Allison shifting - Montana Owners Club

bigred715 · 01-23-2009, 12:29 PM

Have had a problem recently with the truck not coming out of park and into gear. Own a 2007 Classic 3500 Chevy. After driving a distance and shutting off motor, it will not go out of park. I have to shut off motor, put into neutral, start and then it will shift to drive. If it sits long enough to cool down it shifts fine, but not immediately after turning off. They checked it several months ago at the dealership and did something with computer but now it is doing it again.

SlickWillie · 01-23-2009, 01:07 PM

You getting any info on the DIC? Range Shift Inhibited or such?

HughM · 01-23-2009, 02:40 PM

Take it to a AutoZone or similar and get it scanned for a code that was tripped. If it shows a code then they can tell you the problem. AutoZone will do it for free.
Hugh

rogue · 01-23-2009, 04:26 PM

Not sure if its your problem, but I had the engine check light come on. Had it checked and found there is a switch in the tranny that tells if its in Park or Neutral. Mine shorted out and could not use the cruise and had the check engine light on. They had to replace the Switch, O ring and gasket. It was had shifting out of park before they replaced the Switch.
Bob

Glenn and Lorraine · 01-23-2009, 10:20 PM

Don't know your problem but I do know how to get it diagnosed and corrected. That 07 is still under "warranty" and the only place I would take it is your local Chevy dealer.

SlickWillie · 01-24-2009, 01:38 AM

Glenn, I think he has been that route. Perhaps he is trying to get ideas on what might be causing the problem. Apparently the dealer didn't fix it, just reset something in the computer.

I think what Rogue is talking about is the NSBU switch, which tells the computer what gear the shifter is in. The dealer changed that switch on my D/A, but it did no good. Another dealer, in Kingsville, TX, found a switch block on the ignition switch was faulty. This switch was sending low voltage to the transmission, which was shutting down to protect itself.

I have a 2004 GMC. The NSBU switch was covered under the emissions warranty (don't ask me why), but I ended up about 500 bucks out for the ignition switch contacts.

Delaine and Lindy · 01-24-2009, 08:48 AM

Just opinion but I would take it to a Allison Transmission shop. Don't know if this is true now but I was told that GM has no Certified Allison Transmission Tech's. I had a code on our Chevy Kodiak 4500 and the Chevy dealership in Mission Texas had me take it to the Allison shop. While there the Allison Tech hooked the Transmission up to a Computer and run a complete check and installed all new up dates. I even got to watch the computer screen while this was being done very interesting. If its a 2007 Allsion its under warranty. Next time I have a Transmission issue I will request a Allison Trans Tech. However the problem I had was really a wire that had been knocked loose in the fuse box, while Circuit City was installing a XM radio which thru a Transmission code? The Circuit City issue want be discussed, don't need my B/P going up. GBY...

SlickWillie · 01-24-2009, 08:59 AM

Quote:

quote:Originally posted by Delaine and Lindy

Just opinion but I would take it to a Allison Transmission shop. Don't know if this is true now but I was told that GM has no Certified Allison Transmission Tech's. I had a code on our Chevy Kodiak 4500 and the Chevy dealership in Mission Texas had me take it to the Allison shop. While there the Allison Tech hooked the Transmission up to a Computer and run a complete check and installed all new up dates. I even got to watch the computer screen while this was being done very interesting. If its a 2007 Allsion its under warranty. Next time I have a Transmission issue I will request a Allison Trans Tech. However the problem I had was really a wire that had been knocked loose in the fuse box, while Circuit City was installing a XM radio which thru a Transmission code? The Circuit City issue want be discussed, don't need my B/P going up. GBY...

