Help! Allison transmission control problem!

This evening, Vita and I went to the storage lot to take Evangeline for fueling in preparation for a trip to Chattanooga, TN this weekend. She started and aired up fine, but when I got ready to roll and punched the "D" pad on the transmission shift control pad - nothing!!! :eek: The reverse pad works, the "mode" pad works, but "D" is totally nonresponsive! Has anyone experienced this problem before and know of a "work around" method to get the bus to go into gear so we can roll?

I'm admittedly not mechanically inclined and don't know where to begin to troubleshoot this issue, but I suspect that the problem is in the keypad contacts. Does that make sense? :confused:

Because the bus is in a secure storage lot and won't go into a forward gear, I can't even drive it to a repair shop to have it diagnosed and repaired!

I'm on the verge of being in the doghouse big time with Vita and our daughter because this Chattanooga trip was a Christmas present to our daughter to take her and her best friend to Chattanooga in the bus to see her favorite comedian, Brian Regan (never heard of him before this!) Sunday night! Of course, Vita and I are seeing our favorite comedian, Ron White, at the same venue the night before (Saturday night).

So, I've got to work fast to solve this problem before I ruin the weekend with a broken bus! Can anyone provide some emergency guidance?

Thanks! :o

Michael,

I assume you tried shutting the engine down and restarting to see if that made any difference. Also pull up and push down your emergency brake switch to make sure it is all the way engaged.

Michael, sheepishly I will ask, did you place your foot on the brake pedal before you pushed the "D" on the tranny pad. Just a thought

Several things prevent it from going into drive such as trying to shift on high idle, or if the temperature in the transmission is less than a certain value.

I suggest trying to shift at low idle after warming up the coach.

You also have the ability to read codes so if it still will not shift see if there are active codes which can be accessed and read from the keypad.

We have seen some of the pads that become stiff with cold weather. Try pressing very firmly in the center of the D with the coach @ low idle.

Michael,

The same thing happened to me about 2 years ago. I found that pressing down firmly and rolling my finger around on the "D" would get it to work. It did this 4 or 5 more times so I started looking for a new selector pad on eBay. They were expensive if I remember correctly, about $600 so I just kept looking trying to find one at a good price.

After a month of looking on eBay the problem disappeared! It has been 2 years and the selector has worked flawlessly! Go figure!

Hope rolling your finger on the "D" helps. Just keep messing with it, and it should work.

Quote:

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Originally Posted by Roadrunner

Michael,

I assume you tried shutting the engine down and restarting to see if that made any difference. Also pull up and push down your emergency brake switch to make sure it is all the way engaged.

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Dale - Yep, I shut down & restarted twice and also engaged a disengaged the emergency brake a few times making sure that the button was firmly pushed all the way down.

Quote:

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Originally Posted by Coloradobus

Michael, sheepishly I will ask, did you place your foot on the brake pedal before you pushed the "D" on the tranny pad. Just a thought

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Jim - yes, I was depressing the brake pedal throughout the process. <shrug>

Quote:

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Originally Posted by Jon Wehrenberg

Several things prevent it from going into drive such as trying to shift on high idle, or if the temperature in the transmission is less than a certain value.

I suggest trying to shift at low idle after warming up the coach.

You also have the ability to read codes so if it still will not shift see if there are active codes which can be accessed and read from the keypad.

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Jon - I'm certain that I had switched to low idle before trying to shift. In fact, I shifted successfully into reverse and moved the bus back a few feet and then tried to shift to Neutral and then Drive again. It went to Neutral with no problem, but would not respond when I pressed the "D" pad.

The ambient temperature outside at the time was about 41 degrees and I had warmed the engine up on high idle for several minutes.

I'm unfamiliar with how to read or interpret the codes you mentioned.

Quote:

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Originally Posted by Steve Bennett

We have seen some of the pads that become stiff with cold weather. Try pressing very firmly in the center of the D with the coach @ low idle.

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Thanks Steve - I'm going to try again in the morning and hope to have better luck!

Quote:

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Originally Posted by merle&louise

Michael,

The same thing happened to me about 2 years ago. I found that pressing down firmly and rolling my finger around on the "D" would get it to work. It did this 4 or 5 more times so I started looking for a new selector pad on eBay. They were expensive if I remember correctly, about $600 so I just kept looking trying to find one at a good price.

After a month of looking on eBay the problem disappeared! It has been 2 years and the selector has worked flawlessly! Go figure!

