View Full Version : AW-4 Toasted???

November 19th, 2017, 04:37
1997 XJ, 4.0, AW-4, NP231, 3" lift, 440K miles.

For the past few days when I start driving in the AM I heard a whining sound that I thought could possibly be the torque converter. I checked fluid, it was full, red and maybe a touch of burnt smell. (It's been 12K miles since last fluid change.)
At that time the shop put in 5 qts of ATF+4, and 2 qts of Dex/Merc. He didn't have all 7 qts of Dex/Merc and he said that this would be OK.

Yesterday I went trail riding and on way home on the Interstate the transmission apparently died. My engine RPM's went over 3000 and there was no power to the wheels. It was like the Tranny was in Neutral. Had to be towed home.
This tranny was bought brand new and has 153,000 miles on it.

Anyway, is the Tranny toasted, or could it be a "minor" problem that can be fixed?

Appreciate any help-

November 19th, 2017, 09:26
First of all ATF+4 is a no no for the AW4, second, the AW4 takes 8 qts.


If the transfer case was in Neutral, even if the transmission was in gear, you would get no power to the wheels. Your t-case linkage could have come loose in your trail riding.

...and then find a new mechanic.

November 19th, 2017, 16:53
Test the shift solenoids. Unplug the TCM and see if it shifts manually. Then, find a new mechanic.

November 19th, 2017, 17:14
did the wining sound change with vehicle speed or engine speed?

November 20th, 2017, 06:19
could be linkage broke, could be out of fluid, lot of guessing really

November 21st, 2017, 14:38
At the time of the failure did you check the fluid again? Did you lose power all at once or did the trans start to slip and then completely lost forward gear? Need more info to help specifically.

I'm not AW4 expert, but do know they are pretty tough. Can't comment on the atf+4 mentioned above, but have heard that its not good to mix them, not sure why though.

I would not expect catastrophic trans failure to manifest without some sort of bang, or obvious problem. Try and describe the failure incident in detail and what you checked after you got stopped on the highway? Trans fluid? smells? reverse? shift t-case back and forth?

Let us know