I'm surprised they worked on the 4500. IIRC, it has the same tranny as the 2500 and 3500 HD. I used to get my filters from the Allison shop in Longview, TX. They couldn't even look up the part numbers for me. Said they had no info on them. They did have the best price on filters though.

bigred715 · 01-24-2009, 10:30 AM

Thanks for all the responses. When I take it in for service I will ask them about some of the things suggested. You would think someone would be certified to work on Allison transmissions at the dealership I bought it from. They sell a lot of Chevy products. Thanks again, Jeff

SlickWillie · 01-24-2009, 10:45 AM

Quote:

quote:Originally posted by bigred715

Thanks for all the responses. When I take it in for service I will ask them about some of the things suggested. You would think someone would be certified to work on Allison transmissions at the dealership I bought it from. They sell a lot of Chevy products. Thanks again, Jeff

You never know. I had the first service done in Brownsville, TX (NSBU switch). When the mechanic finished the job, he proceeded to tell me it was the first Allison he had ever worked on. When it didn't fix it, he told me to just drive it and maybe it would get better. HA!

At the dealer in Kingsville, they had a good Allison transmission mechanic. He seemed to think they had just failed to clear the trouble codes, but when I drove it and came back, it didn't take him long to find the problem. Good luck.

Delaine and Lindy · 01-25-2009, 01:29 PM

One of the issues that was a surprise to me was when I went to a Chevy dealership and was told they weren't authorized to work on a 4500 series Truck. I was then told to look inside the info packet (owners manual) and there would a list of GM dealerships that were authorized to repair or work on a 4500 series Truck. The Transmissions were the same in 2006 as the 3500HDs. The dealership was in Clarksville Tn. I had to take the Chevy 4500 to a GMC dealership in Clarksville, Tn. Now that was different. To work on a Allision transmissions the Tech has to be a Allison certified Tech or thats what I was told in Mission Texas Chevy dealer. But they can change a fuel filter? What a deal. Loved the Chevy 4500 was the best riding Truck I have owned. GBY.....

SlickWillie · 01-25-2009, 01:46 PM

Quote:

quote:Originally posted by Delaine and Lindy

One of the issues that was a surprise to me was when I went to a Chevy dealership and was told they weren't authorized to work on a 4500 series Truck. I was then told to look inside the info packet (owners manual) and there would a list of GM dealerships that were authorized to repair or work on a 4500 series Truck. The Transmissions were the same in 2006 as the 3500HDs. The dealership was in Clarksville Tn. I had to take the Chevy 4500 to a GMC dealership in Clarksville, Tn. Now that was different. To work on a Allision transmissions the Tech has to be a Allison certified Tech or thats what I was told in Mission Texas Chevy dealer. But they can change a fuel filter? What a deal. Loved the Chevy 4500 was the best riding Truck I have owned. GBY.....

Never gave it much thought, but not all dealers sell the 4500 trucks. Perhaps they have to be a fleet dealer. I know Peter's Chevy in Longview, TX sell fleet. They also usually have some 4500s in stock. At least they did a couple years ago. Seems GM sold the 4500 line up to someone else?

Clyde n Deb · 01-25-2009, 02:29 PM

Chevrolet and GMC dealers have to be setup and approved as "heavy duty" dealers to sell and service models beginning with the 4500 series.

Many dealers don't have this level of stature.

I know because one of my customers has to take his tow truck 100 miles past 3 Chevy dealers to Denver to get it looked at if he wants warranty to apply.

MacDR50 · 01-26-2009, 01:13 AM

This morning I started my truck remotely to let it warm up. I put in my key after about 5 minutes and proceeded to take out the trash. When I got in to drive away it wouldn't shift out of park. I shut it off and restarted and no problem. I suspect that the lock-in-park feature of the remote start was the problem. It was damp yesterday and went down to -15C overnight. It may never happen again or it may be a sign that a sensor is being affected by cold/moisture.

