Talk me out of a 6R80 automatic swap

Jezza

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I'm about to do an engine swap on the TJ to a 4.7l stroker and upgrading the turbocharger to a GT3582. The engine and turbo will be good for 5-600 hp give or take and the NV3550 that currently calls the trans tunnel home most likely will be overwhelmed along with the clutch. I have already ordered a Pro Series 4.3 Atlas that should start being built any day. The question I have is do I have it built for the 3550 knowing that I will probably change it out in the future, or do the auto swap now and have the Atlas setup for the auto and save having to do driveshafts and skid plate mods twice?? I think the Ford 6R80 is the trans I am most interested in running. It has a nice low 4:17 first gear and are known to hold huge hp stock. Guys are running these trans in Mustangs to over 1000 hp with little or no mods. Also Atlas has an option to setup the input for it as well, so with a phone call I should be able to get it done. The other huge benefit is the tuning. The AEM engine computer I am running would be able to handle the trans control and I could have options for convertor clutch lockup and paddle shift. Thoughts?? Pros - cons??
 
It's about the same physical size as the 42rle.

Downside you're making it more complex, but it sounds like you're already at that point regardless.
 
What’s it take to get the trans computer to work with the jeep motor? I assume the 6R80 is electronically controlled?
 
I'm about to do an engine swap on the TJ to a 4.7l stroker and upgrading the turbocharger to a GT3582. The engine and turbo will be good for 5-600 hp give or take and the NV3550 that currently calls the trans tunnel home most likely will be overwhelmed along with the clutch. I have already ordered a Pro Series 4.3 Atlas that should start being built any day. The question I have is do I have it built for the 3550 knowing that I will probably change it out in the future, or do the auto swap now and have the Atlas setup for the auto and save having to do driveshafts and skid plate mods twice?? I think the Ford 6R80 is the trans I am most interested in running. It has a nice low 4:17 first gear and are known to hold huge hp stock. Guys are running these trans in Mustangs to over 1000 hp with little or no mods. Also Atlas has an option to setup the input for it as well, so with a phone call I should be able to get it done. The other huge benefit is the tuning. The AEM engine computer I am running would be able to handle the trans control and I could have options for convertor clutch lockup and paddle shift. Thoughts?? Pros - cons??

Sounds Fun! , A couple of thoughts / questions, It seems to me alot of "newer" cars have an odd calibration that pulls power out of the engine during an upshift on the automatic. Does that have to be included to make the trans live?
How is the rest of the drivetrain set up for 500 -600 hp? , axles , drive shafts , and more important drive shaft U-joint angles ?
I get that a 600 hp. TJ is used differently than a 600 hp Mustang , more of a bang on it for 3 seconds vs. drag racing and track days.
But seriously how do you use triple the hp , I don't know how comfortable I would be at 150 mph in a TJ . But I'm probably just a pussy these days.

Sounds like a fun project , I love to see guys " hotrodding" just about anything !!! 😎
 
What’s it take to get the trans computer to work with the jeep motor? I assume the 6R80 is electronically controlled?

My stand alone computer I am running right now has automatic transmission controls, but I would have to set it up. Otherwise a box like this https://www.usshift.com/usq6.shtml will control all the electronics in the transmission.
 
My stand alone computer I am running right now has automatic transmission controls, but I would have to set it up. Otherwise a box like this https://www.usshift.com/usq6.shtml will control all the electronics in the transmission.

I don't know much about this side of things, but I always assumed the transmission needed info from the motor to run properly, but maybe not? I guess my question was around how do you integrate communication between the TJ PCM & the Ford TCM? Or maybe that's not even a thing, IDK.
 
I don't know much about this side of things, but I always assumed the transmission needed info from the motor to run properly, but maybe not? I guess my question was around how do you integrate communication between the TJ PCM & the Ford TCM? Or maybe that's not even a thing, IDK.

TPS and RPM are all that is required for that quick 6 controller. You can also add neutral safety, paddle shifting and transbrake if desired. The controller is programmable and has self learning options for shifts. They said it comes with pre-configured tunes for normal and aggressive driving. I also spoke with Atlas about the transfer case this morning and they informed me that the only change on their end is an input shaft and adapter plate that they sell. My only real hangup is going to be adapting the 4.0 to the 6R80 bellhousing.
 
Does advance not have an adapter for that? I think my next biggest fear would be how long is the trans + bellhousing adapter compared to the factory 3 speed? There is not much room for a longer drivetrain. Pinion angle is gonna be a thing I would expect.
 
Does advance not have an adapter for that? I think my next biggest fear would be how long is the trans + bellhousing adapter compared to the factory 3 speed? There is not much room for a longer drivetrain. Pinion angle is gonna be a thing I would expect.