Hope rolling your finger on the "D" helps. Just keep messing with it, and it should work.

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Tuga - while trying to get it to shift today, I pressed the pad every way and from every angle I could think of, including "rolling" my finger on the pad while pressing firmly. I'm going to try again in the morning! Wish me luck!

Michael,

Try the following link from the Prevost online Technical manuals site for transmissions. It has the procedure for pulling up codes on your shift pad. Also has some trouble shooting info and references to other technical documents that may be of help.

http://prevostparts.volvo.com/techni.../pa1082-07.pdf

Ken Z has had a similar problem at times. I believe it to be related to cold. I hope I am not misspeaking here, but I think it generally clears after things get warmed up.

Ray

Quote:

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Originally Posted by GDeen

Michael,

Try the following link from the Prevost online Technical manuals site for transmissions. It has the procedure for pulling up codes on your shift pad. Also has some trouble shooting info and references to other technical documents that may be of help.

http://prevostparts.volvo.com/techni.../pa1082-07.pdf

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Thanks Gordon! I'm printing the pages at the link you posted right now (32 of them) and am taking them to the bus this morning for reference! Man, I love POG! It's worth every penny of the $500 annual dues that Skiffer charges me! :p

Quote:

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Originally Posted by Ray Davis

Ken Z has had a similar problem at times. I believe it to be related to cold. I hope I am not misspeaking here, but I think it generally clears after things get warmed up.

Ray

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Ray - I desperately hope you are right! :o

Michael,

Maybe this will help; hope so. Skiff only charges me $400/year:D

http://cgi.ebay.com/ebaymotors/ALLIS...item35a5b220f7

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Originally Posted by merle&louise

Michael,

Maybe this will help; hope so. Skiff only charges me $400/year:D

http://cgi.ebay.com/ebaymotors/ALLIS...item35a5b220f7

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Thanks Tuga! Actually my keypad unit looks more like this one: Allison Gen IV Push Button Shifter / Pad

I went back to the bus this morning armed with the info from all the responses to this thread so far. Alas - no luck! I called W.W. Williams (a Detroit/Allison service facilty) in Atlanta and the guy there had me put the tranny into the code reading mode and read him what the screen showed. The good news is that there were no active codes. The bad news is that they can't get road service to me until late this afternoon. My guy at Apalachee RV thinks it may be a relay or solenoid (?) but can't help me further without me bringing the bus to him (and of course, it won't move). I'm not ready for a 60 mile tow, so I'll wait on the W.W. Williams road service and keep my fingers crossed!:rolleyes:

We are keeping our fingers crossed too!!

Michael,

How about if you push "R" , roll your bus few feet back, then "N", and cross your fingers and push "D" and perhaps everything start working again.
Yes, release the Parking Break !

Alek

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Originally Posted by michaeldterry

Thanks Tuga! Actually my keypad unit looks more like this one: Allison Gen IV Push Button Shifter / Pad

I went back to the bus this morning armed with the info from all the responses to this thread so far. Alas - no luck! I called W.W. Williams (a Detroit/Allison service facilty) in Atlanta and the guy there had me put the tranny into the code reading mode and read him what the screen showed. The good news is that there were no active codes. The bad news is that they can't get road service to me until late this afternoon. My guy at Apalachee RV thinks it may be a relay or solenoid (?) but can't help me further without me bringing the bus to him (and of course, it won't move). I'm not ready for a 60 mile tow, so I'll wait on the W.W. Williams road service and keep my fingers crossed!:rolleyes:

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Be cautious and do your homework when buying a part such as this through ebay.

The complete shifter module (the only way Prevost sells them) from Prevo is pt no 571543 $2299.00.

The ebay part no for the keypad is 29541991 with a buy it now price of $145.00.
That may be a good deal if it fits your shifter and is in fact what is giving you trouble, just be sure it will fit your application.
IMHO it is very unlikely that the key pad is at fault.

Also good for everyone reading this to remember that someone of us in POG had the unfortunate experience of getting their shifter module wet by allowing wash water to enter the slide window and soak the pad thereby causing it's untimely demise.



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Good news/bad news... bad news first - The mechanic/technician from W.W. Williams called me this afternoon and said he had researched my symptoms and it sounds like I need a new shifter module. His location did not have one in stock and the closest location that does is in Alabama. He's having the part air freighted in to arrive tomorrow and is having it delivered to his home. When it arrives, he will call me and arrange to come to Woodstock and put it in (he is in Atlanta - about 30 miles from me).

