I have a 1999 24v auto and I am coming to my Wit's end...I have changed batteries, alternator put in a tps noise silencer, cleaned my grounds, moved my ground away from the alternator, added a extra ground also a tps sensor and my truck seems to still be hunting for 4th get over drive. I can't calibrate my tps either bc the signal wire is 100,% always saying I have 4v like it thinks I'm full throttle all the time...someone help before I blow this thing up.

 

Well- your truck is fine except for "hunting" TC lock on and off?

Or is it really shifting 3-4?

Maybe you could install a lockup switch to test what your problem really is.

 

So I changed the transmission fluid and filter...the filter was black..... Guess the guy become me only replaced the fluid...she seems to be shifting now but the rpms are still high....like 60mph grabs 2,200

 

Maybe use Amsoil Engine and transmission flush, then drain the entire transmission (including TC) and fill again. It sounds like it could use it.