2004 TJ 42RLE automatic transmission into 2000 TJ

[fastdeuce]

Has anyone swapped in a 42rle automatic transmission from 2004 TJ into a 2000 TJ?
Jeep changed the shift cable, the metal adapter in side the cabin for the shift lever and the plastic console between the years so they don't match and make an easy swap

 

[Jerry Bransford]

If you simply want to convert a manual transmission to an automatic then I'd go for the 3-speed 32RH automatic. The 42RLE requires an external transmission control computer to operate it that I don't believe will talk with your 2000 PCM. The 32RH needs no computer and it's basically a fairly bolt-in job. I did that conversion with my previous '97 TJ, even the required wiring is already there in TJs that came with manual transmissions.

Not to mention the 42RLE's .69 Overdrive ratio is so steep and drops the engine rpms so far you have to regear both axles to extra-low ratios so the engine will be able to generate enough power and won't lug.

 

[AndyG]

Man listen to Jerry-

What you’re looking at is the hardest way to get the least desirable automatic transmission.

There is a saying that when something works really good you don’t even notice it- The 32RH transmission is that good. It brings out the best qualities of the engine, It makes it the most well-rounded power train combination they ever offered.

 

[AndyG]

Kind of funny no 32RH owners complain of low power, or regear much. So much of the problem is the transmission.

The 42 RLE was an era of manufacturing between the good basic nonelectronic three speed transmissions and the 6, 8 and more speed automatics today- The advent of the newer transmissions was to make an electronic overdrive transmission better utilize the power of smaller, peaky engines- And they do.

The 4.0 would be fabulous with an 8 speed auto but since that is out of the question it belongs with the transmission of the same era as it- the 32 RH.

If you look back in the last 30 years you’ll see a lot of three speed automatic transmissions that have legendary reliability- the Ford C6, the TorqueFlite, and many more.

The 4.0 is not a perfect engine by any means, But it shows up for work every day. Even though it was laid off a long time ago.

 

[fastdeuce]

That is very good information. I appreciate your comments: especially about the gear ratios.
I'm doing a full swap: engine, transmission, engine computer, and wiring (plus more), and not converting from manual transmission. I actually have a full donor 2004 Jeep TJ I bought at auction with < 18K miles so I am using all its components and have almost all harvested out and already installed in my 2000 TJ. Very few incompatible parts except this difference in interior AT shifter metal mounting plate and the interior console.
I know how to resolve the mounting plate issue.
-I'm interested in knowing if anyone else has a solution for the interior plastic console incompatibility.

I'm not planning any offroading with this Jeep. I have a 350cc dirt bike for that type of fun

 

[AndyG]

That is very good information. I appreciate your comments: especially about the gear ratios.
I'm doing a full swap: engine, transmission, engine computer, and wiring (plus more), and not converting from manual transmission. I actually have a full donor 2004 Jeep TJ I bought at auction with < 18K miles so I am using all its components and have almost all harvested out and already installed in my 2000 TJ. Very few incompatible parts except this difference in interior AT shifter metal mounting plate and the interior console.
I know how to resolve the mounting plate issue.
-I'm interested in knowing if anyone else has a solution for the interior plastic console incompatibility.

I'm not planning any offroading with this Jeep. I have a 350cc dirt bike for that type of fun

@Jamison C might.

I’m all for 2 wheels in dirt.

 

[fastdeuce]

Absolutely. Nice bike man! I ride orange too. 350SXF. Just rode yesterday with friends.

 

[AndyG]

Absolutely. Nice bike man! I ride orange too. 350SXF. Just rode yesterday with friends.

When you said 350 I knew you did-

Guys are going crazy for those things in hare scrambles down here now.

It is just amazing how good Ktm’s are.