6L80E questions

[olblue81]

I just picked up a 17,000 mile 6L80E from my insurance company out of a 2007 2wd Sierra. It's going into my 1981 GMC someday but I've got some questions that so far I haven't found answers on here for.

1. What yoke does the trans need? I'm unsure what yoke I'll need to run and the trans didn't come with one. I'm supposing my best bet is to order one from GM for the truck the trans came from and have a new driveshaft built with 3/4 ton u-joints. But if I do that, how am I going to mate it to the 12 bolt rear?

2. I picked up an ECM (PCM) from them as well. They said that it mounted near the battery on the donor truck. But I've read on the net that the ECM is internal in the trans. Anyone confirm that there should be an external or internal ECM?

Thanks.

[olblue81]

Ummm, I'm not sure I have a 6L80E like I was told. I was looking on gmpartsdirect for a yoke and it shows a 6L90E for the application. I'm going to have to measure the length of the tranny to find out which one I have now.

[usmcchevy]

The Transmission Control Module (TCM) is in the pan of the trans. No one makes a stand alone controller for them yet so you need a 08+ 58x crank LS style engine to run it. This is pretty much all I know about them, hope it helps a bit.

[olblue81]

Originally Posted by usmcchevy

The Transmission Control Module (TCM) is in the pan of the trans. No one makes a stand alone controller for them yet so you need a 08+ 58x crank LS style engine to run it.

I wonder what module they sold me at the insurance co?

I'm looking for 08 up motor. I've been told the new body style 07 trucks had the 58x crank sensor. This tranny is from an 07 so that makes sense.

[usmcchevy]

Originally Posted by olblue81

I wonder what module they sold me at the insurance co?

I'm looking for 08 up motor. I've been told the new body style 07 trucks had the 58x crank sensor. This tranny is from an 07 so that makes sense.

07 being the change year I thing you have a chance of ether Mine is a 07 (van) and is a 24x.

[olblue81]

Originally Posted by usmcchevy

07 being the change year I thing you have a chance of ether Mine is a 07 (van) and is a 24x.

I've been told it has to be an 07 new body style (GMT900). Is that what yours came from? Or was it the 07 Classic style?

[Clyde65]

Vans and trucks are different as far as the motors, the older motors seem to had been used in the vans more. like in 03, trucks and SUV's went to the DBW throttle body, the Vans were DBC for another 2 years, so that pattern seems to continue as far as the reluctor. I am no expert just spewing what I have read.

[usmcchevy]

Vans didn't get the 58x until 08, I was just making sure you knew they used both in 07. You're on the right track.

[usmcchevy]

found some info here: http://ls1tech.com/forums/conversion...does-go-2.html

[olblue81]

Originally Posted by usmcchevy

found some info here: http://ls1tech.com/forums/conversion...does-go-2.html

thanks!

[Mr. 250r]

Well 3/4 u-joints could possibly be 1410.... which are quite a good size my new 2005 FF axle came from a 3/4 and has a 1410 u joint so i need new driveshafts because they do not make a jump joint from my old one to a 1410 as far as mating it to the 12 bolt rear end i couldn't find a 1410 style yoke for that diff so you could try a 1310/1350/1410 depends on what your tranny yoke is

[olblue81]

Originally Posted by Mr. 250r

Well 3/4 u-joints could possibly be 1410.... which are quite a good size my new 2005 FF axle came from a 3/4 and has a 1410 u joint so i need new driveshafts because they do not make a jump joint from my old one to a 1410 as far as mating it to the 12 bolt rear end i couldn't find a 1410 style yoke for that diff so you could try a 1310/1350/1410 depends on what your tranny yoke is

Thanks for the info. I did a quick google a week or so ago and found that there is a 1350 yoke available for the 12 bolt. Still unsure what the tranny yoke will be.

[Mr. 250r]

if you read this build http://ls1tech.com/forums/conversion...ng-hauler.html look for post #8 it says the 6l80/90 uses a 1410 so the way i understand it is he did have one built with a 1410 on one end and a 1350 on the other which is an option you could try which shouldn't be a big deal for a drive shaft maker

[olblue81]

Originally Posted by Mr. 250r

if you read this build http://ls1tech.com/forums/conversion...ng-hauler.html look for post #8 it says the 6l80/90 uses a 1410 so the way i understand it is he did have one built with a 1410 on one end and a 1350 on the other which is an option you could try which shouldn't be a big deal for a drive shaft maker

Thanks for the link!

