2011 Chevrolet 2500HD, 165K miles. 6l90 transmission. Thursday evening I was headed to pick up a load of hay and do some dove hunting in the panhandle. I was empty and had the cruise set on 80. Went through a small town and hit resume on the cruise on the edge of town. RPMs shot up over 4500 and went back down. Got going again and trans temp got up to almost 240. I stopped, checked fluids. Fluid was full and looked good. Let it cool off and tried to get going again, still same issue and the check engine light came on P2700, P2011 and P22534. We loaded my truck on my trailer and a buddy hauled us the rest of the way. We took it to the dealer in Pampa on Friday morning, they took my $170 and quoted me $8K to replace the transmission.

After a little research, someone suggested the TCM. Does any have any other insight? Do I throw a TCM at it and see if I get lucky, or go ahead and find another transmission? I need it to last another 12 months or so!

On edit, I drove it almost 300 miles home without the trailer. Had to be real sensitive with the throttle climbing hills and it would shift hard in 2nd and 4th gears. Temp never got over 175.

Pull the trans dipstick and put a few drips of the oil on a white sheet of paper and see what color it stains the paper. If it's brown or black you've got internal transmission problems. If it's nice and red you probably have some control issues and I don't mean your personality.

Draon fluid and add a bottle of Lucas transmission fix then fill with trans fluid. Turn the truck on, let it warm and manually shift through all the gears a couple times without moving the truck. Then drive the truck like a manual for a few miles. See what happens.

Look up the codes on the interweb and see what it says.

Call Watson Transmission in Denison, TX. He's a straight shooter and won't BS you or sell you a bag of dog poo.

I had the identical issue on a newer Chevrolet, probably on the same stretch of road. This was while pulling a trailer. It was my transmission thermostat. They replaced it, dumped pan, changed fluid and filter, problem solved. Do you have the external thermostat, on drivers side?

Buddy had that same model with the same issue. He replaced the transmission. Chased down electrical gremlins for a month and finally gave up.

cant help ya on trouble shooting but had one replaced/rebuilt on a 2015 at 150k. last year it was $4k. kinneys transmision in terrell

I’m a firm believer in trying the simple things first.
Try resetting the computer by pulling the negative leads on the batteries for a soft reset and see if anything clears up. If nothing changes at least you’re only out about 15 minutes of your time.

This. It's telling you what's wrong with it. If you fix your own vehicles, at least you'll know if you have the tools/ knowledge to do it yourself. Don't get taken by the stealership. If you do need to take it in to have fixed, at least you will already know what is wrong with it. You are armed with information which can save you lots of money.

Let me guess you don’t change the fluid?

Have an uncle went through same thing with about 180k. Local trans shot rebuilt it for him. He never serviced his either.

Have you been hauling heavy loads often since 2011 - and changed the fluid at least every 50k when hauling heavy loads?
How many times you change fluid in 165k mi? or does it still have factory fluid in it?

I live in a glass house in this case

There's a guy on a youtube, Performance Transmission, he has quite a few videos on CHevy Transmission issues.

A mask will prevent it!














Oh wait. I should've read the thread before replying.

Thanks everyone, I am about as mechanical as a trained monkey, but to me the codes read that something happened to the TCM, transmission overheated and caused an issue with the ignition. But what do I know. I think we are going to pull the pan and see what we see and go from there. I have put almost 100k miles on this truck since I bought. I might haul a load 3-4 times a year, depending. Other than that its just back and forth to the ranch. And I am guilty of not keeping up with regular service like should, I have serviced this once in almost 100k. Let the lashing begin.

A least you are honest.

If you say so

Transmission service is typically due at the 100,000 mile mark. Doesn't sound like you neglected it...unless you bought it with 80k...

Close, 70K.

If you've changed fluid at least once (around 80-100k) - that wouldn't be complete neglect.
Did you pull heavy loads in standard drive (D) (which is actually overdrive) - that coulda cooked-off upper gear clutches.

Some of those codes you mentioned are more electrical in nature - how old is battery?, are terminals clean and tight?, and is that still original Alternator?
Any issues with any of those three could cause electrical gremlins similar to your error codes - make sure to check all those too.
An alternator with worn brushes getting ready to go, along with an 'old' battery, can cause some really erratic issues.

I pulled the loads in manual 5th gear (out of 6) with tow/haul mode on. I have not personally replaced alternator, but battery is fairly fresh.

I guess a quick test would be to start it up and put a voltmeter on battery while it's idling - with everything electrical turned off - get a 1st voltage reading on the battery terminals),
then turn AC on full blast, headlights on, radio on, anything electrical you can think of, then take a 2nd voltage reading on the battery terminals .

Well, how much metal in the pan? magnet covered? oil look 'blacker' in the pan than on the dipstick?

The factory torque converter on these 6l80 / 6l90 's cause short life if you don't keep fluid absolutely clean (see 2nd & 3rd video below to see why)

If you need it fixed up there is no one better than Richard up in Amarillo - He can make it better than new:

Precision Transmission
Amarillo
806-372-2210

I have never changed the fluid or filter in 211,xxx miles in my Ram transmission.

I thought Ram/Dodge transmission were supposed to fail before they got off the lot

Take it to Kenny Wilson in Gainesville , 940-665-8438

I bought a GM TCM off Amazon, should be here tomorrow. We are going to pull the pan on Saturday and see what we see. If everything looks good in the pan, we are going to put the TCM in and see what happens. If the pan looks trashed, I'll go get a reman transmission and call it good and send the TCM back.