Allison Transmission Questions

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

  1. larry6053

    larry6053 New Member

    Allison Transmission Questions

    I have an Allison at 545 in a 92 Bounder motor home with a 5.9 Cummins, I have destroyed the trans twice now and have been told that the exhaust brake is probably the biggest contributor to this. I was also told that since I have tweaked the motor to apprx. 300 HP that may be a problem too. I have removed the exhaust brake (it came with the coach when I bought it used) but would like to know if detuning the motor is necessary also. Is ther any way to get a locking torque convertor for this trans? Thanks for the help
     
  2. transrand

    transrand New Member

    Allison Transmission Questions

    larry6053:
    Yes you are running too much horsepower for the transmission. I am not sure why anyone would put on an exhaust brake when there is a non lockup convertor. There is a company I heard of that sells a lockup convertor for an AT 545 transmission, but I am not sure what company made it. I will check around and get back to you if I figure anything out.
     
  3. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hello Pilotreef,
    Sorry about the late response but I had retired a lil from this, but I can't let it go LOL. I can only think that your problem may be a sticking throttle position sensor at your engine throttle linkage. If the TPS is stuck and not returning properly, the Allison computor will think you have your foot on the throttle and be more than 10% throttle showing to the computor and it will not go into gear. Try putting a light throttle return spring on the TPS to get it to return or replacement would cost around $300 for a new TPS. I hope this solves your problem. Thanks and have a great day! :)
     
  4. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Chriss,
    I hope you read my response for pilotreef. Another problem you may have is if there is any debris that may have gotten inside your shift pad.If anyone spilled anything or just sometimes the electronic board inside needs to be wiped off. I hope your problem is resolved. Thank you and have a great day! :)
     
  5. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Champtoyou,
    Uh Oh, I do not recommend 2 things at least that you have modified on your truck. It sounds wonderful and I would love to own it LOL but by adding taller tires and adding horsepower, you basically have written off the Allison warranty. Taller tires change the output ratio and the transmission will shift out of its normal torque curve. I do not have the horsepower rating here at home but I can get it if you need it or call your local Allison distributor or dealer.
    Well back to your question. The filter is the spin on, oil looking, filter. Make sure you save the magnet that usually sticks to the top of the filter and put it on the new filter. The original filter change is suppose to be at 5,000 miles. Have a great day! :)
     
  6. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Vixen21td,
    Regearing with an Allison MD3060 is very expensive. Not only do you need a transmission (with no core approx $7000) you need an ECU (computor $1600), programming ($500) shift pad (1000) and this still does not include labor. It can be done but very expensive. If I can help any more, please contact me at phone # in earlier posts. Thank you and have a great day! :)
     
  7. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi canadayco,
    There is only one calibration for the pick-ups, but there is a possibility that if it is not shifting correctly, your original calibration may have some updates in it. Contact your local GMC dealer and if they do not help you, call your local Allison distributor and see if they will help. Thank you and have a great day! :)
     
  8. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi GonlyLonely,
    No the Ford is not an Allison. At this time, GMC and Chevy are the only pickups that use the Allison. The larger Ford 650 does have the Allison. It is considered a light duty truck. Thanks and have a great day! :)
     
  9. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Larry653,
    You are correct on both accounts. You will keep burning up the AT545 unless you remove the PAC brake system (which is doing no good since your transmission has no converter lockup). When a transmission has converter lockup, it locks one to one with the engine which in turn in combination with the PAC brake system, slow the vehicle. Tha AT545 has no lockup and runs in hydralic converter faze 100% of the time. With hydralics, you make friction, heat and sooner or later, transmission failure. The AT545 is a good transmission, but if you want holdback, the MT643 would be a great conversion. It is a cost effective way to go also because you can get a rebuilt one for a resonable price. The engine will have to go from a #3 housing to a #2 SAE housing and the flexplates and engine adaption pieces will need to be changed. Good luck and have a great day! :)
     
  10. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    KJS 1995 eagle,
    I believe I answered your question at work but I will again. If you remove the wire attached to your temp sender and with the key in ignition position, ground the wire to the chassis (trans case is good ground), if you gauge pegs all the way to the right, your sender is bad, if the gauge does not move, check for opens in the wire, then if no opens, your gauge is bad. I hope this helps, Thanks and have a great day! :)
     