[effects66]

Originally Posted by usmcchevy

The Transmission Control Module (TCM) is in the pan of the trans. No one makes a stand alone controller for them yet so you need a 08+ 58x crank LS style engine to run it. This is pretty much all I know about them, hope it helps a bit.

Actually they do make a stand alone controller for all GM trannys, including the 6l80e. TCI makes it.

[usmcchevy]

Originally Posted by effects66

Actually they do make a stand alone controller for all GM trannys, including the 6l80e. TCI makes it.

http://www.tciauto.com/tc/tcir-ez-tcutm.html

"TCI EZ-TCU-Compatible with most popular GM transmissions, including the 4L60E, 4L65E, 4L70E, 4L80Eand 4L85E, as well as the TCI® 6x Six-Speed Transmission"

The TCI 6x is a 4l80e with two more gears, not a 6l80e unfortunately.

http://www.tciauto.com/tc/transmissi...-1.html?main=4

[olblue81]

My plans are for a Speartech harness and PCMs. Not the cheapest out there, but it's complete and easy. Honestly, I'm pretty sure he just buys it from GMPerformance Parts and tunes it, but that's fine with me.

So now I'm just hunting for an engine. Once I have those, then finding accessory drive, headers and the small stuff will start.

[clinebarger]

Originally Posted by olblue81

My plans are for a Speartech harness and PCMs. Not the cheapest out there, but it's complete and easy. Honestly, I'm pretty sure he just buys it from GMPerformance Parts and tunes it, but that's fine with me.

So now I'm just hunting for an engine. Once I have those, then finding accessory drive, headers and the small stuff will start.

Slow down killer, If you already have a E38 ECM (1st pic), And remove the TCM/Control Valve assembly. You can send both modules to Speartech for reprogramming. NO need to buy new.

I would like to idenify the ECM you have, The second pic is a E40 ECM..Later E67 ECMs look similar...3 plugs. The E38 ECM you need has 2 plugs.

If you need help removing/installing the TCM let me know.

[olblue81]

I'll upload a pic of it later today.

[olblue81]

Originally Posted by olblue81

I'll upload a pic of it later today.

This is the module that I have. Called a Transmission Module on the tag on it. The number on it is their stock number. I don't have an engine PCM yet.

I see on the Speartech site that they have this module as part of their kit. So I might return it to the salvage yard. But for $80, I just might keep it too.

[clinebarger]

Originally Posted by olblue81

This is the module that I have. Called a Transmission Module on the tag on it. The number on it is their stock number. I don't have an engine PCM yet.

I see on the Speartech site that they have this module as part of their kit. So I might return it to the salvage yard. But for $80, I just might keep it too.

That is a TCM for a 4 speed auto.......4L60E/4L65E/4L70E/4L80E/4L85E.

The TCM/Contol Valve Assembly Is bolted to the Main valve body INSIDE the transmission on ALL 6 speed 6L80E/6L90E autos. Its not hard to remove with the right tools & keep everything clean.

I would return the TCM, It does no good on a 6 speed.

[olblue81]

Originally Posted by clinebarger

That is a TCM for a 4 speed auto.......4L60E/4L65E/4L70E/4L80E/4L85E.

The TCM/Contol Valve Assembly Is bolted to the Main valve body INSIDE the transmission on ALL 6 speed 6L80E/6L90E autos. Its not hard to remove with the right tools & keep everything clean.

I would return the TCM, It does no good on a 6 speed.

Thanks for that.

I noticed on the Speartech site that there is an image shown for their 58x harness for 4L60E/4L70E/4L80E/6L80/6L90 trans that has this module in it. But I suppose that could be because the image might be of a 4L80E harness. I would post it here but unfortunately his site is flash and I can't copy it.

I haven't contacted Speartech yet since I was worried about finding an engine before finding a harness.