Now the good news - he told me that I could try using the blunt end of a writing pen to push hard on the "D" pad and sometimes that would work as a temporary work-around. I grabbed a pen off my desk, headed to the bus, started and warmed her up, then held my breath and used the pen to push the "D". After poking around (literally "poking it with a stick") a bit, it clicked into gear! Yea! To make sure it wasn't a one time fluke, I shifted to Neutral and then poked "D" with the pen again and it eventually went into gear! Success! Now I was feeling brave to I took her to get fuel and then brought her home to load for the trip to Chattanooga tomorrow. We will decide what to do about the W.W. Williams guy coming out tomorrow depending on what time the part arrives. If it arrives in time to still get us on the road before 4:00PM, we can make our commitment in Chattanooga tomorrow night. If the part arrives too late to get us safely on the road in time, I've decided to take my chances with the "pen poke" work around and have the shifter replaced next week after we return.

Once again, thank you to all our POG buddies who responded with info, advice, and suggestions! You're the best! :D

Well, that's good news. Poke carefully, and I'll bet you're good for at least this trip!

ray

Michael, Today I had a driver for a tour bus company tell me that many of their drivers regularly use a pen to shift gears and for that reason the membrane piece with the letters is replaceable on some newer shift pads instead of replacing the entire module. Sounds as if this may be a common practice with professional drivers.

Michael,

Williams has a place in Acworth, just about 8 miles west of you off Hwy 92 at I-75 and the phone is (678) 574-9251. They suck with buses, I do buy parts there, but maybe they have a pad in stock and since they're so close to you, you could run over there and talk to them.

I was also going to mention that the pads will go bad if they get wet.

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Originally Posted by truk4u

Michael,

Williams has a place in Acworth, just about 8 miles west of you off Hwy 92 at I-75 and the phone is (678) 574-9251. They suck with buses, I do buy parts there, but maybe they have a pad in stock and since they're so close to you, you could run over there and talk to them.

I was also going to mention that the pads will go bad if they get wet.

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Tom - W.W. Williams in Acworth was my first call yesterday, but they couldn't get to me because they were covered up with road service calls. It was them that referred me to the Moreland Ave. location. The tech that I'm working with there did a search for the part and the closest one he found was in Alabama (being air freighted in today). I'm getting ready to call him right now (he gave me his personal cell number) and check to see if he's gotten the part yet and while I'm at it, I'll ask about trying to replace just the pad first to see if that resolves it. Either way - we're leaving town around noon! :D

OK, good, your on the right track. I hesitated to even mention Williams at Acworth and they probably blew you off when you mentioned bus, but they are close enough for a face to face when buying parts. I complained about their lack of bus support while we were at OKC, but didn't expect it to go anywhere.

Just a general comment...don't overlook charter coach operators who have a Prevost fleet. Especially the larger charter companies because they have their own inventories, mechanics and have skilled mechanics. We have one near us that does work on Prevost conversions.

We made it to Chattanooga - no problem! In the RV park now finishing lunch and preparing to go explore a bit before heading to the Tivoli Theatre in the toad tonight to see comedian Ron White. The "pen poke" method of shifting worked like a charm! We even stopped at a Pilot Truck Stop and had Evangeline weighed by individual axle. She was full of fuel, a little over half full of fresh water and grey/black bilge (plus two teen girls, a hot wife, 2 small dogs, and an overweight driver). Also, we carry our golf cart style electric cart in the front bay. The weight ticket shows:

• Steer axle - 15,340 lbs
• Drive axle - 19,580 lb
• Tag axle - 15,060 lbs
• Gross Weight - 49,980 lbs

That's almost 4,000 lbs heavier than I thought she was! How do I find out if this weight is within the acceptable range for my specific coach/chassis? Also, shouldn't the tires be inflated/adjusted depending on the axle weight at each tire position?

Once again, I find myself asking for the POG braintrust to educate me! :o

I'm going to also post this as a new thread to keep these questions from getting lost in the thread creep of this one. I apologize in advance for the duplication!

It is on a data plate, typically located next to the driver's seat. It will list individual axle weight limits and maximum gross weight.

Using those weights you now need to look up the tire pressures for each axle.

http://www.michelintruck.com/micheli...ion-tables.jsp

My guess is you are seriously overweight and should start considering how to bring those weights down to something near the limits for your coach, or recognize that you may have to adjust your driving habits to compensate for the additional stresses those excess weights impose on your air bags, brakes, bearings, etc.

