transmission hard down shifts, also going into default


gmoody

New Member
1994 Dolphin pusher w/cummins diesel, Allison 3060 transmission down shifting hard shifts especially from 2nd to 1st. Had transmission serviced with new filters and fluid, all fluids show ok, dealer said needed to drive a while and shifting should get better, now have over 500 miles and down shifts still harsh. Up shifting seems to be ok and in normal range. Did have a problem when fuelling once. wouldn't go in gear, had been driving for a couple of hours and stoped to fuel up and when re-starting, wouldn't go into any gear. I checked the monitor and was flashing and retrieved 2 codes, 45 & 22, I cleared the codes and restarted and went into gears ok and seemed ok. I took the MH out 2 weeks later and it went into default again, cleared codes and off again we went. Any suggestions?
 

Triple E

Senior Member
Re: transmission hard down shifts, also going into default

Our transmission guro is out of the country right now but does check in from time to time. He is the best and I am sure he will be able to help you out. Would it be possible to provide the serial number on the tranny? This might help him with your answer. So please stand-by.
 

dbarton291

Senior Member
Re: transmission hard down shifts, also going into default

I am back in the country, but I'm off work for a couple of weeks. I was in Asia for a little over a month, so I'm still not 100% right now.
Code 45 22 I believe a an open in the solenoid G circuit. I'm not in the office, so I don't have a code chart with me. It sounds like you're getting an intermittent open in the wiring harness causing the intermittent code.

Run the harness for opens, shorts between wires and shorts to ground. Since it's intermittent, you'll have to wiggle and tug and look for any sign of a possible worn spot, or intrusion into, the harness.

Have the harsh shifts always been there, or is this something new?
 

Allison Expert

New Member
Re: transmission hard down shifts, also going into default

Depending on the S/N this could have something to do with it possibly having the old style seperator plate that the temp sensor would rub on and through weird codes. I have also seen them do similar things as this guy is complaining about. With it being WTECII, it will take longer to adapt itself if the computer has never been reset. The trans won't adapt itself if codes keep coming up. Just a thought..
 
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