2016 transmission replace/rebuild, reprogram?

[tom3]

Son's Sierra has the 6 speed transmission, 5.3 engine, just hit 100k miles. Transmission started a minor jerking at easy cruise, light acceleration, then let go completely. Fluid brown and smelled. But the question - Looks like a reman. unit has to have the TCM reprogrammed? If we take the original transmission to a local shop and get it rebuilt with a new converter will it work without any reprogramming? We've had a couple older transmissions rebuilt by them with very good results. We do the R & R and they are pretty reasonable.

FWIW, he's a school teacher, 3 kids, just got the truck paid off, dealer service on this is out of the question.

 

[SundayMech]

Have you tried transmission fluid change and filter change?
I would do that first if that fixes the issue; also would be the most cost effective way to start.
Hard to think a 2016 transmission with just 100k miles would have re-manufactured.

 

[NickTransmissions]

Son's Sierra has the 6 speed transmission, 5.3 engine, just hit 100k miles. Transmission started a minor jerking at easy cruise, light acceleration, then let go completely. Fluid brown and smelled. But the question - Looks like a reman. unit has to have the TCM reprogrammed? If we take the original transmission to a local shop and get it rebuilt with a new converter will it work without any reprogramming? We've had a couple older transmissions rebuilt by them with very good results. We do the R & R and they are pretty reasonable.

FWIW, he's a school teacher, 3 kids, just got the truck paid off, dealer service on this is out of the question.

Have you had this rebuilt as of yet? What are/were the symptoms as of Apr 27th? No movement, slipping/grinding/wrong gear starts, etc?

If not done so, Take it to a shop well versed in these transmissions so you receive all the requisite corrective parts installed and procedures performed. See my 6L80 Info thread for a complete list, if you havent already.

Have you tried transmission fluid change and filter change?
I would do that first if that fixes the issue; also would be the most cost effective way to start.
Hard to think a 2016 transmission with just 100k miles would have re-manufactured.

Waste of time, money and fluid if the unit went out as he's insinuating. If the fluid at the dipstick stinks, its likely done. He can always plug in a two-way scan tool, drive it around (assming it will move - if not, moost point) to view live data to confirm to a certainty what he strongly suspects.

 

[tom3]

Transmission was working fine. Started getting what like an engine miss, random, at easy cruise and light acceleration. Thought maybe some bad gas? After sitting for a couple days he drove it and could just slightly feel it. Then the next day was pulling on the highway and smelled sulfur (?), started jerking, then the trans. went into full neutral and the check engine lcon lit up. Had been making a noise sort of like an old power steering pump going bad, then real bad. Going to unhook the battery for a day or two, (clear code and reset?) and retry the transmission to see if it will work. He called a law firm that's working on a class action suit on the GM transmissions, call center guy said there were 10 people in the call center taking calls on this, all busy all day with calls. Kind of amazing how the AFM and the slipping lock up converter can destroy the reliability of a really nice vehicle. I did point him to your post on here to get some real info.

He's driving his bad weather machine, a 96 Jeep Grand Cherokee, 240k miles on that machine. That old inline six will probably be running when the body has disappeared.

 

[NickTransmissions]

Transmission was working fine. Started getting what like an engine miss, random, at easy cruise and light acceleration. Thought maybe some bad gas? After sitting for a couple days he drove it and could just slightly feel it. Then the next day was pulling on the highway and smelled sulfur (?), started jerking, then the trans. went into full neutral and the check engine lcon lit up. Going to unhook the battery for a day or two, (clear code and reset?) and retry the transmission to see if it will work. He called a law firm that's working on a class action suit on the GM transmissions, call center guy said there were 10 people in the call center taking calls on this, all busy all day with calls. Kind of amazing how the AFM and the slipping lock up converter can destroy the reliability of a really nice vehicle.

He's driving his bad weather machine, a 96 Jeep Grand Cherokee, 240k miles on that machine. That old inline six will probably be running when the body has disappeared.

So the vehicle doesn't move at all, regardless of whether it's in R, D or Manual mode? If so, likely torque converter crapped out and destroyed the pump though you can quickly confirm/deny the pump rotor/slide are intact by checking line pressure with a gauge on the driver side of the trans, behind the bell housing. Fire it up and see if there's any pressure on the gauge. At idle in P, N and D you should 55-80 psi, steady. If you see nothing, pump is destroyed.

Id also scan it to see what codes you have and post them here. My guess is P0741 (converter clutch solenoid stuck off and/or P2762-performance) if the TC is bad.

Unfortunately, these converters often damage/destroy the pump when they break bad. Symptoms can also be associated with front gear set failure, rear gear train, 4-5-6 clutch hub snapping in half (gears 1-3 will still work if this happens), #1 and 5 check balls getting stuck in the separator plate and/or migrating out of their respective locations.

There's several separate pieces of CA litigation but think they are all related to the 8 speeds (an even bigger dumpster fire of a unit). Didnt know there were suits tied to the 6Ls as well....

If you decide to rebuild it yourself (or with your son), my YT channel has a fairly extensive playlist on these units so would be a good resource for you.

Let us know what you find out and post back with any questions.

 

[tom3]

Thanks for the response. With the noise it was making, and it did sound like a shot hydraulic pump, I'd guess you are right on target. Over the years I've done about everything there is fixing cars/trucks except getting inside an automatic transmission. Not going to start. This has him pretty upset, let it sit for a while, lay away some cash as possible. Maybe a low mileage used unit, might be hard to find, and then there's the TCM reprogram deal.