Hopefully Mark will show up to help you - but it sounds like a mechanical tranny failure (snap ring or something similar...)

The codes you threw are un-related - mine tosses those.

 

Ouch - I hope not - I was thinking shift solenoids or pump pressure. We'll have to wait for the guru.

 

Whenever I see unrelated codes pop up at the same time as an issue, i look for electrical issues. Start with the simple stuff like the battery terminals, battery to chassis ground, engine to chassis ground, alternator performance, etc. Then move onto the trickier stuff like loose wire connectors on the main harness connectors. The 4R100 is electronically controlled so a weird electrical issue could make that run funny too.

 

It could be something electrical, but usually an electrical fault will immediately set a code. Those tests are very robust.

I think something mechanical broke, but I can't be sure without looking at the truck.

 

It could be something electrical, but usually an electrical fault will immediately set a code. Those tests are very robust.

I think something mechanical broke, but I can't be sure without looking at the truck.

I tend to agree. I hooked up AE this evening and went for a drive. Trans fluid was stone cold...as cold as it can get on a 95* day. It shifted fine all the way through OD for the first few miles. Then as the trans temp got up over 140* it wouldn't shift to 3rd again. It also seemed to be slipping more this time. I also noticed that the bit value for the VSS remained at 0 for my datalog. Unfortunately I accidentally overwrote the datalog where the trans temp was cold, so my data starts with the trans temp at 143*.

Mark if you have any parameters you would like to see I can datalog them for you. Thanks for your help.

 

I was towing farm machinery to our new place, trans was fine other than a harsh at times 2-3 upshift, unloaded all equipment and went to leave, all I had was low gear as trans ate itself. 293,000 almost to the mile miles on the tranny 1999 OEM.

 

I just got off the phone with Brian at BTS. I have got to say, he is a stand up guy. I was on the phone with him for half an hour as he walked me through some diagnosis. I am going to pull the pan and check the 2-3 shift valve. It may be sticking due to wear. I'll take a look at it and go from there.

On a side note. I am shocked and thankful that Brian was willing to take time to walk me through this (you just don't see too much of that type of customer service these days). I know what half an hour of shop time costs. If this is his customer service on a non-paying customer...wow! Top notch. I thanked him several times for taking his time with me. It is very refreshing to deal with someone like Brian.

 

Well I fixed it this morning. Stuck 2-3 shift valve, just like Brian suggested. My only concern is that the fluid (had 20-25k on it) was black. There was quite a bit of friction material in the pan as well as some metal shavings. Looks like I'm still going to be replacing it soon.

 

Glad you found it and will be on the road again.

Arkansas will be nice this summer....

 

Thats cool Brian Helped you out...

I was put on Hold for 20 minutes and they hung up . EPIC FAIL.

 

one more vote for Brian at BTS being the man of the 4r100.
Mine wouldn't shift out of 2nd gear on a camping trip last week. Drove 320 miles across Ohio in 2nd gear @ 35mph pulling 5k lbs.
Local tranny shop said I need new trans. Called Brian, he says, no way. If you got reverse and no slipping, then trans most likely ok. Probly a stuck 2-3 shift valve.
24hrs later, I'm out the door for $370 instead of $3700
Was exactly that, stuck 2-3 shift valve. Like the OP, mine has been having substantial amounts of metal in the pan every fluid change, but they've been telling me I need a new trans for over 100k miles. I'll run it till it quits.
Thanks a ton Brian!.

I sure hope I never need a trans but if I do, you know who's trans I'll be using.

 

Figured I would update this thread....


After fixing the 2-3 shift valve the trans went on to stick on the 1-2 shift. I called Brian back and talked to him for a bit. We talked about the metal in the pan and how the shifts have become more drawn out over the past few months. Bottom line he thinks the converter is coming apart. I decided to go ahead and upgrade. My BTS trans arrived today. I'll be installing it tonight after work. This trans issue became one thing leading to another. I checked my up pipes and they were leaking, so I installed IH bellowed up pipes, replaced my adapter plate that the starter mounts to (starter bolts constantly backing out), bought a 38r, gutted pedistal, high flow outlet, FRX, HPX and 6.0 cooler. So I've been busy when I can squeeze in a couple hours after work. I pulled the trans Monday night, pulled the flywheel and r&r up-pipes lastnight, will install the trans tonight and flush all the cooler lines. I have a big trip coming up pulling the 5th wheel and didn't want to take any chances....so I spent some money. I'm pretty excited to get it all back together and go for a ride.

 

Better get that tuner back to Jody for some updates....

 

Is the cooler going to be replaced with the 6.0 cooler?

 

Yes. And the 6.0 cooler is brand new. Found it on craigslist for $60 a while back...glad I never got around to installing it.