Hello all, a few weeks ago I drained what fluid would run out with pan dropped and changed filter. I was having hard shift from 1st to 2nd. Didn’t matter if I accelerated slow or fast, shifted in Normal rpm range but hard. I put seafoam in trans and drive 50 miles or so before draining. After couple days of driving the shift problem improved dramatically, still an occasional hard shift. It shifts fine when shifting manually. So should I add another seafoam and drain it again and change filter? Thanks

 

Any update or comments on this?

 

I changed the Throttle position sensor and my transmission started shifting normal. I’ve been driving daily for several months and not one weird shift and changing that sensor. I had rough idle, weird rpm jumps when driving, and hard shifting. That $28 sensor fixed all of it lol. Someone here replied they didn’t think that sensor had anything to do with transmission shifting, but I can tell you it did on mine. Have a great day!

 

Three cheers for fixing yours.
Someone else just a couple of months ago posted the same symptoms (erratic hard shifting, odd idling) and fix (replacement TPS).

I'm wondering if we should clean and/or lube the TPS.
Is there an "average lifespan" for our TPSs?
Also, can the TPS be tested in a manner as simple as tapping it while at some rpm above idle?
Maybe hold the throttle open manually by pulling the cable then giggling the TPS to see if it changes rpm?

 

Several years ago, had the TPS fail; forced 5r55e Tranny into some sort of FailSafe mode & not shift above 2nd gear.
Had to drive highway home 20+ miles in 2ndGear & high RPMs; thought for sure Tranny had died.
Took several hours of figuring out what the TroubleCode meant & then measuring the TPS signal.
TPS is just a 3wire potentiometer\resistor; my factory original had burnt spots causing erratic signal.
Yep, 20minutes installing a new $25 TPS fixed the issue.

 

Not sure about testing or lubing, mine was loose when I bought truck. Screws were not correct and it wouldn’t tighten down. I put good fitting screws in it but always had the rpms jumping up and down while driving so bought one and waited a couple months before I put it on. I was looking at used transmissions for $1200-1600 range..one day decided to change tps sensor for rpm issue and was Pleasantly! Surprised when I realized it fixed my tranny issue. It was motorcraft brand and was $28 from advance. I was so happy to not be looking for a transmission lol!