5r55e - Using IDS & VCM to troubleshoot no 3-4 shift

[drdoom]

Does the internal harness check out?

 

[ImConfused666]

The internal harness checked out fine. Just to be sure, I plopped down the money to replace it today, as well. Just reinstalled. Same exact problem. No 4th or O/D. It does throw a P0734 and P0735 error code (just as before) but that doesn't really help me in this case. I've got engine braking in Manual 2nd and Manual 1st and three sets of eyes that have checked everything we've done. We've each carefully read each section oof the ATSG book and look at all specs. We checked for any excess play in anything and everything is well within spec. I am totally flustered. I keep thinking that there must be something outside the transmission that can cause this. I'm starting to wonder if the PCM just happened to develop a problem at the same time. We're right at $1,000 into this transmission now and I'm wondering about just putting a match to it.

 

[ImConfused666]

We also replaced the Torque Converter but I'm wondering if it's possible that it could be bad and is causing a problem? I've never really been sure how to check one out.

 

[thefatman]

Hey way off topic but maybe someone here can help! In the ids reflash menu is it possible to reflash a pcm from auto to manual tyranny?

 

[Fireside3]

I don't have access to the IDS I was using anymore, but off hand I'm going to say probably not. I can't give a definitive answer except to say that when I replaced the PCM I had to download the reflash programming that was specific to my VIN, and if you switched trannys to a manual when your VIN is going to reference an auto when motorcraft sends the programming down to the IDS, and pinout on harness is not going to be same for a PCM programmed for manual...then I don't see how this could work at all. You're going to have to swap for PCM from a manual at a junkyard and be sure to get the VIN off that scrap Explorer.

BTW, I picked up a salvaged PCM off ebay for about $40, worked like a champ once I flashed it with the IDS, cycled my old keys in the ignition for PATS to accept, and as back on the road...if only in 1-4th gears, but it's running.

 

[Fireside3]

Well, since it pisses me off to no end when people don't post follow ups when they get a resolution...

I had performed the band adjustment over a year ago to try to troubleshoot this, but that torque wrench was a deflection type, and had seen better days. Apparently it was off sufficiently enough to prevent a fix, and so I went off looking for other causes, which were frustratingly dead ends. I went down and spent $14 at Harbor Freight for a click type, and that made all the difference.

Adjusted bands, 120 in/lb, 2 turns back, Hallelujah...my X has just hit shifts after TC lockup for the first time in over a year. It's nice to be hitting 70mph at 2500rpm instead of 3500. No more flashing OD light. I have 243,000 miles, and yet I didn't need a reman valve body like many suggested. Maybe later, but for now a huge frustration has been lifted.