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RKL2 · 10-25-2006, 04:07 PM

on my way south last week, with the Mode on, the Allison shifted quite hard from 4th to 5th. OK in other shift points...With the mode off, the Allison shifted smoothly in all gears....Drove in a lot of rain and thru some mountains in 4th...Does this sound like a reprogramming is in order? A past reprogram solved a hard downshift problem in the past...thanks....RKL

RKL2 · 10-25-2006, 04:07 PM

on my way south last week, with the Mode on, the Allison shifted quite hard from 4th to 5th. OK in other shift points...With the mode off, the Allison shifted smoothly in all gears....Drove in a lot of rain and thru some mountains in 4th...Does this sound like a reprogramming is in order? A past reprogram solved a hard downshift problem in the past...thanks....RKL

AFChap · 10-25-2006, 04:42 PM

We have a hard shift from time to time ...mode off or on. I normally blame it on situation at the time ...normally highway driving up hills when the grade suddenly is less (normally I think when I am not in cruise control, though not sure about that). I haven't ever reprogrammed, and wouldn't really call it a recurring problem ...just once in a great while in similar conditions.

Indyrvfolks · 11-02-2006, 01:29 PM

RKL:

Has the problem repeated itself? Was it a one time, or limited series of occurences or ongoing? Reprogramming is generally not required for Allison products unless you want some other features not currently supported by the calibration. If anything significant is occuring, typicaly a diagnostic code would be set in memory. If your product is a MD 3000 Family (like and MD 3060.... or a MH 3000) then you can read the codes directly from the shifter. Consult www.allisontransmission.com for guidance on how to extract codes (Ign On, Engine Off, push the up and down arrows together... the shifter will begin to cycle through any stored codes) If you have an electronic oil level sensor, the first information is Oil Level, Press the up and down arrows a second time to enter into diagnostic mode. Anytime you troubleshoot, always start with the basics. Does the unit have the correct type fluid and the correct oil level.... Good luck

RKL2 · 11-03-2006, 03:55 AM

Thanks for the responses...My hard shift problem was reoccurring in Mode only setting...Oil level was OK and no codes set...I went to the Allison shop in Ft. Myers and they said the hard shifting would gradually go away with several days of city driving so as to learn a new adjustment...
They also said they could reprogram the ECU and that would correct the problem in 3 or 4 shift sequences...I said do it and it worked...No charge by Allison. Everything is fine now....Apparently they said the hard mountain driving and heavy dingy load was causing a hard clutch pressure pattern to prevent slipping on the steep grades....I did notice a little shudder on several upshifts going up the mountain. allison said that is when the Allison decided to increase clutch pressure to correct the shudder.thanks RKL

Tcloud7 · 11-03-2006, 03:40 PM

Ok I have the Allison trans also But I don't know what mode means. Mine is a six speed and I just put in drive and go. So whats mode mean???? Is this the ones with the buttons??

Thanks Tcloud