Michael,

For what it's worth, my 1999 XLV shell Prevost Data Plate reads:

Front : 16,500
Drive : 20,400
Tag l: 12,000

GVWR: 48,900

Quote:

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Originally Posted by Jon Wehrenberg

It is on a data plate, typically located next to the driver's seat. It will list individual axle weight limits and maximum gross weight.

Using those weights you now need to look up the tire pressures for each axle.

http://www.michelintruck.com/micheli...ion-tables.jsp

My guess is you are seriously overweight and should start considering how to bring those weights down to something near the limits for your coach, or recognize that you may have to adjust your driving habits to compensate for the additional stresses those excess weights impose on your air bags, brakes, bearings, etc.

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Jon - you were correct with your guess. The data plate shows:

• Steer axle - 14,600 lbs
• Drive axle - 20,400 lbs
• Tag axle - 12,000 lbs
• Gross weight - 47,000 lbs

That puts me almost 3,000 lbs overweight! Ack! :eek:

On tire inflation table. are the weights listed per wheel or per axle? In other words, do I need to divide the numbers by two (for the steer axle and tag axle) and by four (for the drive axle) to get the weight per tire? I'm confuzzled! :confused:

Any ideas on how to shed weight? I'm already on a diet and have lost 18 lbs since December 14th on my way to losing 65 lbs. I don't think I have enough to lose to get Evangeline under weight, though! :rolleyes:

Unfortunately, some of the heaviest items can't be moved: generator, refrigerator, fuel tank, etc. so you will need to be creative with both your amount and placement of personal storage items. You can also opt to carry less than a full tank of fresh water while in transit.

Good luck.....

Michael, when you get a chance have the bus weighed in total. If the area around the scale is not perfectly level it will throw off the individual axle weights significantly. My guess is that your coach is not as heavy as those weights would indicate. If you find that the coach weighs in the 47K range, you could then drop the individual weights proportionally. It is also unusual to have the tag weigh as much as the front axle on a non-slide XLV. If that is accurate you may want to have your ride height checked.

"On tire inflation table. are the weights listed per wheel or per axle? In other words, do I need to divide the numbers by two (for the steer axle and tag axle) and by four (for the drive axle) to get the weight per tire? I'm confuzzled!"

The answer is yes; divide the axle weight you have in actuality by the number of tires on it. And in the case of the drive axle, you need to compare the result against the tire spec for duals, as the weight allowance for a tire mounted as one of a dual is less than as a single. I guess I saw these post thread later on, as I don't see where you state the exact tire model (and make, which I assume is Michelin), size, and rim diameter (I am sure in this case the rim diameter would be 22.5); be sure of what you have, XTA, XZA, XZA-1, and so on, and the size, all exactly as noted on the tire, when you consult the tire table.

If I have mistated anything here, I'm sure be corrected, so watch this thread. Good luck and I hope you can resolve things.

Important.........The tire pressure charts reflect single and dual wheels.

In the case of the tag and steer axles use the inflation pressures specified for single and on the drive axle use the dual wheel inflation pressures.

All are cold pressures, and as a practice I add 5 PSI just to provide a small cushion of added safety should I develop a leak I do not detect right away. If you have a tire pressure sensor system you don't need that extra pressure because you will get an alert before it becomes an issue.

Remember...if you run a tire at 20% less than the specified pressure you have effectively ruined it and driving on it could compromise safety. That is not me talking but the tire manufacturers themselves all stating that.

As to Steve's comment about ride height and the relation between it and any axle weight I do not understand how that impacts axle weights. We only have 3 ride height vales. One centrally mounted for the two front axle air bags, and one on each side (located ahead of the drive wheels in the wheel well) for the left or right rear. When the ride height valves are in the circuit (they are out of the air circuit when in the level low position) the rear ride height valves supply air flow to or remove air from the 3 air bags (2 drive one tag) on their respective sides. All three rear air bags per side have equal air pressure in them regardless of the height adjustment.

Having said that the drive axle air bags are different than the tag air bags on coaches I am familiar with. It is that diference that maintains the weight distribution in the rear between the tag and drive. The tag air bags are generally the same as the front air bags and are slightly greater in diameter (although described as the same) than the drive air bags. The only way to adjust the relationship of weights on our coach rear axles using the leveling / ride system is to use varying size air bags as Prevost has already done.

