Ok, I asked about 4 months ago about this and decided I would ask 1 more time before I drop the tranny.

Ok, I was pulling about an 8,000 lb trailer. Its been awhile so the speeds may not be exact. I just pulled away from the gastation and hit the highway in Overdrive (converter unlocked) running about 80mph and about 10 miles later is when I noticed I was just blowing smoke from the rear. Pulled over and tranny fluid was poring out from the tube from the dust cover. I let it cool and droped it in 3rd and started again, this time running about 50. I got to the next truck stop and put 2 quarts of fluid in and left in 3rd doing about 65 and again started smoking. Pulled over, let it cool drove 55, and still smoking. I ended up doing 35mph for the next 80miles till a friend met me and pulled it the next 150 miles. Ran ok after that.

Now, everytime I put a trailer behind it, it overheats. It shifts nice and hard so I don't think the trannys slipping. (Im not expert on trannys so I don't know). I feel its the converter overheating but not sure. Also, I would think if the tranny was slipping, it would be shot by now.

If Im not pulling a trailer, It doesn't overheat at any speed. Any Ideas.

 

ok this my sound stupid have u check ur wires going in the trans have u changed the fuild brand or the trans controler

 

I have changed the fluid brand and havn't tried a trailer yet as I just finished it today. I just did a fluid and filter change in hopes the filter was pluged but I could blow through the old one just as good as the new one. The magnet had a normal amount of metal. Transmission looks like it has been in for a Long time. The bolts holding to the engine don't even show wrench marks on them so It may be original setup.

I did put in a trans controller that only increases the line pressure about a year ago from banks that came with my turbo and it did shift harder under heavy acceleration which is what I wanted.

The wiring to the tranny is ok and I have no tcm codes.

The FIPL (or whatever that things called) is ok and set right. Floored it upshifts right at 3200 and downshifts when it should when passing or pulling large hills. Again all shifts are firm and feel good.

The cooler lines flow good and it also has an external cooler as well that flow good.. The cooler is clean and has no debrie such as leaves, grass, ect on it.

 

david85 should know this tranny better them but i i think theres a short some where i think it rears it ugly head with the extra elctrial pull of the trailar light

 

have you tried it with the trans. controller off ? just curious if it makes a diff.

 

Yeah Joe thats a real possibility.

Mega, why was the torque converter unlocked in overdrive @ 80 MPH? That in itself can cause an overheat condition.

Does it normally cruise like that unlocked or is this only something that happens when towing?

 

dose it happen whe u turn on the radio if i rember right it was rain and snowing when this happens and had the lights wipers radio heater and cab lights on

 

hey mega my tran does the same thing but thats with out a loaded trailer anymore and it takes me reving the motor just to get it to go in reverse after it warms up and i drive acouple of miles i also changed fluid and filter and still have problem and have not figured it out yet i just hope someone has got an answer for this

 

It was a calm cold dry night with all lights on.

The reason i unlocked the converter was because it couldn't decided if it wanted to stay in or out. It was constantly cycling so I turned them off by turning on the hazzards.

As for turning the controller off, I can't. Its hardwired to the plug. If it comes to it, i thought about removing it to see what happens but I didn't think a higher line pressue would cause it to overheat.

I know it shouldn't overheat expecially in 3rd cause I can pull a similar weight with my halfton chevy in 3rd and not have a problem and i know its the original 4l60e with 160,000 miles on it now. I have pulled tons of heavy trailers with my chevy with no tranny problem at all so this 1ton setup should be able to exceed this. I would rather pull with this cause its more stable at high speeds and brakes better.

Im taking all yalls ideas in consideration so if anyone has any other ideas I (and now PMELAH) can sure use them. Thanks again.

 

u should do a a zf5 swap

 

Running 80 MPH with the TC unlocked and towing 8000lbs isn't really what ford had in mind when they made the E4OD. The torque converter can make a LOT of heat in overdrive if its unlocked because of all the slip. 3rd gear should have been fine but maybe things were already set in motion at that point. Generally torque converter rapidly cycling on and off means a rebuild is needed or at least a new torque converter.

