So i had some intermittent power and stalling a while back. I've put some time into the truck, sealed up the cab lights. I had all circuits that pertain to the CPS rebuilt in the ECM. So far I've got 60 miles on it with no problems. Hopefully i'll pass a rain test soon. But I'm going to continue to seal up anything I can.

Any way the transmission doens't seem to shift at the right times. I believe its a 4 speed. speeds at around 35-40 I think it stays in 3rd. I'll speed up just because I know it wants to shift, it'll shift and stay. I think to day some time, I think it got confused and and went from 3rd to 4th and to 3rd again. This was with a 4k boat on the back.

I think it's the second transmission. I bought the truck with 201K miles, It has I think 6 inches of airbags on the reat wheels, so I think it was used for some heavy loads. It did have a tuner in it when I got it, but I had someone remove it and went back to stock..

Does the ECM send inputs to the transmission? After the Tuner has been removed, is it possible the ECM needs to be reprogrammed? I don't have any CEL's the engine is running great I'm getting about 12MPG... I don't want to believe the transmission is bad yet, it doesn't seem to be a hard shift, Maybe once or twice Ive heard that. But seemed normal.

They're good trucks, But I've learned that smooth and quiet is not a standard to shoot for.

Thanks for your input

 

The PCM (that's what Ford calls the ECM) tells the transmission when to shift. The first thing to do is get the codes read. The places that read codes free CANNOT read these codes. You need either a good independent shop or a Ford dealer.

 

As comparison, mine, being all stock but with 4.10s and 285/75-16 shifts to 4th at/around the 40mph market

 

that sounds about right in my case as well.. If you were to stay at about 35..would it just stay in 3rd?? Could you check?? Hahaha. That means you get to drive your truck..

 

Mark.. Would there be codes even without check engine lights??

 

it would stay in 3rd..when slowly down under 25mph, you can feel the tq "release/unlock"..

 

Mine ****s into 4th at around 42 MPH but if I am on an incline of any sort that is too soon for my liking and I will lock out the OD on a lot of secondary roads. If you are towing and lugging the engine the transmission will 'search' between 3rd and 4th. When towing you would be best served to keep your truck in a gear that puts the RPM's at 2000 or more.

 

Thanks guys..good info.. I'm thinking my tranny is just normal.. It can't figure out if it identifies with being in 3rd gear or 4th gear at 38... Let's just call it normal....

My gears shifting doing just like yours..

 

There can be. The Check Engine light is only turned on for codes that are deemed to cause an increase in emissions. Codes that won't cause an increase in emissions will not turn on the Check Engine light.

Most transmission codes will flash the OD OFF light and will not turn on the Check Engine light.