[Lawrence]

I am looking to do a powertrain swap and before I start thinking about which package to use, I need some info on the transmission. One of the mods I’ll be doing will be to incorporate paddle shifters to “manually” shift through the gears if wanted. For that, I was looking at the 6L80 tansmission, as I would prefer to have 6 speeds. However I do not know if it will fit in my project, but I know the 4L60 will fit without any problems.

Does anyone have the dimensions or the physical differences between the 2 transmissions? I seem to be getting conflicting information, as some tell me one is much larger than the other, while others say they are about the same size.

One gentleman told me that the 4L60 has a circumference of 55” and is 18” tall and that the 6L80 is 50” around and 18” tall. The main difference being the output shaft is located higher on the 6L80.

Any information is greatly appreciated.

 

[Triple-X08]

if your worried about the output shaft being at a different height, i wouldnt worry about it, its more so your drive shaft pitch. as long as you stay at about 4-6 degrees max you wont have any problems. check it with a 4l60 and compare it to a 6l80, if they are the same or about a degree difference then its cool. another deal is slip yoke and drive line length. if you need to have a custom driveshaft made for it then it will require you to check driveline angles.

the manual shifting with the paddle shifters wont be too difficult. a 6l80 should already have a TCM that incorporates this in it, like as in a 2500 HD with a 6.0 in it for ex. except a 2500 HD uses the manual selectable buttons on the shift lever itself. but shouldnt be any different, just depends on how its wired, whether it be done by a variable resistance, like a steering wheel control, or by a switch, to just tell it to switch gears up or down. all can be incorporated, just need a wiring schematic from a 2500 HD with a 6l80 in it, and you can look at the shift control for the truck, and basically substitute the paddle shifters in place of the gear selector handle.

what are you building.

also another thing to take in consideration, is the fact of length on the 2 trans. and your mounting may be different on one than another, as far as a cross member, or bell housing. torque converter size and lock up all need to be considered.

but if you just going to run paddle shifters with a actuator to change gears than it throws out the whole TCM deal.

that shouldnt be too difficult either, they make a kit for this, i know someone does, be it B&M or TCI. or whoever. they make a paddle shifter kit for auto trans.

i wouldnt think over all diameter wouldnt make a difference, especially if the 6l80 is smaller in diameter, it would make it easier to work with than the 4l60 because it is smaller in diameter, which means you can work around it easier and fit more stuff in there if needed.

any other questions please ask.


it would help greatly to know exactly what your planning on building, then i can be more helpful to give you ideas.

 

[Lawrence]

Triple-X08,

Thank you so much for your response. Here is what I am doing.

I have a heavily modified 2004 Wrangler that I use on the weekend to go wheeling and rockcrawling with my family. Although it serves its purpose, I have never been a big fan of its powertrain, or all Mopar ones for that matter, so I am looking to swap in a GM powertrain. It would also help when pulling our camper.

Many people have done swaps before, but nobody I know has done a California legal swap. Many say it is impossible to pull off, however, I have talked to a referee for the past 4 months about the legalities and he is willing to work with me through this project.

The goal is to find an extremely low mileage powertrain, and to work with the referee and document everything on various forums, in order to show that it can legally be done. That way, there may be a few more converts to the GM side.

Those who have done these swaps have mostly used a Gen III engine and a 4L60 transmission, and they haven’t hooked up the emissions stuff. I have to use a 2004+ engine (passenger car or truck), and I plan on using an aluminum block, so the possibilities are LS1, LS2, LS3, L76, L98, LM4, L33, LH6, and L92 (nothing you guys already don't know ). I left out the LC9 since I am not sure if the Flex Fuel option would give me problems.

I would much rather go for an LS series for various reasons, but the cost seems prohibitive compared to the Vortec engines. So, one of the possibilities I have been pondering is the L92/6L80 combo, but I don’t know about the physical size (length/width/height) compared to a 4L60.

I have already talked to a few folks to understand some of the “challenges” of that project. For instance, GTO manifolds seem to work best to clear the frame rails and to avoid firewall modifications, a rear sump oil pan has to be used to clear the front axle, the AC compressor has to be relocated to avoid notching the frame, etc…

However, I plan on doing a few tricks ideas. I have talked to several companies and I have received some positive feedback so far.

Now, about the paddle shifters. When I bought the Jeep, my wife told me to make sure she could drive it, so that pretty much ruled out stick shifts. So, the thing I have in mind is a “Tiptronic” like transmission. Stick it in Drive and it acts like a regular automatic (no activation of the paddles to prevent accidental use), but flip the shifter (or a switch) and the paddle shifters are activated.

I know TCI and Twist Machine have paddle setups, but they are not compatible with airbag equipped steering wheels. So, I did a bit of research and came across a Lincoln LS forum where the guys are using BMW SMG paddles(http://www.lincolnvscadillac.com/tech/Lincoln-LS/paddle_shifts/ ). That’s the way I’d like to have it.

Another thing I'd like to do is to use the GTO instrument cluster. Is it possible to use it with any donor powertrain (read ECM) from the GM family?

BTW, I have kept an eye on ebay and car-part, but are there any other sources for a complete powertrain?

 

[Slideways]

Many people have done swaps before, but nobody I know has done a California legal swap. Many say it is impossible to pull off, however, I have talked to a referee for the past 4 months about the legalities and he is willing to work with me through this project.

