'98 RHD Mail XJ Auto Transmission Question

I searched around and haven't found any solid information besides that in '98 the computers for the AW4 changed.

My mom delivers mail in an automatic RHD '98, and it recently started to slip a little bit from 1st to 2nd gear. My dad took it to a transmission shop after having the codes from the check engine light read. The scanner said that some kind of transmission sensor was bad/went out, so they had it cleared to pass emissions. The light came back on a few days later so they took it to a transmission shop.

The transmission guy is telling my dad that the XJ has some special transmission that only came in '98 RHD, and he said that the computer locks them out from permanently clearing it. He also said that the parts are different and harder to find, and also stating that the transmission is only manufactured by Toyota. I know Aisin is a supplier for Toyota transmission, thus the AW4 name designation (Aisin-Warner)...

Aren't the internals and sensors of the '98 RHD AW4 going to be the same as +'99 XJs?

I'm calling BS, any insight into this?? Thanks.

I really would not think that there is anything different. At all.

1) The AW4 isn't difficult to find parts for.

2) Most cases of transmission "slip" or "chatter" are caused by varnish - all it wants is a good cleaning most likely.

3) Check to make sure it's a four-speed. If it is, it's an AW4 - if it's a three-speed (no overdrive,) then it's probably a 32RE. A lot of the "fleet" XJs (designated "X1" on the VECI label instead of "XJ") came without the overdrive - since they don't usually spend time on the freeway, it's not needed. Therefore, the three-speed was installed (being both an "in-house" slushbox and less complex made it cheaper.)

Just checked - I've got 1997XJ and 1999XJ FSMs, but not 1998XJ. I could bracket the thing for you, but I can't dial in on it - however, I would find it highly unlikely that the transmission sensors and suchlike would be different RHD vice LHD. However, I do think it a good idea that you verify which transmssion you actually have - the sensors and parts for the 32RE damned sure are different from those for the AW4!

5-90 said:

1) The AW4 isn't difficult to find parts for.

2) Most cases of transmission "slip" or "chatter" are caused by varnish - all it wants is a good cleaning most likely.

3) Check to make sure it's a four-speed. If it is, it's an AW4 - if it's a three-speed (no overdrive,) then it's probably a 32RE. A lot of the "fleet" XJs (designated "X1" on the VECI label instead of "XJ") came without the overdrive - since they don't usually spend time on the freeway, it's not needed. Therefore, the three-speed was installed (being both an "in-house" slushbox and less complex made it cheaper.)

Just checked - I've got 1997XJ and 1999XJ FSMs, but not 1998XJ. I could bracket the thing for you, but I can't dial in on it - however, I would find it highly unlikely that the transmission sensors and suchlike would be different RHD vice LHD. However, I do think it a good idea that you verify which transmssion you actually have - the sensors and parts for the 32RE damned sure are different from those for the AW4!

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Another good way to ID the AW-4 is to look at the drain plug - if it calls for Dexron ATF, (D-II on the plug) then it's an AW-4.

If it's been serviced by any Jeep dealership or many small garages, it's most likely got the wong ATF in there. Dealers assume that the transmission is a Chrysler tranny, since it's in a Chrysler vehicle. The first clue that they're wrong is the longevity of the AW-4...200,000 miles+ is pretty easy to attain. Try that with a Chrylser.

Determine which tranny mom has. If AW-4, drain it and refill with Dexron-III. Drive. Enjoy.

Jim www.yuccaman.com

Thanks for the information guys. I'll find out what transmission it has today. I have a '99 XJ, my brother has an '01, and my mom has another '96 so I should be able to confirm that it's an AW4 . I'm 99% positive it's an AW4 since I remember it having overdrive.

Find another transmission shop. Sounds like they're snowing you.

Pull the codes and see what the error code is. On a 98, the error codes are pretty specific and most times point you to the exact sensor or problem.

In all likely hood a fluid change with the proper fluid will be an improvement. Use Dexron III, not ATF4 becauase as you noted its not a Chrysler tranny.

lawsoncl said:

Find another transmission shop. Sounds like they're snowing you.

Pull the codes and see what the error code is. On a 98, the error codes are pretty specific and most times point you to the exact sensor or problem.

In all likely hood a fluid change with the proper fluid will be an improvement. Use Dexron III, not ATF4 becauase as you noted its not a Chrysler tranny.

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That's what I've been telling my dad. I was talking with him today, and he said the transmission was serviced before they got it. I'm thinking if the AW4s are that sensitive to the different fluid, they're going to throw codes if the wrong fluid is in there. My dad wasn't very specific about exactly what codes were flashing besides the fact that they had to do with the transmission sensors, but I'll show him this thread tomorrow. Thanks for all of the input guys!

JPWilson said:

That's what I've been telling my dad. I was talking with him today, and he said the transmission was serviced before they got it. I'm thinking if the AW4s are that sensitive to the different fluid, they're going to throw codes if the wrong fluid is in there. My dad wasn't very specific about exactly what codes were flashing besides the fact that they had to do with the transmission sensors, but I'll show him this thread tomorrow. Thanks for all of the input guys!

Click to expand...

NB: OBD-II won't throw a code for the wrong fluid in the slushbox. At least, not specifically... It may, however, throw a code related to a malfunction caused by the wrong fluid, but it will require some thinking on your part to diagnose properly (a "sensor failure" typically isn't caused by the wrong fluid, tho.)

The most common reported problem with using ATF4 is slippage. If the shop that "serviced" it put the wrong fluid it that could explain the slipping. Without pulling the codes, you cant be sure where to start. Heck, it could have a been a code for the range selector switch, more commonly called the NSS switch.