Ok 2008 f350 5.4 truck xl 4wd if that matters. Miles are irrelevant to drivetrain but chassis is 300k so here goes.

1st shifts to 3rd then almost locks transmission then limp modes it to 2nd per usual as I'm gathering. P0772 p2704 all to do with shift solenoid E I broke the trans open ohm everything and actually solenoid C was at 5.1 so I changed it but also changed E just for a haha. I tested the harness with continuity through all pins to the solenoids that all checked out here's the part I don't know yet I got a wild hair and was cross checking my other solenoids so I pinned to pin 1 which is solenoid A I tested it as good but I plugged isolenoid A back in and tested all other solenoids for continuity and they have continuity but resistance that matches the solenoid (4.7).

Are they supposed to be this way or should I change the internal harness?

If they are supposed to be this way should I look at a PCM or replace the trans as something in the hard parts is broke not allowing the shifts.

Very hard to explain and keep short but hopefully that gives a decent overview to start with

Mark if you hop on here I will gladly pay for your knowledge through venmo or however you accept payment to save me the hassle of running through diagrams. Alldata doesn't show me what I need to know

 

P0772 means that shift solenoid E is mechanically stuck. Ohming the solenoid won't show anything, it isn't an electrical problem.

If your harness were bad you would have codes for electrical faults, but you don't have those codes. So the harness is NOT the problem.

You said you replaced solenoid E. Have you driven it to see if that fixed the problem? I expect that it would.

 

Yes I did test drive it and it actually locked the trans up harder with the new solenoids to the point it actually stopped the rear wheels from spinning

 

Did you make sure to use the correct solenoids? Some of the solenoids (A and D) are inversely proportional (pressure goes down with increasing current) while solenoids B, C, and E are directly proportional, meaning they increase pressure with increasing current.

 

Yes the correct solenoids are in the correct positions. So what I'm gathering on this is the trans has an internal failure and it's time to come out. I have a second trans I just wanted to make sure it's not electrical before I put in a new transmission, this transmission is low mile and fluid was clean as a whistle so I was hoping to salvage it.

 

hi
i have a F450 with the 6.4l and the 5R110W Torqshift transmission
while driving the gears will shift on their own from gear to gear causing the truck to slam to stop or be in a low gear. seems to start after truck runs for 20 minutes or so. Any advice would help tremendously,

 

Read the codes in the PCM. That's always the place to start.

I recommend getting Forscan at www.forscan.org. Their page shows how to select an adapter to plug into the OBDII port. If you don't want to make changes in your truck, just read codes, you don't need to purchase a license.