Install regular light bulbs back in the truck or you will have to install resistors in the wiring for the LED bulbs. The low resistance of the LED bulbs is confusing the computer and you will have issues like this. I would see this issue a lot back when LED bulbs first started to hit the market, it was a tough dianoisis for us on the first one we had, I think we replaced the PCM and Speedo head before we figured it out. Lol!

 

 

Following up with the purpose of closing out this tread.

Last week while back at home from the vacation fishing trip, I replaced the Third Brake Light socket that Ford refers to it as "High Mount". Knew I had an extra light socket from an earlier JY extrusion I was on. Cut the old melted socket out and solder in the newer socket. Replaced the bulb, test drove the truck and everything is working as should, shifting into Overdrive and cruise control engages.

 

Follow-up from recent 16-19 September 2018 fishing trip. As I indicated in my 24 July 2018 thread, I had changed the previous melted third brake light socket and then test drove the truck and the E4OD transmission shifted as it should and into overdrive, no problem. Well before we left the lake 19 September 2018 to return home, I installed a LED bulb into the third brake light socket and the transmission would not shift into overdrive. About 20 miles from the lake I pulled into a parking lot and replaced the third brake light LED with the right incandescent bulb and transmission once again shifted perfectly. I really wanted to use the LEB bulb in the third brake light because omitting allot less heat, preventing premature melting of the plastic socket, but cannot.

 

You can use the LED's, BUT, you will have to run what they call load resistors in parallel... FYI In series won't do it..... The resistors put the load back on the circuit the truck is expecting...

 

Yep, gonna hafta add resistors. I bought a set that was premade and attach to wiring harness and then your LED light goes in the socket and plugs into your tail light housing. Other than that you have to go back to regular bulbs or wire in resistors.

 

White 97 xlt and Zombie F150,
Copy your advice and will look into adding a resistor. Thanks guys

 

My transmission has had weird shifting problems for a long time. I don't have a third brake light.
But I did find I had a blown tail light, which I changed out yesterday, and drove today.
It didn't seem to have as bad a shifting problem today,
So I wonder did the blown bulb cause some if not all of the shifting problems?

 

This is how I understand it.
The tail light circuit or more accurately the resistance in it controls the torque converter lock/unlock. When the brake pedal is pressed the resistance in the circuit changes and sends a signal to the PCM which then sends a signal to the transmission to unlock the torque converter.

If you have LED lights the resistance the PCM is looking for is not in the circuit and can cause the tranny to exhibit weird behaviors you HAVE to have resistance in the circuit, either by using regular incandescent bulbs or adding resistors, which is what I did, then I removed the bi-metal flasher from the truck and got an electronic flasher. So far so good. That is how the E4OD works, if the PCM doesn't control the tranny because it is not an electronically controlled tranny then it shouldn't be an issue unless you have hyper flash or no flash (because not enough resistance),which is fixed by changing the bi-metal flasher out for an electronic one.

 

Ok now I am lost. I do know I have regular 1157 bulbs.I did replace the flasher at one point with a heavy duty one, whatever heavy duty actually means, I have no idea.

I just figured heavy duty was better than the stock flasher that stopped working, so I bought it. I have no idea if that corrisponds with the time the transmission started acting up or not. I just don't remember.

 

If you have not changed out the regular bulbs and only swapped out the flasher then that is not the cause of your shifting issues.

What type of transmission do you have? the E4OD is the only one that is electronically controlled and is affected by using LED lights to my knowledge

How a bi-metal flasher works is there are two pieces of metal that make contact in the flasher and they are different types of metal one heats up faster than the other ,as the current flows through those 2 pieces of metal, one heats up and curls away from the other,breaking the connection, when it cools it snaps back to touch the other piece of metal and start all over. That is what causes the clicking, a heavy duty version can handle more current.

 

It is the E4od in my 93 F-250.
To me it's a POS and is the worst transmission ever made.
At the very least I'd rather have a C6 or better yet a manual transmission, but alas I'm stuck wit this POS.

 

My E4OD seems to be doing pretty well. Like anything ,some last longer than others due to how they were taken care of.

 

The E4 is essentially a C6, by the way. It is simple compared to most electronically controlled transmissions.

Most people who've had one since new managed to get 100-200K miles of reliable service.

Time finds all weaknesses & Ford has made continual progress improving them.

They frequently suffer from dirty plugs/connections, chaffed wires & a computer, in your case 25 years old & in the worst place possible which still works most of the time, even breaking down.

Don't see anywhere that you ran codes.

Do you use a 386 computer & windows 95 by the way?

Just sayin.