Aisin AS68RC Tech Tips

The Aisin AS68RC transmission was introduced in 2004 with Mitsubishi trucks AS6, soon followed by Dodge/Sterling bullet in 2006, as well as in Isuzu trucks, which is called the A465 transmission. UD trucks call this transmission the M036A6. this is six speed automatic with lock up torque converter clutch.

The required transmission fluid for the Aisin AS68RC transmission is Exxon JWS3309, or Mobil ATF-3309. Dodge sells as AS68RC fluid. do not use Dexron or Mercon fluids or any other kind of fluid in this transmission or damage will result.

For some Free technical information such as pressure testing transmission,  applied elements and some pinout tests you can perform on the Aisin AS68RC transmission please follow this link to view PDF document.

Aisin AS68RC Pressure switch codes:

Multiple or random pressure switch codes, may be intermittent or hard faults. these are set because TCM doesn't see switch feedback after shift or during Gear commanded at anytime, we have seen many times a valve body gasket blown out causing these codes. also valve body/valve issues such as debris sticking etc. rarely is it the actual switches.  You can pull off pan and sometimes see valve body gasket pieces hanging out the sides of VB. other times its in between also.

Can be wiring problems too, such as chaffed or broken, corroded wires between transmission and TCM. Check circuit of suspected switch. If pan is clean and you've checked circuits between transmission and TCM then likely in valve body area. Also see "severe overheating" below.

No Forward movement in D range. Will move in manual low:

 Truck will not move forward unless shifted to manual low position, has reverse. the F1 sprague in the rear of the transmission has failed. This can be replaced by removing the rear extension housing and or transfer case, and output shaft components.

Severe overheating, slipping in 4th,5th and 6th gears or possible no movement.

Common problem with this transmission can be that the stator shaft has turned in pump cover. can cause no movement, converter overheating, and or slipping in 4th, 5th and 6th gears. A competent machine shop may be able to remove and key the stator back in place or you must purchase a new valve body and pump assemblies from the dealer. If replaceing pump cover beware to use pressure regulator valve spacer set up out of old pump cover as valve body is calibrated to these shim set up/regulator valve settings.

Dodge trucks only, soft shifts and or burnt clutches.(Engine programmers)

Transmission shifting very softly, all clutches may be burnt, If adapts reset no change is felt. There may be diesel engine performance enhancement program installed in the ecm. the problem with this is some of these programs did not address the transmission and then the increased horsepower is too much for the transmission and the shift adapts freeze due to the engine enhancements. this will burn up the transmission repeatedly. some of the companies offer way to remove these programs from ecm. if not you will have to replace the engine ecm.