Tranny shudder

Catsup said:

I've got '97 GT that's still stock except for K&N air cleaner and flowmasters (yeah I know but you gotta start somewhere!).
I've got a bad case of the shudders between 2 & 3rd unless I'm under heavy acceleration. Any ideas what would cause that?

Click to expand...

This is a common problem with early 4R70W's. There's actually a Ford TSB on it (98-8-7). The problem is heat. When excessive heat is present, it creates a breakdown of the oil/friction material interface. The cure calls for the addition of an external transmission cooler to keep fluid temperatures down and the switch to the improved Mercron V transmission fluid.

This would be a good time for a torque converter flush and the addition of a new transmission filter while you're at it.