6L80 auto trans in a H3/H3T?

[2010H3TAlpha]

I've been reading up on the 6L80 and its obvious strengths over our lowly 4L60's including performance, MPG, strength, etc. Also much more cost effective than the TCI 6X ($2k vs. $6k before labor). Downside is that the 6L80 requires a certain level of tuning to work correctly but I happen to be friends with the shop manager of a local performance outfit that specializes in, well, just about everything including deep knowledge of the GM world. Anyone else considered this swap or know if it has been done? I was going to register on 355 Nation to see what I can find over there as well but seems most people go to the T56 in that group and the 4WD guys stick with their 4 speeds. Will report back when I get time to ask around over there.

 

[06 H3]

Do you have the I5 or V8? Because the first gear is higher the the 4l60e and will make the I5 even slower off the line

 

[06 H3]

Other concerns are fitment and electronics.

Driveshaft mods and adapter plates are easy.

 

[2010H3TAlpha]

Do you have the I5 or V8? Because the first gear is higher the the 4l60e and will make the I5 even slower off the line

I have the Alpha so the 4.xx 1st gear would be awesome for crawling and launching off the line. The best thread I could find on 355 Nation were a bunch of I5 owners saying the same thing regarding worse performance and the conversation kind of ended there.

Other concerns are fitment and electronics.


Driveshaft mods and adapter plates are easy.

I am planning to stop by my brother's dealership tomorrow to compare PCMs, etc. for fun. He happens to be an electronics ninja so I will attempt to tap his brilliance. As for fitment, they both look to be the same size minus a possible "hump" on the 6L80 behind the bellhousing.

 

[f5moab]

6L80 requires a certain level of tuning to work correctly

Trying to understand this....Any transmission/engine combination requires a high level of tuning to make the two components work together. And during this so-called tuning process, there are hundreds of thousands of miles put on the combination to make all the qualities sync as good as possible.

I believe the 6L is larger, thus the fitment will require mods to the T/C mounting, shafts, etc., not hard to do with the correct equipment. I would guess the hardest part would be the tuning, but find a good tuner, pay him/her enough and anything can be matched.

If you are looking for strength, why not a raptor 4l60? Or if you want the extra gears and money is no object, why not a 6L90? The 90 series is mated to a Duramax under certain applications.

 

[RamRod]

So from my research the following would need to be done in order to run a 4L80 on an Alpha:

4" shorter rear driveshaft
4" longer front driveshaft
PATC wire harness conversion
New output shaft connecting to transfer case (PATC)
Move the transmission cross member back 4"
PATC engine to trans adapter plate

It is also possible that the transmission/driveshaft tunnel would have to be raised to maintain clearance


I might be missing a ring or two but the meat of it is there

 

[06 H3]

If you move the trans back 4in then the t case crossmember goes back and hopefully that means it doesn't hit the torsion bar crossmember.

 

[bebe]

You need to talk to Wayne Hartwig at Jeeperman, and Keith Beall at Susanville Transmission, and either Steve or Geno at Advanced Adapters. Anyone else is speculating.

This is not an easy adaptation, and aside from talking to the GM engineers who did the 6.2 L in an H3, they're just making educated guesses. (F5 excluded).

 

[SuperBuickGuy]

12k for a transmission (or more)? I'm not sure what you're going for, but those numbers are hard to justify (I briefly looked at doing this)

 

[2010H3TAlpha]

12k for a transmission (or more)? I'm not sure what you're going for, but those numbers are hard to justify (I briefly looked at doing this)

We were going to pick up the 6L80 for a little over $1k brand new but after talking to some more people tonight, this is not as easy as I had assumed

 

[06 H3]

While the 4l60e isnt as good as the 80e my personal issue with it is just heat and that has nothing to do with the transmission, its the cooling...but then again I am not running a V8, I am running the torque monster 5 banger :roll:

Why not go with the raptor kit? Granted there is no replacement for size, the 80e will always have bigger and stronger parts then then 60e due to shear size but the raptor depending on what level you get can handle over well over 500 hp.

I could of sworn the H3 with the atlas t case (on craigslist a month ago) had a 4l80e...but either way, time and money can solve just about any issue so I say go for it. You may fail or succeed but document it either way

 

[f5moab]

4L80 or 6L80?

If it was me (and it isn't) I would go with the raptor trans.

 

[atvspeed4]

Chris you are correct, it had a supercharged 6.0l, 4l80e, and an atlas. There was a thread on pirate that a guy bought it and was pulling stuff off it for his buggy...

 

[06 H3]

Damn. I wish I had some pictures...I know he doesn't have cupholders now lol. I wonder what lights he has ringing on the dashboard.

I'm gonna do the raptor kit...just waiting on my trans to explode. At 111k I'm guessing its sooner then later

 

[RamRod]

Damn. I wish I had some pictures...I know he doesn't have cupholders now lol. I wonder what lights he has ringing on the dashboard.

