tj automatic

adam greene

adam greene

Well-Known Member
Joined
Sep 9, 2008
Location
morganton
i got a 99 tj with a automatic, i wanting to get a over drive gear, is it best to get a aw4 if so what all has to be done to do that, did any tjs come with over drive
 
42RLE four-speed automatic transmission was available from 2003 to 2006

the 42RLE is a 4 speed transmission. 1st, 2nd, 3rd (OD OFF) and 4th (OD).

You push the OD OFF button, it doesn't let the tranny go to 4th gear. this is useful for towing, driving in the hills and 4Lo. This was NOT the transmission in an XJ, that was an AW4.

the 42RLE sucks a lot of power out of the 4.0L, it takes a significant amount of torque to power it, doesn't mean its not a good tranny, but it sure is a pain in the mountains.

Novak.com said:
The Aisin Warner AW4 transmission is an automatic shift, four-speed overdrive transmission used in the 1987-2001 Jeep XJ Cherokee and MJ Comanche models. Its only year in the ZJ Grand Cherokee was 1993, and only with the six-cylinder.
The AW4 is predominatly found behind the AMC 4.0L (242 ci) I6 engine. The AW4 was also used behind the AMC 2.5 four-cylinder. A similar transmission is used in some Toyota RWD applications, known as the A340.
Gear Ratios for the AW4 are 2.80, 1.53, 1.00 & .75.
The AW4 is a light to medium-duty transmission. Ours, our callers' and customers' experiences with the AW4 are less than stellar. They have a tendency to generate excessive amounts of heat, and are known for unnecessarily consuming more engine power than some other automatics. The shift points in the AW4 feel odd, and the spotty engagment of the lockup torque converter is idiosyncratic.
But, it is a decent transmission, and if kept cool and maintained, it can offer good service within its range.
Identification
The AW4 as found in Jeep vehicles has a length of 25-3/8". The AW4 has a removable bellhousing with a port for the crank position sensor. The case is smaller in diameter than most automatics, and features cast-in ribbing down the rear half of the case.
The earlier Jeep AW4 has a 21 spline output shaft for connecting to the transfer case input shaft. With the release of the HO 4.0L in the 1991 the AW4 was upgraded to a 23 spline output shaft.
The AW4 may be identified as a model #30-43LE for 2wd versions and as a model #40-30LE for 4wd versions.

Transfer Case Compatibility
The Jeep AW4 was factory-married to the Jeep Jeep New Process (aka New Venture) Model 231 transfer case, in addition to the NP242 Full-Time transfer case.
It is possible to adapt the AW4 to the Jeep Dana 300 transfer case in passenger side and driver side drop by using Novak kit #153 in the event one is installing a 4.0L into an '80s era CJ.
The AW4 and the 2.5L engine was a rare combination in the XJ / MJ model Jeeps as spec-to-build. They recieved 4.56 axle ratios.

The transmission case and internals were identical to the 4.0L version of the AW4, but the detachable bellhousing and torque converter were unique to the 2.5L I4 engine.

Thanks to J. Janisko for this information.
Engine Compatibility
AMC / Mopar Jeep
As the AW4 was married to the Jeep engines mentioned above, it is OEM compatible with them. The AW4 is an electronically controlled transmission, and is therefore compatible only with the 4.0L engine and its PCM package.
Click to expand...

Jeep Forum.com said:
I wouldn't even ATTEMPT to convert a TJ from a 32RH to the current 42RLE. At a minimum, you need a new wiring harness, PCM (engine computer), crankshaft position sensor, plus you have to modifiy the bell housing to move the crankshaft position sensor to a different location (which requires precision on where it gets placed. Not to mention new flex plate, tranny mount, t-case skid and likely a different t-case shifter as well as who knows what else. Just the electronic side of things would be difficult since a PCM new enough to run the 42RLE would not know how to run your distributor-based ignition since all TJs with 42RLE transmissions use distributorless ignition systems while yours uses a distributor.

I don't think it's a good idea at all.
Click to expand...

Here is a link to a swap out of a ax15 to an AW4
http://www.stu-offroad.com/engine/aw-4/aw-4-1.htm
 
let me know how it works out for you i am thinking about doing the same thing with my 98
 
maddog411 said:
Automatic jeeps are for high school girls! :shaking:
Click to expand...

This is an auto were working on.

ai298.photobucket.com_albums_mm279_burrellsjeep_mvc_009f.jpg_ca69a74c4969188f57f0808621df72b1.jpg


That is if the High School girl lets us ride in it :flipoff2:



P.S. Thats the same thing I told him when he got it
 
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