issue with the torque converter lockup. At highway speeds, it should remain in lockup, not go in and out.

so if it dosnt stay in lockup is that a warranty issue

Disconnect the electrical plug on the left side of the trans. & drive it. If it works without it hooked up then it is a problem with the lockup. You may not want to mention to the trans. place that you did this. It won't hurt anything but he could use it for a way out. My trans shop says you don't have to run a lockup if you don't want to but it's better to have one. There are several ways of controling lockup. Different kits & different shops use different systems. If it is a lockup problem it could be the controls or inside the trans.