Allison Transmission Questions

Discussion in 'General RVing' started by AllisonMan, Apr 5, 2003.

  1. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    It it's still got the two-bolts with a locktab output flange, the torque is 30 - 35 Nm on each bolt.
     
  2. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    Hi Allison Man!

    I have a 96 Monaco Dynasty with a 8.3 Cummins, Allison MD3060, World Transmission & King Control.

    I have been shifting issues, both in cruise control & manual driving. I've had the rig to a mechanic & he was not able to find any issues. Recently, I had an issue with the King Control & found no solder at the 12 volt power at King board. I soldered the 12 volt wires to the King board. However, intermittently, the transmission display will illuminate "SERVICE" & will downshift & then sift back to 5th or 6th gear. This is what happened yesterday after a 20 minute drive.

    In the past, prior to soldering the King board, it has also shifted to neutral.

    I've talked with Steve at King Control, he claimed that the King Control will not cause the transmission panel to illuminate the SERVICE light. He did recommend that I send the King control for refurbishing ($475).

    I would like to know how to read error codes from the transmission display & if you think it is possible that the King Control could be causing the problem.

    I'll be glad to provide any other info that may help in diagnosing the problem. I look forward to your reply.

    Kevin
     
  3. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    Rig has about 50,000 miles & fluid filters were changed last November. Only a 100 miles on the rig since the fluid & filter change.
     
  4. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    If you have a WTEC II transmission, here's a link to the Allison Mechancs Tips booklet that has the procedure in it for checking codes.
    http://www.allisontransmission.com/publications/pubs/MT2159EN.jsp

    If you have WTEC III, here's the link to the mechanics' tips booklet:
    http://www.allisontransmission.com/servlet/DownloadFile?Dir=publications/pubs&FileToGet=MT3004EN.pdf

    Here's the King Diagnostics link:
    http://www.cruisecontrolking.com/cruisediagnostics.html

    Please read the codes and let us know what you find.
     
  5. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    Thanks! The transmission is displaying codes 21 & 23. Could the King Control cause these TPS codes?

    Thanks.

    KC
     
  6. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    I got my answer from Steve at King Control. The 2600 will put out bad TPS signals & cause the codes. Shipping the unit to King Control. Actuator, board & a harness will be replaced.

    Thanks!
     
  7. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    I agree. The King interfaces with the trans TPS so it can be a cause.
     
  8. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    I sent my KC-2600 to King Control for repair. I received a call from Steve at King Control today & he say he replaced the circuit board, wire harness, servo & the mechanical accelerator cable.

    He did a bench test on the unit & still had a bad TPS (Throttle Position Sensor) signal coming out of the unit. Upon closer inspection, he found an internal only wire connected to a wrong pin. He even said, he couldn't figure how the rig ran at all, as it was the KC-2600 was not putting out a valid TPS signal.

    The unit is being shipped back to me. If there are further issues, I'll post to the board.

    Thanks,

    Kevin
    96 Dynasty
     
  9. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    So did they charge you for putting the wire on the right pin or did they charge you for all of the stuff might not needed to be done?? :question:
     
  10. Kevin C

    Kevin C New Member

    Re: Allison Transmission Questions

    The other stuff needed to be done. It's pretty well documented on the URLs shared above. Pins 21 & 22 of the circuit board connector were burned, a sign of too much current draw of the old style board & servo.
     
  11. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions



    dB, I have finally taken my motor home out for the test drive that you had suggested, only 4 months to do it. Starting the engine - no problem, engine idle - no problem, putting her in gear - no problem, running engine at high idle - no problem. The problems start when I have it in drive or reverse. I cannot get any rpm's while in gear. I did manage to get her out on the back roads and my top speed was 30 mph and she did shift into 4th for just a few seconds then back to third. On a 3% grade was just a crawl. Also took about 1.5 miles to get to 30 mph. Got home ok, check air filter = 7" W.C., brakes not hot, My driveway has a 2% grade. I tried to take her back to the top of the drive way, no deal. Right now there is no difference between idle and full throttle on the peddle while in gear. Water/fuel separatorand fuel filter have only 900 miles on them. At one point while changing from R to N I got " + + " on my shift pad. Had to turn off the engine to reset those codes. That only happen once. Well what's your thinking. Really, dB, thanks for any help.
     
  12. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    Ps. There is no "Engine Trouble" light.
     
