Help, I have an 1994 ford f150.I was told if you cut the purple and yellow wire on the tranmisson harness,that it will stop lock out on the torque converter. I was told it is better not to have a lock out, that the transmission will stay cooler. I cut the wire, and it seems that it sifts alot better.I was getting a buck every know and then.I haven't had it buck on me since I cut the wire.Engine light has not come on,yet.Is it going to hurt the transmission with the wire cut.Please help!!!!!

 

Howdy and welcome!

Umm, whoever said that was wrong...

Popular mod to actually run a switched power lead to that wire to lock the TC on command. An unlocked TC builds heat from the slipping.

I'd recommend a pan drop, new filter, drain TC, and refill with fresh fluid. A stacked plate tranny cooler added in up front will also keep the temps down.

Which trans do you have? Trans code E on the door jam sticker would be the E4OD and requires Mercon. Code U is the 4R70w and requires Mercon V.

Adrianspeeder

 

Hi! I have the e40d tranmission.I just had the rear main seal change.When they change it they also change the transmission fuild in transmission.I had a buck in the truck before they did this.I had some one tell me that it could be the ttc sylinoid sticking.this tranmission has the sylinoid pack.The purple and yellow wire was cut and I haven't had it buck on me yet.Could it be the sylinoid pack.If so, should I have it changed and hook the wire back together?SO,IF IT DOSEN'T GO IN TO LOCKOUT IT WILL HURT THE TRANSMISSION?

 

I'd suggest that you consult with a local competent transmission expert and have the original fault diagnosed and repaired.

Forget the "mods" if you don't understand their potential consequences.

Steve

 

If it doesn't lock up the trans can overheat. That can kill it. You also will lose 3-4 MPG without the lockup.

 

Well, what you were told is partially correct...... The reason it was 'bucking' was because the torque converter was locking up.... But the FLUID was probably shot..... Change the FLUID and the bucking should stop when the TC locks up...

How often do you have your trans serviced?? It should be every 30,000 miles at the most.... I do mine once a year because I do tow with mine.

Your trans is designed to "lock"... If it doesn't, it'll get really, really hot, and that will kill everything else inside it...

I'd splice those wires you cut back together, do a complete fluid change and if the bucking still occurs, then you have a bad converter IMO... If you continue with your existing setup, all you will do is fry the rest of your trans in due time...

Good luck!

Mitch

 

Thank you guys for your help!I put the wire back together today.If I GET ANOTHER BUCK,i'M GOING TO HAVE THE TRANMISSION FLUSHED.do you think that would be the best thing to do,first.Also could it be the computer making it buck.It is not all the time when it does it just when it wants to.I have 107,000 miles on it.I pull a trailer every now and then with a mower on it.I take good care of my truck.I had it since it was new.1994.I change my oil every three thousand miles and keep the belt changed.I've changed these parts thiking this was causing the buck, map sensor,throttle position sensor,idle air control valve,oxgen sensor,egr valve regulator.Also, it seems like when it is cold in the morning it stalls in reverse. only one time though.start it again and it backs up fine.Crazy.Any suggestion?

 

The stall is probably a trans fluid problem. Low fluid, or very old fluid could do that. If you want to flush it yourself, you can seave a bunch of $$$$. Use this method to do it: http://www.ford-trucks.com/article/i...nsmission.html

I'll bet the bucking is caused by one thing that you missed in the parts changing frenzy: the ignition coil. I forget if your year has the coil on plug, and if it does, the misfire code is a big clue that the coil for the 5th cylinder in the firing order is bad.

 

The other thing that can cause a 'bucking' in the trans is when the speed that you are going is right at that point that the computer is telling the TC to "lock", but then is also telling it to "unlock" as well.

That happens to me whenever I am coasting and then give it gas for a second and then have to let of again for traffic or whatever and if I'm at that 'right' speed while doing it, the TC will 'buck' on me as well.

If you are feeling more of a 'shudder' in the truck when it up shifts, especially into OD, then that's more likely the TC itself or old fluid.

Should have mentioned this first, but there you go....

Mitch

 

Thanks guys! I will keep you posted to let you know the probelm.