6l90 compatibility

[Jason 56]

I’m to the point in my build where I need to obtain a drive train. I’d like to use a 6.0 L and 6L90. Is the 6L90 TCM compatible with a LY6 or do I have to go with the L96

[Jackson's Dad 64 C10]

I'm not the expert here by any stretch of the imagination, but I picked up a complete take out from a 2011 Silverado 2500 last year. It is an LY6 with a 6L90 as the factory drivetrain. I have the computer, harness, etc. Since they were a factory combo, I would think that you can find one. I'm not sure what other transmission options backed the LY6, but I'd probably try to find a matched set. That way the computer is already ready to go. I'm sure that some others with more in depth knowledge will chime in soon.

Good luck!

Chris

[Madkidd007]

The only issue that you can’t get around is your crankshaft. You have to use a 58x relcutor, a 24x is not compatible with any of the controllers for a 6 speed

[Jackson's Dad 64 C10]

Reluctor wheel shouldn’t be an issue when using the factory PCM/ECU/Whatever GM called the computer that year, as long as you’re using a factory engine trans combo... It would be an issue with a standalone aftermarket controller, i.e. if you wanted to carb the engine.

[Madkidd007]

Originally Posted by Jackson's Dad 64 C10

Reluctor wheel shouldn’t be an issue when using the factory PCM/ECU/Whatever GM called the computer that year, as long as you’re using a factory engine trans combo... It would be an issue with a standalone aftermarket controller, i.e. if you wanted to carb the engine.

Actually it’s an issue with any combo using a 6 speed auto. No matter what combination, matching or not. The 6L trans series requires a 58x relcutor. Hence the reason you can’t swap an 06 tbss LS2 with a 6 speed but 07 and up you can. To directly answer the original posters question as long as you get a true gen 4 motor with a 58x relcutor you’re good to go. I say true gen 4 because in 06 LY6 engines were still using a 24x crank with everything else being gen4. Example my 06 5.3 LY6 24x had DOD using an E40(LS2) ecm and T42 trans module.
Tbssowners.com is a good place to research this as 07-09 owners have been known to upgrade from the 4L70E that I’m unfortunately stuck with.

[Jason 56]

Originally Posted by Madkidd007

Actually it’s an issue with any combo using a 6 speed auto. No matter what combination, matching or not. The 6L trans series requires a 58x relcutor. Hence the reason you can’t swap an 06 tbss LS2 with a 6 speed but 07 and up you can. To directly answer the original posters question as long as you get a true gen 4 motor with a 58x relcutor you’re good to go. I say true gen 4 because in 06 LY6 engines were still using a 24x crank with everything else being gen4. Example my 06 5.3 LY6 24x had DOD using an E40(LS2) ecm and T42 trans module.
Tbssowners.com is a good place to research this as 07-09 owners have been known to upgrade from the 4L70E that I’m unfortunately stuck with.

Thanks, this is what I thought. I was planning on finding a Gen IV engine which I can source locally. The trans I’ll have to find on eBay. I live way up north near Lake Superior n to find a 2wd up here is rare. Everything is 4wd

[Madkidd007]

Originally Posted by Jason 56

Thanks, this is what I thought. I was planning on finding a Gen IV engine which I can source locally. The trans I’ll have to find on eBay. I live way up north near Lake Superior n to find a 2wd up here is rare. Everything is 4wd

Don’t rule out a 4WD yet. Do your research on the speedometer issue because if you have to use something from advance adapter that requires an output shaft swap then a full dissemble with happen anyways.

Originally Posted by Jason 56

Am I correct that the ECM will just have to be reprogrammed so it recognizes the 6L90

This will all just depend on the donor engine harness, but either way it’s doable

[Jason 56]

Am I correct that the ECM will just have to be reprogrammed so it recognizes the 6L90

[AMERICAN PICK-UP]

Originally Posted by Jason 56

I’m to the point in my build where I need to obtain a drive train. I’d like to use a 6.0 L and 6L90. Is the 6L90 TCM compatible with a LY6 or do I have to go with the L96

Find you a late model chevy 2500 express van complete matched pullout.... they are most all 2wd and 6.0 L96 mated to a 6l90e..... i have sold 3 of them already this year. i just sold a 2018 model with 20k miles.... they are out there...

[rowdy11]

If you plan to keep the original transfer case, you will have to install an adapter from your NP205 to 6L90. Worth it IMO to avoid having to go drivers side Tcase drop and change out your front axle.