  13. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    Update, I spoke with Kevin at the Allison place here in Spokane, WA. Kevin said to remove all of the cables off of my batteries and do a good cleaning. Ok I did. Took the home for a drive. Did very well, thought I had solved the problem. Well as I was driving it felt like nothing would happen while pushing on the pedal but just a little hesitation. Climbing small hills was ok for the first two miles. Got her on the flat and she went right up to 40 mph in 4th gear and that was all she would do. Would go into 5th. but would not stay there. By the time I got her home, it was I could do to get her into the driveway. Would not shift down to first just to second. Check the air filter and the indicator is setting at 10" W.C. The total test drive was 4 miles. Still no fault codes or engine trouble light. Brakes not hot. :(
     
  14. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    This is a tough one.

    I would normally recommend a stall test, to separate engine problems from transmission problems. Start the engine, set the brakes, keep everyone away!!! Go to wide open throttle and record the speed the engine gets to. A local Cat or Allison place should be able to tell you the proper stall speed for that engine/trans combination. A low stall usually indicates engine power problems.

    I would go ahead and do the stall test just to know the results. However, if the problem occurs only going down the road, and with no transmission trouble codes, I'm leaning toward an engine problem like a sensor not reading correctly. I would take it to a good Cat distributor and have them plug in the Cat Electronic Technician. Make sure all the sensors (temps, input voltage, turbo boost, throttle position, etc.) from the engine are reading values that make sense for the conditions. Sometimes a turbo boost sensor or something can fail and not be so far out of bounds it causes an engine code.

    If that doesn't show anything, do the same for the transmission. Have the Allison place plug in Allison DOC and watch the sensors - temp, speeds, input voltage, throttle position sensor. Make sure the readings make sense.

    Keep us posted. This one isn't an easy one. Now watch, it'll probably be something simple I should have known.
     
  15. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    The cat eyes you got on the selector that one time concern me. That means the ECU and the selector were not communicating. Might have been an intermittent, but may indicate a problem with the selector, ECU, or the connection between them. If the selector is remote from the ECU, this could be a wiring problem. If the selector and the ECU are integral, maybe an ECU or loose ribbon cable inside. Hard to say. I'd still take a look at all the sensors with the appropriate diagnostic tools, if you can get that done.
     
  16. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    Not sure if I understand the Stall Test. Start the engine, set the brake, put into 1st. gear????, record top mph's or rpm's???

    This will be a costly one. I am not going to try to drive her in to town and I really don't want to have her towed so I guess I will have to have CAT and Allison come out here with their computor's. I spoke with CAT and the gentlemen there said to start with Allison. However I would like to try this stall test first. Thanks dB.
     
  17. LEN

    LEN Senior Member

    Re: Allison Transmission Questions

    Hey Triple E, with the more info you might change both fuel filters. $30-$40 might just cure. Kinda starting to sound like lack of fuel or boost. Either I would think would throw a code.

    LEN
     
  18. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    Len, I have only 900 miles and 7 months on the filters. But we both know that doesn't mean anything. I am leaning that way. The filters are Donaldson's but that doesn't mean anything either. :(

    db, ECU+CAL assy # 295243308, Model: MD3060, T: Basic, CIN: 08004T8012G. Next to the ECU is a black box that states - 12V, 6 Relay, P/N 29509886.

    I have one thing bothering me. There is a rose white 10ga wire connected to the negative post on the battery. Up stream of the battery on this wire is a relay and a 20 amp fuse. I have never seen a fuse or relay on the negative side. Always on the positive side. But it has been this way since I bought her. I have thought about moving it to the positive terminal but scared too.
     
  19. dbarton291

    dbarton291 Senior Member

    Re: Allison Transmission Questions

    Yes, put into first gear and record max RPMs. It's called stall test because the turbine side of the torque converter is stalled, or at zero speed, when you are in gear and not moving.

    If the engine's making power sitting still, the stall will be normal. It the stall speed is low (engine RPM), the engine is down on power under those conditions.

    The procedure should be in the mechanics tips booklet. I've posted a link to that book several times.
     
  20. Triple E

    Triple E Senior Member

    Re: Allison Transmission Questions

    Ok db I found it. I will do this first thing in the morning. Thank you very much. I will let you know what I find. So I am assuming that if the RPM's are low I take her to CAT. If the RPM's are high she is headed for allison.
     

Share This Page