I've got a '98 f-150 4x4 with the 4.6L in it. Over the past couple of weeks, when the tranny shifts between 35-40mph under normal acceleration, it was shifting kind of rough. Like a minature shudder, then it went into gear. Last night while driving, when it first shuddered, I kept the throttle steady at the same speed and it kept shuddering and the rpm's kept varying a little. It's like it wouldn't shift into gear or something. The tranny fluid is FULL and is not burnt. Any advice????
The truck has 86,000 on it. Not sure if the tranny has ever been serviced or not. I bought it when it had 62,000 on it. Has probably never been changed. I may try this, but the fluid did look really good.
There is probably a 1 in 100 chance the previous owner did any maintanance to it - especially transmission flush. If you want to fix your problem, I guarantee you that'll do it if you do the whole procedure.