That's awesome! I get tired of a lot of people's defeatist additude when it comes to smog-legal swaps. They can be done, and it looks like you've done your homework. Sorry I can't be of much help, all I know is that the 6l80 is a great transmission from my experience in Denalis and Escalades. Good luck, and keep us posted!

 

[Triple-X08]

get rid of the stock steering wheel setup, you dont need air bags.

if you want to run a automatic that drives like an auto, my idea would work, just need a pcm or a tcm from a 07+ 2500 HD and instead of the normal column shifter controlled selectable up/down shift buttons use a paddle shifter setup from like a malibu or something like that, or even from tci.


your felx fuel idea is definitely viable. just need to run stainless piping or whatever is minimum recommended for E85 fuel to run on, and you need an engine that can run on it, like a 5.3 or whatever. not sure if the internals of a normal engine will handle E85 or not, have to check on that, but the only thing you need is a ECM from a vehicle with E85 and have the sensor that checks the fuel alchohol content level.

so if you can find a powertrain from a 08 2500HD with a 6.0 or 6.2 and then run a 6L80 in it which it is equipped with, and get the wiring harness and the trans and engine controllers from it, you will be all good. and basically in place of the stock steering wheel you put in a grant steering wheel or whatever, and you get a TCI paddle shifter or a paddle shifter setup from a doner car, which it will take place of the gear selector setup on the 2500 HD, because like i said they have selectable gear, like a tap shifter, just its mounted in the shifter lever itself.

not too hard it sounds. just alot of work if you plan on running all the extra stuff.

the main thing is you driveline angle, that will tell you if you can run a 4l60 or 6l80 in it. thats the main thing i would be concerned about. the other stuff is just wiring and mounting. if your driveline angles arent right, then its going to be tricky. especially if your doing it to a wrangler. if the output shaft is higher on the 6l80 then it may pose a problem, in place of say a 4l60. another problem is the transfer case. then you will definitely need to come up with some ideas. because thats a whole new challenge in its own.

 

[Lawrence]

get rid of the stock steering wheel setup, you dont need air bags.

I do need airbags as I run this vehicle on the street. I don't plan on taking them off.

if you want to run a automatic that drives like an auto, my idea would work, just need a pcm or a tcm from a 07+ 2500 HD and instead of the normal column shifter controlled selectable up/down shift buttons use a paddle shifter setup from like a malibu or something like that, or even from tci.

Good idea, but paddle shifter from a Malibu? I have to look into this one, I didn't know they came with this option.

your felx fuel idea is definitely viable.

No, I meant that I don't know if a Flex Fuel engine will give me more trouble hooking up as far as parts and reprogramming. Thruthfully, I don't care too much about it as I have yet to see E85 being sold around Los Angeles. If the LC9 is the same as the others for the swap, then I might consider it.

so if you can find a powertrain from a 08 2500HD with a 6.0 or 6.2 and then run a 6L80. not too hard it sounds. just alot of work if you plan on running all the extra stuff.

Yep but that doesn't scare me.

the main thing is you driveline angle, that will tell you if you can run a 4l60 or 6l80 in it.

Yes, I already run a slip yoke eliminator and a CV driveshaft b/c of the short shaft and the lift. The thing I have to figure out is if the 6L80 will raise the angle, and if so I'll probably stick with the 4L60. Transfer case is no problem, there are adapters available.

 

[Lawrence]

That's awesome! I get tired of a lot of people's defeatist additude when it comes to smog-legal swaps. They can be done, and it looks like you've done your homework. Sorry I can't be of much help, all I know is that the 6l80 is a great transmission from my experience in Denalis and Escalades. Good luck, and keep us posted!

When I first thought about doing this, everyone told me it is impossible to pull off, and that I’d be better off to do it and “pay” someone every time I need a smog certificate. The main reason for their comments is that they do not understand the rules, or they do not care about them. Then, the same people cry foul when they fail a smog test and get sent home packing.

I always like a challenge, so I did some research and I talked to several referees (you have to go through them to get your vehicle inspected and tested) until I found one who understood the scope of the project and who is willing to work with me. His enthusiasm has been great and he even gave me his direct number (to bypass the DMV) in case I have questions in the middle of the swap.

I wouldn’t even entertain the idea if I couldn’t do it legally, but it doesn't seem that hard and I can’t wait to tie some of the loose ends so that I can start this project.

 

[Triple-X08]

well, sounds like it would be a great idea to do it, im sure it isnt cheap. but if money isnt a problem then your ok.

definitely a neat project. and i cant say i have ever heard of anyone doing a swap to this degree.

i would be more than happy to help with anything as far as explaining something or helping you with an idea, or if i can give any kind of advice. i am always willing to help people and i will help you the best i can.

there are alot of people on here that have a good backing of knowledge, and technical background. as im sure there are alot of other places that can assist you as well.

anyways, keep on track with it, and keep me updated on the progress.

 

[Prohobby]

I purchased a 2007 L92 6.2L motor with the engine harness and computer. I then purchased a 2008 6L80 tranny without the harness. I'm installing this combo in my 1957 Chevy pickup truck. Please help me get this thing up and running. I'm open to any/all sugestions. Thank you.

 

[chakis24]

i was watching one of those truck shows on spike, they did a hemi swap into a wrangler, and they made it absolutely clear that for it to be legal the new powertrain has to be from the same manufacturer of the original- no matter what came out the tailpipe. id check into that if you havent already.