There has been a misconception in the past that the ride quality on our coaches can be adjusted firmer or softer by adjusting air bag pressures. That is not the case. Using the ride height valves brings our buses to a specified height by adding or exhausting air from the air bags until the bus reaches the set height. The air pressure increases or decreases based on the loads each set of air bags must carry. A bus with a heavy front for example is going to take a lot of air pressure to rise to the correct ride height, or less if the front end is relatively light.

In the case of the 3 rear air bags on each side they all share the exact same pressure because they are all interconnected when thye system is in the road or driving position.

Quote:

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Originally Posted by Kenneth Brewer

I guess I saw these post thread later on, as I don't see where you state the exact tire model (and make, which I assume is Michelin), size, and rim diameter (I am sure in this case the rim diameter would be 22.5); be sure of what you have, XTA, XZA, XZA-1, and so on, and the size, all exactly as noted on the tire, when you consult the tire table.

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Kenneth - actually, I just put on a new set of Firestone FS400's, load rating J.

To make absolutely sure I understand how to use the tire inflation table, is it correct that I would divide the inflation table numbers by two (single) for the steer and tag axles or divide by four (dual) for the drive axle to get the correct recommended PSI per individual tire?

Quote:

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Originally Posted by michaeldterry

Kenneth - actually, I just put on a new set of Firestone FS400's, load rating J.

To make absolutely sure I understand how to use the tire inflation table, is it correct that I would divide the inflation table numbers by two (single) for the steer and tag axles or divide by four (dual) for the drive axle to get the correct recommended PSI per individual tire?

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Michael,

See the excerpt below from the Michelin load and pressure table guide - no dividing by 4....in fact, no dividing at all. Technically, they are saying weigh each axle end and inflate all tires on axle to max end inflation indicated. Dividing by 2 works obviously but is still not the same as weighing each axle end. Rounding up 5 or 10 psi should cover any error by using the total axle weight average rather than weighing each end separately:

In the load and inflation tables, SINGLE means an axle with one tire mounted on each end, while DUAL means an axle with two tires mounted on each end. The loads indicated represent the total weight of an axle end in an RV application. When one axle end weighs more than the other, use the heaviest of the two end weights to determine the unique tire pressure for all tires on the axle. The maximum cold air pressure for each axle may vary, depending on their weights. These tables are applicable for all RV axles, whether or not they are power-driven.

Quote:

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Originally Posted by GDeen

Michael,

See the excerpt below from the Michelin load and pressure table guide - no dividing by 4....in fact, no dividing at all. Technically, they are saying weigh each axle end and inflate all tires on axle to max end inflation indicated. Dividing by 2 works obviously but is still not the same as weighing each axle end. Rounding up 5 or 10 psi should cover any error by using the total axle weight average rather than weighing each end separately:

In the load and inflation tables, SINGLE means an axle with one tire mounted on each end, while DUAL means an axle with two tires mounted on each end. The loads indicated represent the total weight of an axle end in an RV application. When one axle end weighs more than the other, use the heaviest of the two end weights to determine the unique tire pressure for all tires on the axle. The maximum cold air pressure for each axle may vary, depending on their weights. These tables are applicable for all RV axles, whether or not they are power-driven.

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Gordon is completely right, the Michelin tables reflect the whole axle weight (load) and you do not have to divide. The Michelin tables do it for you, no dividing. You have your axle load already, look up the corresponding air pressure and follow the advice about rounding up. Sorry I misled you. Thanks Gordon.

The proper pressures from the Firestone chart for Michael's tag and steer axles is somewhere between 110 and 115 PSI. For the drive the pressures would be around 80 PSI.

http://www.trucktires.com/firestone/...loadTables.pdf

I agree with Steve about rechecking the weights because the tag weight seems unreasonable since his chassis air bags and mine are likely the same and I have a hard time understanding how that much weight can have been shifted onto the tag. I don't doubt the steer axle weight. If that tag axle weight is accurate I would guess at some point oversize air bags have been put on the tag axle and someone needs to check to verify nothing is rubbing. If the weight is correct consider that by having that much weight on the tag turns will be much harder and the tag tires will get excessive scuffing. I would expect to see the tag axle weights in the 11,000 pound range, maybe 12,000.

I hope all new owners are understanding that tire pressures must be adjusted to reflect the axle weights and if the coach has not been weighed it needs to be weighed with full fuel, empty holding tank and full water plus all the personal stuff that is routinely carried.

Michael,

Travel with empty holding tanks and reduce your fresh water to a 1/4 and that will help. Your steer is over because of the golf cart in the front bay.