Delaine and Lindy · 01-26-2009, 02:31 AM

There was a time a few months back that Chyrsler was going to buy the MDT line 4500's and up but the deal didn't happen. Now the Chevy Kodiak 4500 we owned wasn't the regular Cab and Chassis type our 4500 was upgraded in Elkhart Ind. at Chariot Vans. The upgrade was MSRP at $26,000 didn't pay that much. As I have said it was the best riding Truck we have owned. All Air ride suspension, seats etc. I miss that Truck. GBY...

SlickWillie · 01-26-2009, 03:10 AM

These trucks can do strange things, then never do it again. I would blame it on glitches in the programming. The door chime and other chimes sound through the driver's door speaker. Mine have a mind of their own. Sometimes it works, sometimes it doesn't.

Here's an article on the Kodiak trucks. Trucktrend. I don't know if the deal was finalized or not, but I had read somewhere that International was buying the line.

jjackflash · 01-26-2009, 07:07 AM

Quote:

quote:Originally posted by MacDR50

This morning I started my truck remotely to let it warm up. I put in my key after about 5 minutes and proceeded to take out the trash. When I got in to drive away it wouldn't shift out of park. I shut it off and restarted and no problem. I suspect that the lock-in-park feature of the remote start was the problem. It was damp yesterday and went down to -15C overnight. It may never happen again or it may be a sign that a sensor is being affected by cold/moisture.

I've done this several times. I'll start with the remote and than open the door and slide the key in the ignition than go do something else. When I get back I try to put it in gear and it won't go,I than realize I forgot to actually turn the key on when I put it in,Duh!
Jack

MacDR50 · 02-19-2009, 08:32 AM

My problem resolved. It seems that the Ally tranny hates to be parked on even the slightest hill. I have duplicated the problem at least 3 times by parking on a slight rise. The last time on less than 8 inches of snow built up by a curb. What I took to be a gearshift lock-up was actually resistance to come out of park due to the pressure on the parking pin (pall). I have never driven anything that is this unforgiving. I guess it is back to my manual tranny days of setting the parking brake before taking it out of gear.

flstf · 02-19-2009, 10:46 AM

I am glad the problem resolved itself, but just wanted to throw in a couple of cents....Glenn nailed the warrenty recommendation with a dealer because they can read the codes. For what its worth Autozone or any other parts store cannot "see" the transmission codes. Their scanners read engine codes, not transmissions, body modules, ABS, airbags, etc. All ECMs store these codes, but few scanners have the capability to read (example, OTC's genisys system will). I, like most, cant stand someone to work on my vehicles and any tool available that will help troubleshoot the problem I want in my tool kit.
Again, glad it the problem fixed itself. A couple of years ago my DW drove her tahoe to the store in 4 low....she was convinced the transmission was out, I pushed the button and "fixed" the problem...told her a fuse was blown, must have been my fault.
take care,
Joe

TLightning · 02-19-2009, 01:10 PM

Quote:

quote:Originally posted by MacDR50

My problem resolved. It seems that the Ally tranny hates to be parked on even the slightest hill. I have duplicated the problem at least 3 times by parking on a slight rise. The last time on less than 8 inches of snow built up by a curb. What I took to be a gearshift lock-up was actually resistance to come out of park due to the pressure on the parking pin (pall). I have never driven anything that is this unforgiving. I guess it is back to my manual tranny days of setting the parking brake before taking it out of gear.

I had an old time mechanic tell me one time to never put any transmission into Park with any weight/pressure on it. He said to set the parking brake first, then put the trans in neutral to take all the pressure off, then go to Park.

This paid off a few years ago. I had my truck nosed into a spot with the brake/trans set as above. A kid, in the process of stealing a huge old 70 or 80s Pontiac, went wheeling around a corner, hooked the bumper of my truck with his bumper, and yanked the truck out of the parking place. My truck ended up 90 degrees to the way it was facing when parked and about 30' down the road. Never hurt a thing, the parking brake was set firmly, so the kid just drug the truck's rear wheels. Had the parking brake not been set, it would have broken the pin and done a job on the transmission.

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