No, they have an adapter from the 6R80 to their Atlas case, but nothing for the engine.

The 6R80 is 23.75 inches long vs my 3550 that is 23.1. I think the 32rh is around 24 as well. I'm not sure about the 42re. The block adapter should add less than 3/4". I should be alright if I keep it tight. The Atlas is shorter than stock as well.
 
My only questions are has it already been ran sucessfully by others that go crawling offroad? I'm curious about torque converter options/settings, how would it handle 1st to reverse shifts multiple times if you were stuck and needed to rock back and forth.. and how well does it handle extreme angles etc? Can you lock the converter up at idle if you wanted to? I'm just thinking that crawling has different requirements than desert blasting or drag racing.
 
My only questions are has it already been ran sucessfully by others that go crawling offroad? I'm curious about torque converter options/settings, how would it handle 1st to reverse shifts multiple times if you were stuck and needed to rock back and forth.. and how well does it handle extreme angles etc? Can you lock the converter up at idle if you wanted to? I'm just thinking that crawling has different requirements than desert blasting or drag racing.

I'm not aware of anyone running one in a TJ behind a 4.0. That is also evident in the fact that I cannot find an engine to trans adapter. It was the stock transmission for the Ford Raptor until 2016. I can't imagine that inclines and rocking it would damage anything especially in a light weight Wrangler. I'm not sure about locking up the converter. It's usually controlled by a solenoid in the trans. I'm not sure if you can lock it at idle, or why you would want to. Also crawling isn't an absolute requirement for me as I do it very infrequently, and any auto probably crawls better than the 3550.
 
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I'm not aware of anyone running one in a TJ behind a 4.0. That is also evident in the fact that I cannot find an engine to trans adapter. It was the stock transmission for the Ford Raptor until 2016. I can't imagine that inclines and rocking it would damage anything especially in a light weight Wrangler. I'm not sure about locking up the converter. It's usually controlled by a solenoid in the trans. I'm not sure if you can lock it at idle, or why you would want to. Also crawling isn't an absolute requirement for me as I do it very infrequently, and any auto probably crawls better than the 3550.

I wasn't thinking about mechanical damage, I was thinking about heat build up and torque converter slippage. If it's the trans from out of the Raptor then I would assume it's more suited for life offroad than average.
 
I wasn't thinking about mechanical damage, I was thinking about heat build up and torque converter slippage. If it's the trans from out of the Raptor then I would assume it's more suited for life offroad than average.

Ahh, I see. Obviously I would put a generous sized cooler on it to avoid heat being a major issue. The 6R80 was the all around transmission for Ford from 2011-2017 or so. Everything from F150s to Mustangs got them. Also because of that they are reasonably cheap. I could pick up 2 6R80s for the price of one used 3550.
 
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Ahh, I see. Obviously I would put a generous sized cooler on it to avoid heat being a major issue. The 6R80 was the all around transmission for Ford from 2011-2017 or so. Everything from F150s to Mustangs got them. Also because of that they are reasonably cheap. I could pick up 2 6R80s for the price of one used 3550.
Is that the same trans they use in the new Bronco?
 
Is that the same trans they use in the new Bronco?

Probably not, I think after 2017 everything got the 10 speed.

Edit... looks like a 7 speed is standard with the 10 speed being an upgrade on the better trim packages.
 
I seriously contemplated the 10L1000 Allison as I know how to control it. The problem is it was too damn big. Real big, and wide.
 
Other than the challenge of adapting to the 4.7 it should be a pretty good choice. They are an all clutch design and will take 1000hp with little work. Find the right converter and put an adequate cooler and you should be good to go.
 
Blaine was looking at swapping the nag1 jk transmission and I think it would be a cool phenomenal swap. I think the 6 speed ford would be even better. Both have aftermarket controllers. The physical bellhousing and torque converter and starter are not trivial because I don’t think anyone is offering a swap kit.
 
Other than the challenge of adapting to the 4.7 it should be a pretty good choice. They are an all clutch design and will take 1000hp with little work. Find the right converter and put an adequate cooler and you should be good to go.

I have the adapter covered.
 
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I picked up a used one a guy was selling local. It has a bad 3-4 shift but I got it cheap. It will allow me to start taking some measurements. Everything I found online has the NV-3550 at 23.1 inches long. I measured both of mine and they were both 24.5 inches long from bellhousing to the flange where the transfer case bolts on. The 6R80 is right at 23.75 for the same measurement. The big difference is going to be in the adapters and Atlas, so I can't form any conclusions yet.

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