E38 os swap for 6l80e/ larger injectors more maf range????

[lt1z350]

So I have a 2007 tahoe 4l60e and going to swap the os to run with the 6l80e and like to upgrade to the best os I can use on this thing. Going to a 850cc injector on it at same time and do know I have the limit on the 2007 os table where have to double the stoich to make it work. So if say a 2009 is known to work from a similar 5.3 tahoe as that runs the 6l80e software I need I will run that. I know lots here have most likely done it and wondering if my current e38 will take the newer os or I will need to update that too. I picked up a new 6.0/6l80e harness from the dealer for 138 bucks so couldn?t go wrong on that. Rather then going with a conversion harness as figured better to just go with new os that will run a larger injector better anyway. Also think the newer os will have more maf range too as if I?m on 2bar it?s ok but went back to normal vve to get my tune good for the swap and saw the maf is back down to 12,000 hz and now it?s about maxed out. So a 2008-2010 os swap will probably be a good upgrade all around I?m hoping anyway and why asking. Thanks for help

[Jon S.]

... I picked up a new 6.0/6l80e harness from the dealer for 138 bucks so couldn?t go wrong on that ...

Good chance that the wiring harness that you purchased is for a late model E78 & T43 combination.

The E78 ECM has 3 connectors, while your E38 ECM has only 2 connectors - you could repin the harness into a set of E38 connectors.

The MAF, MAP, Oil Pressure, and Starter connectors will also likely be different than was used on your 2007 model truck.

[lt1z350]

It’s got two it’s a part number that a few other swaps used from 2007-2007 Tahoe’s and trucks. Your right on the oil pressure sending unit they did say swap connector there. Just need to figure out my os. I think a 2009 had the better maf and injector tables just not sure if will work in my part number ecm. I may have to change to another e38.

[camaro1]

I tried an ecm swap similar to this and I could not get the speedometer to work,, I tried a bunch of different things in the tune,, everything else with the larger injectors worked out perfect and the trans would shift fine but no speedo,,, something had to be different about how the cluster decoded the serial data

[lt1z350]

I was going to do a bcm update too for the prndm to work right on the cluster as I have a gm mdi2 and tis access. So I guess if I have to for speedo then no biggie. Was it a truck or suv? Just curious what year you had and which os you went with? I have read about a bunch of guys doing this on performance trucks.net but really wanting the better os I figured I would ask here with so many more performance orientated projects rather then just truck builds. With the better trans I will be able to push the 5.3 to what it can make rather then low timing and short shifting to keep the duty cycle and power down. Some 85 lbs injectors e85 tune and shifting back at 6k vrs 5200 will wake this up pretty good and was already able to out run a new mustang 5.0 on a roll..... Its fun for a daily and just like to have it more capable.

[camaro1]

mine was on 07 new body Silverado MAX 6.0,, the only reason I tried was to make tuning the large injectors easier, and I had spare ecm's, and gm mdi and tis, I tried several different newer truck files, all of them worked fine for tuning and ran and shifted fine,, just no speedo

[lt1z350]

So my 07 tahoe very similar I assume and same here have all the GM stuff to play with factory os. I might just try a 2009 tahoe 5.3 with the 6l80e and hope it doesn’t bbq my ecm. I don’t know if true but read some say you can brick the ecm with the wrong os. I can’t want I have read good things on the extra two gears for both mpg and how it pulls as no drastic drop on the shifts plus it has less drivetrain loss as more efficient transmission.

