Buzz

I have a F150 V8 with automatic trans. Every now and then it will slip when shifting. Always at 25 MPH. I cant make it do it, but it seems to happen when taking off slowly on level or slight decline.
I have had it to the garage and they reprogramed the computer, but it still happens.
Any suggestions?
Thanks

Kattumaram

Four items in the system can affect tran operation:
MAF (Mass Airflow sensor)
TPS (Throttle Position Sensor)
IAT (Intake Air Temp sensor)
EPC (Electronic Pressure Controller solenoid, inside tran.)
All of these items affect line pressure in the transmission which, in turn, affects
the quality of the shifts.

It seems to me that the truck is too new to develop major problems, but anything is possible.

I'd suggest cleaning the MAF elements as a start, then procede to check the IAT sensor for correct resistance vs temp, then possiblly replace the TPS. The EPC will need attention by a competent tran shop, if you can find one.

Buzz

Thanks Kattumaram

I will bring this up with the dealer.
I only have 10000 miles on the truck, the first time I noticed it was at 200 miles. I am making them document the problem every time it happens so if there is a malor problem later it will be taken care of.
I dont know if I discribed the problem accuratly.
when it does it ,the engine revs and it slides into the next gear. Does that make a difference?
Thanks again
Buzz

texasedition

I would not touch it. Just take it to the dealer and let them handle it. Dealerships are getting **** with warranty now, well at least my local dealer. If it keeps happening after you pick it up, make sure you keep taking it bad, so you can build a history with this problem in case your truck ends up needing a tranny at like 60001 miles.

SHERRI_001_001

Hi all, I am having similar problems with slipping, but just yesterday I was in reverse and then put it in drive and it would not move at all, it was like it was in neutral. So I put it in 2nd and then back in drive and it worked. Do you think my tranny needs to be replaced or just re-programmed?

mustangGT90210

Sounds like some slop in the shifter linkage ^^

BJV269SS

Get yourself an Edge Evo. Punch the trans # up to about 20. You'll be amazed at how nice the trans will shift after that. Nice and firm.

brinker232

I have a 2008 F150 XLT with a 4.6 and auto tranny. At 25,000 mi. the "Front Pump and Torque Converter" went out. Bayway Lincoln in Houston did the repair as they are the "Advanced Ford Transmission Shop" in Houston. (Hahahahahahahaha) Sorry! Now I have 13,800 on the tranny since the repair and its slipping and hesitating again. The dealer response is "Sorry, your Warranty Has Expired." I went to change the fluid and filter myself over the weekend and found that the dealer had "stripped" 4 of the 14 pan bolt holes and "rigged" them back together! I ended up having to heli-coil the 4 holes. Sounds like these trannys are crap! I am afraid of having to replace it with only 29,000 miles on the truck! And no, I don't pull anything bigger than a Jon Boat! If anyone has any suggestions or ideas, please help!

TCBJR23

Dug up this old thread, my truck is doing the exact same thing. Been to the dealer twice and they tell me there is no issue. At 25 mph it slams into gear, always on an incline like its having trouble selecting a gear. Was wondering if you were able to get your dealership to fix it?

Buzz

I finally fot mine to where I could make it slip. Slowly, not to slow, bring it up to 23 -24 mph back off a little then give it some gas. I got to where I could do it every time.
After I could make it do it I took it to a dealer in Perscott, AZ. They replaced a couple of bad valves and a servo. Hasn't slipped in 30,000 miles.
Hope this helped.
Buzz