BIGDADDY1969

So i've had the misfortune of acquiring a 2010 6L80E with the new TCM that will not communicate with my 08 ECM AFTER VIN flash at dealer. i have a thread in reference to going to tuner after 6L80E swap with details. There are 2010 6l80Es out there that have the older TCM that will work with the 08 ECM And communicate after VIN flash ... however my question is what will be the issues with changing my ECM to the correct one(2010) for the TCM to communicate? Not guesses please. What will happen and wont happen? Thanks . Just trying to see what s the best option. i was looking at buying the TCM and changing it but it would require changing valve body and all by looking at GM diagrams of the 6L80E for the two yrs 08 and 2010. thats just as expensive as buying another trans... so back to my question what is the issues with using the 2010 ECM for with a 2010 5.3 6L80E program flash in my 08.... I didnt search yet if theres an LY5 5.3 for that yr..my 08 is a LY5 5.3

BIGDADDY1969

A VIN number for a 2010 Silvy or sierra with a LY5 would probably get me what i need, ... i see a list where LY5s were in 2010s but i would need a VIN to verify ... thanks

BIGDADDY1969

another question ... was there a 5.3 in 2010 thats non-flex fuel?

01WS6/tamu

iTrader: (36)

I would just get a svc number for pcm for a 08 6.2 6L80 denali. Put pcm flashed for 08 denali in your truck and then have whoever is doing all of the tuning just tune the motor as necessary to run on the denali calibrations. DOD will go away but DOD sucks anyway so it's no loss. But if you want a 2010 pcm then follow below

Install 2010 pcm for a 6L80E 5.3 combo into your truck and flash to 2010 VIN for both modules. TCM is internal to the 6L80 6speed.

Repin the harness as necessary to match your 08 I'm sure there will be something that will need to be moved I have not looked at diagrams side by side to see what needs to be moved.

At that point it will shift and work correctly. If you want the tapshift to work you will need to change the shift lever and may or may not have to run wires to the bcm depending on if your truck has them already installed. The BCM will need to be replaced to a Uplevel BCM for a 08 you would order it for a denali truck. Then flash the bcm and radio and if you have xm and rear object detection those modules will have to be replaced with brand new never unprogrammed modules because they are VIN locked and will cease to function once the VIN in the BCM no longer match's And you also need to change to a 6 speed IP cluster and flash for VIN of Bcm

BIGDADDY1969

Ive done the 08 denali flash ... The problem is that the tcm wouldnt accept it all the waythrough and close but iamkeniffs 2010 6L80E worked with just the vin flash by the same dealer and tech so this led the tech to now believe the tcms are different which i know after. I researched more that there is 2 different ECMs as i had previuos mentioned (If i hadnt gotten in detail here its because i had already posted it all on my other thread 'finally going to tuner after 6L80E swap') ... However i am yet to find out if there are 2 different ECMs for 2010 to mate with the corresponding 2 different TCM s in the trans. The vin flash and retune after i understand and have down pact lol ... Im trying figure if theres 2 ECMS ... I have one availble a member on here is offering to sell an ECM from a 2010, its an E38 , so i can try an see if it will work .. If i dont find anything else on the ECMs in the 2010s im gong to go ahead and do it ..

01WS6/tamu

iTrader: (36)

What exactly did the tcm do when you tried to flash it to 08 denali. Was the pcm flashed for 08 denali before trying to flash tranny.?

Prior to this did you see if the svc number between 08 5.3 and 08 6L80 denali are same svc#

BIGDADDY1969

When he flashed it .. It was downloading properly and when it got to the end of the program it would start over .. It did this several times in a row and wouldnt stop .. And yes i had flashed it once before but had a bad 6L80E.. This one now is a replacement for it from 2010 Silvy .. I brought it to dealer after swapping good tranny and that above cycle is what hapoened .. This the same tech that did iamkeniffs denali flash so hes up to speed on everything .. If by svc u mean the OS(Operating System) and ECM ? Yes i have the same ECM in my 08 for 5.3 that the denali 6l80e came with ... they both came with the same EcM i checked

01WS6/tamu

iTrader: (36)

TCM is different from 08 to a 10' model svc numbers are different. Find a vin for a 10 5.3/6L80 truck and flash it that vin. Then you are going to have to go in with HP tuners and disable the passlock. The passlock passwords change from year to year and a 10 pcm and flash will not match 08 passwords from the bcm and cause a no start.

As far as swapping pcm's pull a pinout for both trucks and go location by location to verify if wires are in correct spot or need to be moved then move as necessary and you will be good to go.

BIGDADDY1969

The tech said he can flash the BCM also .. Think if he flashes it with 2010 vin along with ecm n tcm it will all match? He had actually done it with the 08 denali vin .. But u think the 2010 vin flash will work on the bcm as well? With me swapoing to a 2010 ECM to match the 2010 tranny is what im saying

BIGDADDY1969

And im gunna hafta look fir the diagrams of the 2 ECMs .. I hadnt ever looked at pin outs for them