[castorjames]

So my 07 tahoe very similar I assume and same here have all the GM stuff to play with factory os. I might just try a 2009 tahoe 5.3 with the 6l80e and hope it doesn’t bbq my ecm. I don’t know if true but read some say you can brick the ecm with the wrong os. I can’t want I have read good things on the extra two gears for both mpg and how it pulls as no drastic drop on the shifts plus it has less drivetrain loss as more efficient transmission.

i dont recommend flashing 2009 calibration into a 2007 pcm, i have try it without succes, i dont like 07 PCM?s

[lt1z350]

i dont recommend flashing 2009 calibration into a 2007 pcm, i have try it without succes, i dont like 07 PCM?s

so should I get a 2009 ecm? thats what I have been trying to figure out. I saw a guy did this on a 2007 gmc and said used the 2009 os in it. I think a 2008 tahoe had the 6l80e but it was with the 6.2 and sort of a one off during that time frame a rare truck. I have to change it all up for the blower anyway so the 6.2 part shouldnt matter if that os might be better. That or just buy the part number for the 2009 ecm and flash it as that is a 5.3 and 6l80e. I guess I should go to the repository and look at tunes for those years.

[castorjames]

what year is your 6l80e? if it is <2011 test if it talks to the tcm, as soon as you shift to Drive or Reverse youll know if it is talking or not, if it is it will shift smoth into drive and reverse, if it bangs it is not talking, i think you will be ok with stock pcm, you can install 2009 ecm but may have problems with fuel gauge readings and other stuff, can be done, you just need to do some tests and be patient

[lt1z350]

I purposely got the 2007 so the tcm would be the correct on for the application if it all came that way. Hoping that it would make all of this easier. I tested my techem on a trans at work and on the dyno it shifts good so know all that is good and hoping I dont even have to flash it but just do the ecm side of it to get it up and going then use hptuners to tweak it all out. If the fuel gauge was off couldnt I just use the settings from my 2007 one? I might just flash up the stock pcm with a 2008 pick up that has a 5.3 and see how it goes I have 2 ecms so if I do fry one and might buy a good used 2009 part number to try using that too and just stick with what works best. All the wire harness pins are identical from 2007-2009. All the stuff that goes into the 4l60e tcm is exactly the same it just goes to the 6l80e as I printed out all the harness info from my 2007 to a 2009 truck with a 4.8/5.3/6.0/6.2 They all use the exact pin out motor doesnt matter so all changes are in the ecm which if you get the combo correct then should work out fine. I dont even wonder if the os thats in the truck now might run the 6l80e as all the trans data is in the tcm other then gear ratios but now saying that I think they only give you 5 to change on the current os so it will probably be a gear short and act as a 5 speed if try to use the same os in it. Much of this is the same and gm did a good job on not changing up much to make this new trans work and most likely to be cost effective. Im up for all comments and ideas and once I work this all out I will make sure its updated here as I hate dead threads more then anything when doing a search. Thank you for answers and ideas so far!!!

[lt1z350]

so my 2007 tahoe file and a 2009 tahoe whipple file I pulled. Its a 6.2 but has 127 lbs/hr incjector data and maf is a single table to 15,000 hz so better then my current to 12,000 hz as im up on it on this maf size. The 2009 also has all the 6 speed data on it but possibly a 5.3 truck might be the better way to go as long as injectors are the same and maf and not the same limits as my 2007.

[lt1z350]

So got this thing done and just so others know the current os in the e38 in 2007 will automatically see the new t42 tcm and swap the back side of tabs the speedo>calibration for the 6l80e. So if you buy the same year trans as your truck it’s all plug and play. I put the 2007 tcm (which is also a 2008 tcm os so could use either ) into my 2007 Chevy Tahoe and didn’t change or write anything and the trans worked as you would expect it to as stock. I did swap to a new tcm due to the other was pretty old and who knows how many miles as the trans I got was toast and had to build it. So for now to match my 2007 os I wrote the 2008 tcm os back into it and did some tweaks in my tune and it works great. This is the best swap for these drives so much better then 4 speed.
I do want to change over my spare e38 to a 2009 os to still get the 127 lbs injectors and the extended maf table but not going to write over this other that I know works as of yet. I can easily write the tcm to a 2009 to match the 2009 engine os just have to figure out if my part number ecm will take the 2009 os. Once I do this I will update the thread for others. This is a great mod and fairly easy if you buy the correct years will not need GM access to write anything.