  11. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Weekender,
    Thank you!
    I think I also ansered you from work since i have not looked here for a while (I tried to retire but can't give up LOL) E-mail me at work where i have a booklet of distibutors and dealers.
    NOTE to everyone:If you go to allisontransmission.com and look in the upper right hand corner of the site, click on locations for service. This is a new system and is really cool. Just click on continent, country, etc until you get to your local area. Not only does it give you names of service distributors and dealers, but tells you everything about the facility including drivers lounge. RV hookup, etc. Try it you'll like it hehe. Thanks and have a great day>
    rfranzen@pacificdda.com
     
  12. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi 2 DA WDS,
    Try your local GMC dealer and see if they know of a calibration fix for shift bussiness. I would take it to a GMC dealer that also sells not only pick-ups, but bigger GMC's. They seem to know more about the Allisons. Thanks and have a great day! :)
     
  13. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Garyp,
    Using your economy mode is exactly what you should be doing. Is this happening pulling hills? This is where I hear most of this problem. Economy mode was made to render this situation. You did a great job figuring that out. No harm will be done at all to your transmissions. Enjoy the ride! Have a great day! :)
     
  14. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi Bill SR,
    It can be a stuck govenor but what I always check for in this situation is the engine no load rpm. Is this diesel? If so, put your trans in nuetral and step on the throttle. Record the rpm that the engine stops at. Next, there is a tag on the right side of the transmission that has a part number on it. Write that down and call local Allison parts facility and ask them what rpm transmission you have by giving them the part number. If they ask why, just say you need a transmission and they should help you LOL. The engine RPM must be a minumum 150rpm higher than what the parts department says your transmission is. For example, they tell you your transmission is a 2600rpm. Your engine would need to go to a minumum 2750 rpm in nuetral. If you are only turning 2650-2700, this is why transmission will not shift. Good luck and have a great day! :)
     
  15. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi unclecarny,
    I hope your truck is still under warranty. There is a new spring in the front support that needs to be put in. The problem is oil drainback. If your truck sits for a period of time, the oil is draining out of the torque convertor and loses lil prime and takes a while to fill up.This spring will fix your problem. If you have any questions, I have the sevice information letter at work. Please e-mail me there and I will scan it and send it to your E-mail. Thanks and have a great day! :)
     
  16. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi mudman,
    I think what you meant is it was behind a gas engine and is now behind a diesel. The valve body rpm is different. I hear this a lot with regears. People need to know there is more to it than changing transmissions. There are torque convertor ratios, speedometer gears, pto or non pto, pan depth and the big one that gets most people, RPM. You need at least the engine rpm on the valve body recalibrated (re-sprung and tested) to 150 rpm lower than your engine no load governed rpm. I hope this helps. Thanks and have agreat day! :)
     
  17. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi cepenno,
    Please give me a call and I can answer all your questions. Or e-mail me at rfranzen@pacificdda.com. I will certainly give you all the help you need. You are a local person and I would love to help even if you do by yourself. It is easy I can walk you thru it. The oil if Dexron does need changing every 12 months due to the condensation that builds up inside the aluminum case. Dexron does not like moisture, it breaks down. I would suggest converting to synthetic Castrol Transynde. It is expensive but pays for itself. At 75,000 miles you just change filters not oil and do an oil sample every couple years. It also maks the trans run cooler and really saves on wear and tear. I do not make any more money selling dexron or tTransynde so I am not trying to sell you Transynde, its just that **** good LOL. E-mail me and I will give you my phone number through E-mail. Have a great day! :)
     
  18. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    grldst,
    I would have this checked out. You may have a wiring issue or a bad sensor. Check allisontransmission.com and you can click on service locations up on top right. Good luck and have a great day! p.s. 2 qts overfill will be ok until it is checked. :)
     
  19. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    Hi barbicj,
    I would check the oil level first. When it warms, it expands and if you are low, after travel it goes higher on stick and stops the slipping. Another thing I caution is their may be a cracked C2 clutch hub inside the transmission. You may want to have this checked out. Good luck and have a great day! :)
     
  20. AllisonMan

    AllisonMan New Member

    Allison Transmission Questions

    hi driver8,
    Did you see my earlier reply on the front support spring? Your problem sounds like a bad NSBU (nuetral safety back up) switch. Does your display change even though you do not move it or some times not light? Have the NSBU checked out. I would not recommend replacing yourself because these are very sensitive and need to be adjusted precicely. Thanks and have agreat day! :)
     

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