Help identify an issue - Skipping/Shaking

[1SLOW1500]

I am leaning to injector after you go with plugs and wires. But I would pull the intake off clean everything then before you touch anything go through the coil pack harness. If you are replacing injector just do all they are like $60 each then the 2 fuel lines.
As I said before you can see bad injector by scanning the o2 sensor on that bank and pulsing the injectors one my one you will see the afr go up and down vs demanded afr. Basically a % of error in the o2 bank over commanded afr.
Most shops just throw parts at it till it works.

Sent from my SM-N960U using Tapatalk

[L86 All Terrain]

Buy a $100 scan tool if you don't have one first of all. At least it will tell you what cylinder is acting up. If you put all new wires, coils and plugs, you should have good spark, if their is no miss detected on a cheap scan tool, it is likely a fuel delivery issue. I would investigate the injectors. Are you sure it is an engine misfire? Could it be a bad torque converter vibration? I have had 1 new TC and 1 new Trans, felt like driving over a rumble strip/engine vibration when it acted up.

[Ozer]

5 hours ago, L86 All Terrain said:

Buy a $100 scan tool if you don't have one first of all. At least it will tell you what cylinder is acting up. If you put all new wires, coils and plugs, you should have good spark, if their is no miss detected on a cheap scan tool, it is likely a fuel delivery issue. I would investigate the injectors. Are you sure it is an engine misfire? Could it be a bad torque converter vibration? I have had 1 new TC and 1 new Trans, felt like driving over a rumble strip/engine vibration when it acted up.

I thought it could be trans issue but torque shows many misfires in #3. If it was TC, i shouldnt see any misfires correct? It could be multiple issues who knows.

[1SLOW1500]

I thought it could be trans issue but torque shows many misfires in #3. If it was TC, i shouldnt see any misfires correct? It could be multiple issues who knows.

Misfire is 100% seperate from trans issues. If you where just feeling something I would say trans but a logged misfire is that.

Sent from my SM-N960U using Tapatalk

[newdude]

Dealer can run a fuel injector balance test the with GM AFIT tester.  That will call out an injector really quick. 

 

[Ozer]

35 minutes ago, newdude said:

Dealer can run a fuel injector balance test the with GM AFIT tester.  That will call out an injector really quick. 

 

That is my next step i think. I will check the coil wires and such this weekend and swap a plug wire with another one to eliminate those chances.

[Ozer]

23 hours ago, 1SLOW1500 said:

Misfire is 100% seperate from trans issues. If you where just feeling something I would say trans but a logged misfire is that.

Sent from my SM-N960U using Tapatalk
 

Just dropped it off at the GM dealer and they called and said ots def not a misfire but its a TC shudder. 

Not sure why TorquePro showing me misfires but yeah..

He is going to pull the pan out and see the damage and what it needs. New TC or a new trans.

Whats anyone's experience with this TC issue?

 

[1SLOW1500]

I am unfortunately a pro on this now.
This is the 6l80e?
Are you in warranty?
This is very expensive land.
Service to remove and reinstall alone is $600to 900 depending on 4x4 and exhaust.
Stock TV suck and will always break down. And hope trans is ok. They are around 4k

Sent from my SM-N960U using Tapatalk

[L86 All Terrain]

I have a 6L80e that has some serious problems, but not related to the T/C, it's AFM related. My 2015's 8L90e has had a T/C and eventually a replacement trans. The bill for a reman trans (under warranty) would have been $6,000 Canadian ($4,450usd). I forget what the TC job cost as it was done before I even took delivery of the truck. 

 

You can get a new TC for a 6L80 between $200-800usd for a basic T/C (no high RPM stall) depending on quality level if you have no warranty. But as SLOW said, the labour is the big cost there, probably around 1800-2000usd for a swap. I would buy an aftermarket converter anyway with GM's recent track record with these many-gear auto's. 

[1SLOW1500]

The stock tc is a single disc and with the afm and DOD the trans is set to slip al lot this causes lots of extra wear and heat. This is why there is now D6 fluid. But that still isn't enough with the factory temperature locking the heat up to 209*. 

Anyways if it is under warranty I would get them to replace all of it then spend the little money on a good tune to disable those and change up tans. Good guild and a modification to the trans manifold your good to go. If out of pocket I would find a good performance shop and upgrade stall. And tune. If the trans is toast....well first I am very sorry. Then. Phoenix and CDT  but really cdt. As said $4000 is the stage 2. And there brother company makes the best stalls also. You will still be over 6k but ahead of the game.

[Ozer]

Update:

The dealer said the TC crapped out, there was metal and bushing pieces stuck to the magnet and down in the pan. He was amazed that i was still driving it like that. I didnt see the pan myself.

Anyways i got quoted for a "new" trans from the dealer for $5000 and some change out the door. They said rebuilding would cost about the same if not more which i thought was BS.

Called up a transmission shop that my brother and his dealer friend knows and uses... getting it rebuilt with better parts and fixing some of the issues GM had and a new TCM for $2800 out the door. Its at the shop now. 

Hopefully i can get reimbursed if GM comes up with a recall on the TC.

[L86 All Terrain]

Glad to hear you figured it out, sorry to hear you need a rebuilt trans. At least you can bulletproof it now and not just get another lemon from GM. Chances are there wont  be any recalls unless people start getting hurt because of the issue. If you are into modding your truck, now would be an excellent time to do a higher RPM stall converter if you aren't covered under GM warranty. That seems like a good price if they are giving you a new TEHCM and not pulling your old one out of the pan. 

[1SLOW1500]

You would have been best calling cdt. A stage 2 is less than 4k. Also I would buy a performance TC. As we all know they aren't great.

Sent from my SM-N960U using Tapatalk

[Ozer]

8 minutes ago, 1SLOW1500 said:

You would have been best calling cdt. A stage 2 is less than 4k. Also I would buy a performance TC. As we all know they aren't great.

Sent from my SM-N960U using Tapatalk
 

He is putting in a beefier TC not the stock GM. I felt more comfortable with getting it done by the local guy we know. This way i drop off the whole truck and pick it up. No need to remove trans and install new one.

Thanks for all the help. Ill update once its done. 

Then i will look into why i was showing misfires in TorquePro. 

[Ozer]

UPDATE:

Got the truck back yesterday and its all fixed. Fresh rebuild on the transmission with better clutch pack, shift kit and a better TC.

The guy who rebuilt it is very knowledgeable and performed the updates and fixes that these 6L80 trans need.

He did the thermostat delete as well.

 

Truck shifts nice and no issues anymore. Hoping this will be the last time this trans is touched on this truck for the remainder of its life (besides oil changes)

Friends and Family discount of $2700 out the door. 

#ThanksForNothingGM