CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

F150 Transmission trouble

My F150 has had numerous transmission problems. It is on its second rebuilt transmission. About 6 months after this latest fix I was having problems with it yet again. The rpm’s were going thru the roof at about 30mph. When I took the overdrive off ( this would make it run smoothly prior to transmission repair ) the truck seemed like it didn’t want to go much faster than35mph. I had it towed to the shop that did the repair and was told that it was not the transmission but the throttle body actuator that needed to be replaced. I was quoted $1,100 for the repair, which I did not have so I instead had the car towed back to my home. When I called around I was told over and over again that this was quite a lot for this repair. I have had several issues with my truck after this transmission repair thou the mechanic rudely insists they have nothing to do with him. A couple of months ago I took my truck to a shop that I dealt with thru my work and was recommended by other employees. They told me that there was no way it was anything other than the transmission. The mechanic that fixed my transmission was supposed to go to the shop and take a look at it there so they could show him what they found. Now two months latter he says he has no time to do this and insists on having it towed to his shop instead. The transmission is still under warrantee with him. My problem is I don’t trust him at all anymore. I called the dealership where he claims he took my truck to get a diagnostic and they have no record of this. When I asked him for a copy of the diagnostic again he turned rude. Does anyone have any advice for me on what to do. Is this definitely the transmission?

I am having a hard time finding critical information on your F150. What year, engine size, transmission, mileage, etc is your truck.

Hope to help.

It is a 2004, V-8, 4x4, 5.4L, about 155,000 miles. It is a rebuilt Ford transmission.

if your truck has a dip stick make sure the tranny fluid is at the correct level. and get a second opion on whats is wrong with the truck. i would talkto other people how have about the same f-150 see if the have any insight with what is happen with your truck or know a honeswt shop that is good with fords.

Another question that may help us, now that I know the year. Has any Diagnostic Trouble Codes been pulled from the Power Control Module? If you have that or can get it, please pass it along. It/they can help us in discussion.

Your truck does have a throttle by wire system. The throttle pedal moves a couple of potentiometers to instruct the PCM what power demand is being requested. The throttle body motor adjusts the throttle plate to match the potentiometer setting desired by the PCM. If the PCM finds an error it will settle the throttle position into a “limp home” mode that will limit the speed to 30 mph. But if the PCM finds an error it will set a DTC and maybe turn on the MIL.

I asked the original repair shop to fax me a copy of his diagnostic and the one he claims he had done at the dealership. I have not received ether though.

He did say that it was causing the truck to go into a fail safe mode. Though the truck only seemed to have limited speed with the overdrive off. When it was just driven normally the transmission was not changing gear around 30 mph.

Stop messing around…Take the truck to the dealership yourself and have THEM run diagnostics on the entire powertrain…Independent shops are out of their league with this stuff…