Transmission swap questions.

Articul8ed

Active Member
Joined
Aug 23, 2013
Location
Jamestown
I have a 05 wrangler unlimited Rubicon I'm looking at swapping to a LS setup preferably a LQ9 but I can't decide what transmission is good for my needs I'm crossed between a 700r4 and a th400 I've viewed through threads and of course the th400 is alot stronger but this is a street driven weekend warrior.. I'd say 60/40 to street/trails .. I'm a noob to automatics so any advice would be nice ..
 
For the life of me, I can't see why you wouldn't use a 4L60E or a 4L80E. Then it can all be controlled by the ECM and will work just like stock, you'll have overdrive either way, and there's no TV cable to fool with like on a 700R4.
 
are you concerned about mileage?, this will determine whether you need overdrive or not. I drive my CJ to the trails so overdrive was imperative, hence I ran a 700r4 behind my 6.0 4L80's were expensive ($900) at the time- and 700's were $200, so I chose not to use the 4L80. If I were to do it again, I'd run the 4L80 if I need OD or the TH400 if I didn't.
 
If you go with a non electronic trans, it's easy to adapt but if you want electronic controlled, go for it.

I chose a th350 to get away from electronics and simplicity but mostly affordability (and it's pretty short to work well in the buggy)
 
Chevy NV4500 seems like a good candidate. :driver:
 
dont forget to factor in the reprogramming cost of the ecm if you go with a non electronic transmission.

4l60/4l80 is the "right" answer here.

th400 if you are just stubborn and want ultra reliability.

i wouldnt run a th350 or 7004r unless it was free and even then id probably sell it and buy a 60/80
 
rockcity said:
You are going to reprogram it with whatever you do. ;)
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A whole bunch of people start with this assumption. I would like to challenge that thinking.

Yes on a pure offroad buggy maybe, maybe it makes the most sense. maybe. but for a street used vehicle why?
Ill hang up and listen
 
I'm new to automatics I need a good trans to drive 3 hours to the beach or mountains but a good candidate for offloading as well fuel mileage wold be a plus I'm currently sitting at 4inch of lift on 33s but upgrading to 40s once all my parts come in. Guess alil afraid of the electronics part of it that's why I didn't consider a 4L60, and I'm curious is painless has a harness to run it being the jeep harness will get removed
 
The harness should be reworked as well so you get rid of everything you won't be using if you want to do it right. As well, to do it right you should re flash it to get the best use of your new swap. You'll need to delete the rear O2 sensors and the security features so it actually starts and runs like it should. :)
 
Articul8ed said:
I'm new to automatics I need a good trans to drive 3 hours to the beach or mountains but a good candidate for offloading as well fuel mileage wold be a plus I'm currently sitting at 4inch of lift on 33s but upgrading to 40s once all my parts come in. Guess alil afraid of the electronics part of it that's why I didn't consider a 4L60, and I'm curious is painless has a harness to run it being the jeep harness will get removed
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The motor has a comm circuit with the transmission. Thats why I suggest using the 60e/80e. The motor is looking for feedback. In order to use a "dumb" transmission you have to fool the motor into thinking it is hooked up to a manual transmission. Easy enough to do with some programming or the right ECM. And as Rob suggested there are other "features" you may want to delete. You certainly might want to in a buggy.

In your shoes, I probably would want to keep things like O2 trims and anti theft. They provide a value on a daily driver, imho.
 
For simplicity, I would also go with the 60/80. But as I run a 60 in my Burb, I have never looked at the length differences, that may or may not be an issue. Also, in the wheeling side, I am not sure what your choices are as far as the t case.
But I can say the 60 I run has been a good one. I am at 215K and zero issues(I may regret I wrote that).
 
Ron is correct that if you use a non electronic trans that you have to program the ECM to think it has a manual trans.

VSS, speedo, etc comes into play if you want to know how fast you are going and how to adapt to your factory gauge(s) as well as temp and pressure sensors.

Are you using factory gauges or aftermarket? The ECM you get may need to be different depending on gauges you want to use. For instance, most of the ECMs don't have provisions for oil pressure readings except the 04 GTO and a couple others.

Also, are you using a DBW or DBC throttle body? DBW will require the factory GM pedal.

I would think you would want security but most people that swap the motors disable it as that module is typically tied to other features of the vehicle that you have likely removed due to the swap. I don't know the details but most of the ECMs have a security feature (signal from a module liky deleted or no longer in existence) that will need to be disabled before it will crank.

The system typically has 3-4 O2 sensors. Most people in swaps delete the rear O2 sensors and use the manifold sensors only. Actually, I don't know if anyone that uses the rear O2 sensors during a swap. You can program those out and could program the manifold sensors out as well but the ECM won't be able to learn and the engine could tend to run lean and get poor MPG.

Just a few little things to think about.
 
Well I seen that novak have a adapter setup to where I can run my 241 out of my rubicon until I can afford to do a transfer case swap.
I would love to keep my factory gauges as some will work but rpm and speedo won't jeep has a different crank signal, so I can either run full autometer gauges or try to get mine to work.
I would like to the DBC, and security isn't a issue I have a self top so I leave the door unlocked to prevent a slashed top, as far as the rear 02s go I'd do that but I don't won't to murder my mpg as it gets 11 now ..
 
I was talking with dave at Olivers today about the different harness setups I would like simplicity but that costs 1500^ to have a converson harness made and cleaned up for your application, there a few splicing both jeep and chevy harnesses together
 
There was a guy who put a 6.0 into an XJ and used all the factory gauges. It's expensive but can be done.

XJ 6.0L LS Swap - JeepForum.com

He piggy backed the jeep ECU off the GM ECU. I have no idea how that is done.

As for tranny, I would most definitely go with the 4L60/80 since you say you want to keep your street options. The link I posted also has some videos in it. With an LS swap, the right tires and gears you should be able to get 15+MPG when driven right, according to my professional internet knowledge. I have no real world experience, my opinion is really of no value, I just read about a lot of stuff I can't afford to do.
 
77 green machine checked out that forum that was a sick setup, the down fall is he didn't give details as far as matting the two ecm together or cleaning up harness, that would be my short coming and needing help. The fab and mechanical side of it .. I can do.
 
Articul8ed said:
77 green machine checked out that forum that was a sick setup, the down fall is he didn't give details as far as matting the two ecm together or cleaning up harness, that would be my short coming and needing help. The fab and mechanical side of it .. I can do.[/QUOT
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Yeah that was the bad thing, then the thread fizzled out. I just figured it would be good to let you know it can be done and you know what to search for. May be worth joining that forum just to contact the guy.
 
He posted his number in one of the pages I'll send him a text and pick his brain, once I get all the parts I'll start a build thread on here when I'm half way through it so it doesn't fizzle out
 
Ron said:
A whole bunch of people start with this assumption. I would like to challenge that thinking.

Yes on a pure offroad buggy maybe, maybe it makes the most sense. maybe. but for a street used vehicle why?
Ill hang up and listen
Click to expand...

It may not have to be tuned, but it'll need certain DTCs disabled. Rear 02s, EGR, transmission codes, possibly EVAP disabled, or electric fans added and controlled by coolant temps through the ECM...there's a lot you can do. Either way, you'll have to go in to the ECM. There's always a benefit to some good tuning anyway. They're dialed back some in stock form and you can pick up a good 20 to 30 hp and 1 or 2 MPG.
 
Ultimately it must have had the nessecary readiness codes avalible to pass the inspection....that's one ofor the biggest factors about it
 
Call Jims performance - he'll talk you through all you need to know. He did my harness and asks answers all the questions that you have.
 
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