[castorjames]

good news it worked , but i have to say that some times even same years are used it doesnt work, always best to use matched PCM/TCM VINS calibrations, have succesfully done it same way but in some aplications it didnt.

[jjs]

So got this thing done and just so others know the current os in the e38 in 2007 will automatically see the new t42 tcm and swap the back side of tabs the speedo>calibration for the 6l80e. So if you buy the same year trans as your truck it?s all plug and play. I put the 2007 tcm (which is also a 2008 tcm os so could use either ) into my 2007 Chevy Tahoe and didn?t change or write anything and the trans worked as you would expect it to as stock. I did swap to a new tcm due to the other was pretty old and who knows how many miles as the trans I got was toast and had to build it. So for now to match my 2007 os I wrote the 2008 tcm os back into it and did some tweaks in my tune and it works great. This is the best swap for these drives so much better then 4 speed.
I do want to change over my spare e38 to a 2009 os to still get the 127 lbs injectors and the extended maf table but not going to write over this other that I know works as of yet. I can easily write the tcm to a 2009 to match the 2009 engine os just have to figure out if my part number ecm will take the 2009 os. Once I do this I will update the thread for others. This is a great mod and fairly easy if you buy the correct years will not need GM access to write anything.

Interested in this conversion. What did the tranny come out of/where did you source it?

[lt1z350]

Interested in this conversion. What did the tranny come out of/where did you source it?

looking at your sig it will be a sweet swap. The trans was from a core place I deal with as I was going to build it so didnt care if worked or not. Ebay has a ton of them reasonably priced for ones that they say work. I did some mild upgrades to mine raybestos red clutches kolene steels and some sonnax parts a 456 drum kit the billet piston for the reverse 3-5 drum and did some valve body upgrades with a dual clutch ctsv zl1 2000-2400 stall stock converter. its strong and has a decent stall im seeing 1800-2000 with out trying hard. Probably will flash 2400 or so. Im not sure exactly what it came out of but the code on the trans was for my application 07-08 tcm and valve body. Most likely it was a escalade or denail with a 6.2 in it. When I rewrote my new tcm I used a 2008 yukon as it was the same operating system by code to the old one that was laready working with my stock os. You can find that info in the editor with the tune open under the edit tab calibration at the top.

[jjs]

looking at your sig it will be a sweet swap. The trans was from a core place I deal with as I was going to build it so didnt care if worked or not. Ebay has a ton of them reasonably priced for ones that they say work. I did some mild upgrades to mine raybestos red clutches kolene steels and some sonnax parts a 456 drum kit the billet piston for the reverse 3-5 drum and did some valve body upgrades with a dual clutch ctsv zl1 2000-2400 stall stock converter. its strong and has a decent stall im seeing 1800-2000 with out trying hard. Probably will flash 2400 or so. Im not sure exactly what it came out of but the code on the trans was for my application 07-08 tcm and valve body. Most likely it was a escalade or denail with a 6.2 in it. When I rewrote my new tcm I used a 2008 yukon as it was the same operating system by code to the old one that was laready working with my stock os. You can find that info in the editor with the tune open under the edit tab calibration at the top.

Thanks for the information lt1z350. I will look into gathering what I need to do the swap as my 4l70 has seen its better days.

[lt1z350]

If needing a built trans for the swap I have one ready to go been dynoed too so know it works good. I built a second one with all the updates as I had the parts to do it. The tcm is new will need a program or could stick a used one on it that has a os in it that’s not very old. That’s if your needing a trans for the swap. It’s for a 2007-2009 os if your truck is in that year range. I have 95 percent of the bigs figured out still playing with the tow haul and making the prnd321say prndm other then that this swap has been pretty easy. If need anything just pm me and can answer questions or tell you about this trans I have that’s ready to go.