anybody have any ideas? i made a road trip in my 94 cc idi turbo with a e4od today. i went to michigan with a 14,000 gvw equipment trailer and picked up a john deere 60 tractor roughly 6,000 lbs plus some extra rims and tires and a few other things. trailer, tractor and all extra's was right around 9,000-10,000 lbs. everything was ok except the torque converter starting unlocking, driving down the road in overdrive, unlock for about 2 seconds than lock back up. well it won't lock up in low gear when taking off from a stop, and at low speeds it doesn't want to lock up at all in 2nd. the fluid is fresh about 5,000 miles since it was flushed, and at the same time i put a rv trans cooler on it so the trans is not getting to hot. anybody got any ideas? could the speed sensor be messing with it? let me know what you guys think. thanks, pete

 

Was the trans hunting....ie going in and out of OD while towing. What rear axle gear ratio do you have...... Did the RV trans cooler piggy back the OEM one ie 2...

Do the tach and speedo work flawlessly..........

 

Bad grounds in the trailer light wiring can give power to brake lights circut when not applied, this will kick the torque converter lock up clutch off. Do the trailer lights flicker and or do anything out of the ordinary?

 

cornbinder,
I suggest getting a OBD code reader for your truck and use it to help diagnose your problem. I used a code reader on my truck (1990 F250 7.3L N/A E4OD 4X4 4:10 A.R.) to determin that the FIPL was sending an intermitant signal to the TECA and cause the torque converter to keep locking and unlocking. Good Luck. Jim

 

You did not mention it throwing a code ( o.d. switch flasing) i assume it is
in that case have th ecode pulled to make sure what it is. In my 94 i have lost 2 t/c in 5 years the last time i had a billett converter put in, i hope it is the last. When you are pilling that heavy of a loud i take mine out of o/d until i hit 60 ,and if the tranny is still searing for a gear i just slow down and run in 3rd.

Good luck and hope it is just wireing

 

no i havn't pulled any codes yet. i wasn't even aware that i could. where is the plug to hook up the code reader to? i replaced the o/d button along with the whole gear shift assembly and end cap on the o/d button, ford had it in stock and my cost was only $42 and some change. i did that about 6 weeks ago. i drove the truck yesterday and it was just fine, empty no load on it. i just put a trailer brake controller on it last week too. i'm gonna pull the codes and see what i get.thanks, pete

 

Code reader plug is just under the hood at the firewall, drivers side. From what you say, my bet is with trailer wiring, I ended up replaceing a TC after towing a U-haul with screwed up lights!

 

Yeah, those lights can play with the torque converter. I had a burned out left turn signal bulb this week and when I would use my turn signal, the torque converter would unlock. I had just installed a remote starter, so I was worried that it was causing some kind of interference, although electrically, the remote starter is invisible when it's not being used. However, when I replaced the turn signal bulb, the transmission started acting normal again. Quite a relief that it was a simple problem and not a wiring issue.

 

that's pretty messed up the wiring can cause the t/c to unlock. problem is i don't know whether it's in the trailer wiring or the trailer brake controller i just installed?? i've been driving the truck with no trailer hooked to it and it's working just like it's supposed to. when i was hauling no lights were out, you guys think it's a ground or the way i may have it wired? thanks, pete

 

IMPO, its pretty messed up that ford would even design a transmission that can be affected by bad trailer wiring.

what you an try is to tow the same trailer except with the electrical hookup unplugged to see if theres any difference.

I think its also possible that higher relative throttle position could be a factor, since it takes more to hold the truck at cruising speed with a trailer behind it.

 

also i remember , during the first half of the trip when the t/c started acting up every time i hit a bump in overdrive the t/c would unlock then lock back up. what part of the trailer wiring is the culprit? anybody know? later, pete

 

When ever the trucks brake light system has pwer applied, the torque converter unlocks, makes sense as you dont want the truck to be pushing with the brake pedal applied. So if you check out the brake light system on the trailer- bad grounds for any of the lights-esp running/clearance lights, will put power back down the brake light wires making the PCM think the brake is on-unlocking the TC.

 

yeah your right on the brake unlocking the torque converter. is there a torque converter lock up solenoid? the problems i've been eliminanating, leaves me to whem i'm loaded down heavy pulling. when i come to a stop and go to take off the t/c won't lock up and it slips when taking off from a stop and i really have to play with the gas pedal to get the t/c to lock up in 2nd. gear it will lock up in 3rd/4th but it leaves the t/c slipping in first and second and it makes me nervous that the excessice slippage will do damage to trans or t/c. any ideas? your guy's input has been greatly appreciated and helpful! thanks, pete

 

As i recall, but not possitive, my trans guy told me the t/c does not lock in 1 st or 2 nd unless you manually shift, it will lock in 3 rd and over drive. Is the over drive selector blinking or not? If it is not locking properly it should throw a code.

 

The lock-up solenoid is located on the solenoid pack inside your transmission. Unforturnately this solenoid is part of a pack of 5 solenoids or so. I replaced it once on my 91 F350, quite expensive but easy to change.

Note, the tranny controller controls the lock-up of the torque converter. The torque converter will only lock with the shifter in OD and you must be off the brake (i.e no brakelights on) and you must reach a speed of about 38 mph (58km/h) before it will lock automatically. It will unlock automatically if your speed drops below about 30mph (50km/h)

Your can take manual control of your torque converter like I have done on my 91 F350. Refer to the attached thread for more details on how to do this. It is not very complicated all you need is a couple of toggle switches and a little wiring. Be careful thou this modification is not for the faint of heart because if you forget to flip the toggle and unlock your TC it is like forgetting to clutch a manual tranny. Could do a lot of damage.

https://www.ford-trucks.com/forums/4...ml#post3388209

One last thing, if you torque converter clutch is slipping you will know because as you apply throttle the clutch will slip and make a slight grinding noise which will eventually destroy your tranny if you let it go as the metal fillings end up in your oilpan. Installing the above switch will help you better diagnose if your torque converter clutch is slipping. Note the Factory OEM torque converter clutches were not very good. The clutch plates are in the torque converter so if you are slipping you need to change the converter.

Good luck with this..


Seb.....