Well, I put the sonnax valve kit in the cooler bypass line. Re-tested, and no 'backwards' spray. So I know for a fact that the valve WAS a problem, and now it's not - In any gear.

Trouble is, the stupid transmission still gets HOT. I have the wife, who hauls horses watching it using the torque app on her phone.

1.) I know the PID formula is correct, it reads accurately an ambient temperature when first turned on

2.) Fluid flow is good at the return line to the transmission.

Tonight, ambient temperature about 75 degrees, hauling 2 horses and trailer (about 5000 pounds total) up a 1/2 mile hill (not a monster, but steep enough) temp hit 238 (average speed probably around 35 miles an hour) and she pulled over, threw it in neutral, let it cool to around 205 (wouldn't go any lower than that) and drove home.

WTF? Coolant has good flow as was evident in the test after putting in the sonnax bypass valve kit. It's Mercon/DexronIII (not mercon V) fluid

Mark, what else could it be? I can't believe you need an aftermarket cooler in this truck to haul 5k pounds. Any hints as to what else might be wrong? It still seems to drive fine. Shifting is smooth and there aren't any obvious other clues.

FYI - this happens pretty predictably with a load, and on hills or slow traffic. Normal driving with no trailer is not a problem.

 

Mark you sound like you know what you're talking about with this transmission and I have been trying to get some good information on what is wrong with my transmission for probably 8 months now. I parked my truck one night and everything was fine the next morning I started it and only had reverse no forward gears and makes a grinding noise going from reverse to park. The transmission and torque converter only have 13000 miles on it. Took it to a shop in town they told me it can't be the torque converter that it was either the valve body or the whole trans needed rebuilt. I tried the valve body same issues. After a while I now have no forward or reverse and unless the transfer case is in neutral the truck will die when put into gear. I pulled the trans rebuilt it with all Suncoast parts only hard part needed was a direct drum so i replaced it also. Put the trans back in same exact issues after the rebuild so i called Suncoast and they told me the front pump was bad. Pulled it and replaced it put trans back in same exact issues as I had from the beginning. I also replaced the cooler with a bigger one from Suncoast and filled with Royal Purple and put it a ix filter. Any ideas as to where to go next would be greatly appreciated? I really really miss and need my truck and really really need some good information before I replace the torque converter next. Thanks!

 

Now that it stalls in any gear unless the transfer case is in neutral the torque converter is locked on. That could be a bad torque converter, it could be something in the trans or wiring making the converter stay locked. It is going to take some hands on diagnosis to determine what's wrong, and I can't do that over the internet. Sometimes the cheapest way to fix something is to pay someone that has the tools and experience to fix it right.

 

Here here: I didn't care to argue with Mark so simply follwed his advise for my tranny fluid puking 4r100 V10 pulling a little boat.

Solved it with a junkyard 6.0 cooler for $50 plus some fittings. Took me about 3 hours to replace tiny original cooler, install a temp gauge and flush whole works with Mark's instructions (found elsewhere on this site).

FYI, my trans has almost 240,000 HARD miles on it befire I cooled it down.
FWIW, I also yanked out my a/c condesor to cool even better as my 99 F250 has no oikt to water aux cooling. Good Luck!

 

Thanks Mark I think I'm going to replace the torque converter since that's about the inly thing left and I haven't found any wiring issues so far. All my solenouds ohm out to spec so converer can be the only thing left to replace I think haha. My only question is what causes the grinding noise any idea? Thanks again!

 

Mark
I have a 2004 ford f350 with same issues .i have the 5r110
Was kinda of delaying shifting into gear.then the other day stopped at stop sign and like put it in neutral. Put it in park
Turned off,started and it went into gear to get home.seen your thread with the bolts backing out. They are tight but only 2 picture I seen had 3
Trying to find out info on solinoids and what each one does
Can ya help

 

 

Another common problem for the 4r100 is loose of forward gears. FIX is to tighten the feed bolts problem solved, no rebuild necessary

galaxy S4 using IB AutoGroup

 

we don't know the service history or what was put in the tranny so anyones guess is anyones guess.

 

Mark

I appreciate all the info and the insight
Still have not figured out problem, a little bit of material in the pan but no big fragments ,changed both filters and new oil but still same result
Dreading calling shop
My tuner is showing 2 codes p0603 and p1000 but will start looking into codes to see
Thanks again and if ya have anymore advice I would appreciate it
Thanks
Robert

 

P0603 means you have a tuner installed. P1000 means you haven't driven enough for all the tests to have run. Neither one helps with what's wrong.

The next step would be to get a 0-350 PSI gauge and install it in the test port on the side of the transmission. You need pressures at idle in each gear position, and at stall (not moving, go pedal on the floor) in drive and reverse.

 

I have a Ford f350 with a e4od tranny. Just had put in about 6k miles ago. Wor ked fine, was pulling trailer house and started not to shift into over drive. Son pulled and cleaned said everything looked ok. Put back together and cleared codes. Worked fine on freeway pulling trailer. Got off and started to do same thing. Not shifting and over drive light flashing. Any ideas.

 

My idea would be to get the codes read. That will tell you where to start. Without the codes all anyone can tell you is that something is wrong.

 

The code reads p1748.

 

That indicates a problem with the EPC (Electronic Pressure Control) solenoid. I recommend replacing it. It is probably worn and sticking.