We had another guy a while ago that used an electronic line pressure riser in his truck and after some faulty wiring on a Uhaul trailer caused his TC to go into rapid cycling, his TC lockup let go. He got off with just having a medium duty towing/RV converter installed and put the tranny back in. Last I heard his truck is still doing fine.

The weakness of the OEM torque converter (among many others) is the converter clutch apply piston that can fatigue and crack allowing fluid pressure to leak out and the clutch can't hold (even at stock line pressure settings). The PCM will attempt to signal the TCC to apply, but after the initial line pressure spike fires, the pressure in the piston quickly bleeds out and the clutch releases again so the PCM signals lockup again, and now you have a classic TCC shudder condition. It could very well be that your TCC is still holding well enough for running empty, but is slipping when you attach a load to the truck.

One of a few reasons why I don't like products like the banks trans command is it puts extra strain on the TCC apply piston and can cause an already weak part to fail even sooner by increasing the line pressure. Higher line pressure in an otherwise stock E4OD valve body also adds more heat, not nearly as much as a slipping/hunting clutch, mind you. A good aftermarket torque converter should be able to better cope with the banks trans command line pressure riser.

Searched high and low, but I still don't know what "PMELAH" stands for.

EDIT: I should add that there is a possibility that there is a trailer wiring fault that brought on the initial TCC shudder. A bad FIPL sensor could also do this.

 

no need to search high or low for pmelah david85 that would be me but thanks for the info i how ever have an all stock 94 f250 turbo IDI and am learning alot from yall but what is a zf5 and would it fit without any mods

 

hey megacab!!how ya been?to me it sounds like ya may as well rebuild.its had alot of miles on it if i remember right and has probably served ya well.i hate workin on trannys so i know about the hesitation your having.lol

 

Man david85, thanks for the info, alot in that paragraph and made alot of sense. Thanks everyone else as well. So, lets continue.

As for the trailer wiring, which it seems to been broght up before, I had it unplugd for the first 10 miles before the gas station cause I didn't have the right plug for it. It was cycling on and off at this point. after oryliles auto parts and the gasstation, I took off, still cycling, so thats when I decided to kick the converter off about 3 miles out. So Initally, the TCC wasn't effected by the trailer wiring cause I couldn't plug it in. I was just hopin I wasn't going to get pulled over and atleast it wasn't dark....yet.

Ok, for the torque converter, you said that high line pressure can effect the stock converter pistion. I am looking at getting a heavy duty tripple clutch billit torque converter. Do you think that an aftermarket upgraded converter should be able to handle these pressures??

Joe, Id love to have a manual tranny in this but I just don't want to do the conversion. I have thought about it but it seems like alot of trouble to convert to a standard. But Then I wouldn't have to worry about slipping torque converters, line pressue, shift points, FIPL thingy settings, TCM, boiling tranny fluid, shift kits, control moduals, enguagemnet pistions, tranny coolers, slipping clutch packs and bands, ect. I can shift when I want. I had talked myself out of this and now you brought it back to thought again.

 

The way FMC worded his last sentence I thought PMELAH refered to an abreviation like LOL or something. What can I say, its past my bed time.

The ZF5 is a 5 speed manual transmission. I wouldn't call it bullet proof, but there are fewer things to go wrong with it. Drive shaft and cross member have to change to fit the ZF in the place of an E4OD. Other than that, its just a swap to manual transmission (hole in floor, install clutch line and pedal, etc).

Major weakness of the ZF is the high cost of clutches and the dual mass flywheel that can result in high cost repairs. Though not as high as an E4OD rebuild. You can swap to an aftermarket single mass flywheel but those are still around $500-$600 for the conversion kit and they cause gear clatter at low engine RPM.

MegaCab, do you know how many miles are on your transmission?