I'm gonna do the raptor kit...just waiting on my trans to explode. At 111k I'm guessing its sooner then later

That's exactly my thoughts, why waste so much time with trying to adapt everything when you can just bolt on a performer like the Raptor!

 

[High Five H2]

Hey, sorry this is a few days late, i saw this thread and I got excited because this was something that I've thought about, too. Now, I can't find any numbers about length and stuff but I think that the 4l60 is a bit longer than the 6l80. I would go with the 6l90 because its closer to the length of the 4l60 and its stronger, etc. there's a company that does makes a kit or does swaps, and they list the h3 as a candidate. I haven't looked into it much more than that:

http://www.tbmsport.com/6l80gm6spdinformation.html

With the lower first gear, you could go with bigger tires and still have stock gearing. Using the grimm jeeper site, I calculated that with a 6l90 you could use 35" tires and keep the factory 4.11s. Since making it work with the PCM is a problem, you could just mate it to the factory l92 and call it good. Just from looking at pictures on the GM media site the l92 and lh8 are identical on the outside.

Additional plus: use an H2 engine cover, and it still looks factory

I think this would be a fantastic project.

edit - i'm pretty sure this swap has been done to trailblazer SS's.

 

[High Five H2]

Oh yeah, another thing to think about is the output shaft. I don't know how many splines the 6l80 has, i think it's 32, and the 6l90 has 34 - i think. Don't know what to do with that. Also, since I believe the 6l trannies are shorter than the 4l, maybe use a spacer in between the transfer case and tranny? maybe?

 

[SuperBuickGuy]

$6,500 plus $1,000 for the computer - which has a custom tune and then fit it into your vehicle with drivesahfts... or replace the motor with an 08 or similar duramax or cummins... or spend 10k and buy a TDI Jetta for DD duties - then use your H3 for its intended purpose...

The 6L needs to get into the $2,500 range for a new one; then we'll talk - even so, I'm not certain that simply replacing the 5.3L with a new VVT 6.2L displacement on demand wouldn't net you far better mpg

sorry, I'm a skeptic...

 

[06 H3]

Any drivetrain swap will be expensive. JK hemi, LS, and diesel swap is over 20k with the trans.

So I'd expect trans swaps to be expensive. The real issue here isn't lack of power or a weak trans IMO it's the lax of being able to regear and put the trans and motor back to stock specs. Big tires add stress and a regear would help that but we can't regear easily

 

[Chocflip201]

More info/links on the "raptor" kit?

 

[CaseyS]

So from my research the following would need to be done in order to run a 4L80 on an Alpha:

4" shorter rear driveshaft
4" longer front driveshaft
PATC wire harness conversion
New output shaft connecting to transfer case (PATC)
Move the transmission cross member back 4"
PATC engine to trans adapter plate

It is also possible that the transmission/driveshaft tunnel would have to be raised to maintain clearance


I might be missing a ring or two but the meat of it is there

1) Take a look under your vehicle and make a note of where the transfer case would be if it were moved back 4". Correct answer is in the torsion bar cross member which is welded to the frame.

2) 4L80e bellhousing is standard SBC pattern, would need adapter and possibly new flywheel

3) Of course our transfer case is an oddball 5 bolt pattern. I haven't seen an adapter for this transfer case to 4L80e. Would require custom adapter fabricated.

Lots of things to be done to make this swap happen.

 

[SuperBuickGuy]

You need to talk to Wayne Hartwig at Jeeperman, and Keith Beall at Susanville Transmission, and either Steve or Geno at Advanced Adapters. Anyone else is speculating.

This is not an easy adaptation, and aside from talking to the GM engineers who did the 6.2 L in an H3, they're just making educated guesses. (F5 excluded).

I second this - talk to Wayne Hartwig; they're neat people - his partner (cohort?) is a GM tech that knows about everything there is to know about this platform

www.150Tunes.com
www.DiffsOnly.com
www.Jeeperman.com

 

[4speedfunk]

Jeez...Why? Of all the things to fiddle-fart around with on the H3...the transmission is one of the few parts that seems to be perfect for it.

(Hope I didn't just jinx myself) :whaa:

 

[mikola]

http://www.tbmsport.com/6l80gm6spdin...omponents.html

 

[Mb30sdl]

We'll driveshafts in my atlas swap in H2 are actually a blessing. Atlas Bering ~4" dhorter (at full drop rear driveshaft will hit TC crossmember) gave me an opportunity to make both driveshafts same length. But we fabricating removable crossmember at fronts of gas tank to mount rear driveshaft carrier bearing and with torsion bars removed it gives me FLAT UBP (mounted to frame) from beginning of the cab to almost end. Just by removing torsion bar set up I gained ~5" in break over angel.