Truck Guys Allison Question????

[JIA's Dad]

I bought this truck last Tuesday. It's a 2004 GMC Sierra Duramax 4x4.





My problem is the truck came with two tunes on it, set up on a flip switch. When I flip the switch to the stronger tune, when running 60-70 mph and flooring it, the transmission down shifts causing an engine code/ light and showing range shift limited (stuck in third gear).

The question "Does anyone know how to eliminate this problem without buying a Sun Coast or some other transmission?

[NorCal 2500HD]

Im guessing you bought it from a private party? Sounds like the transmission is going into limp mode. Do you know what programmer is in it? HP Ratings? The allisons are great, but once you start throwing some power to them the clutch packs start to go ( usually C1-C3 ).
Anyway you can get the codes? That will help out a bunch.
P07xx Trans
P08xx Trans
P09xx Trans
P17xx Trans
P18xx Trans
P19xx Trans
If the previous owner liked to roll some coal and threw a bunch of extra HP to a stock tranny, you might just have to get a rebuild.
Check out Dieselplace.com. TONS of info on their as well.
Nice Truck!!!

[ROSS]

yep your tranny is going into limp mode.

is the second programmer a "Crazy Larry"? if so, get rid of it. thats to much power for the stock tranny.

if you want to keep both programmers and you have some extra coin laying around, rebuild the tranny with beefer internals and stronger clutch pads. but itll cost you.

good looking truck though

[shelby]

I thought allison tranmissions were supposed to be the most badass tranny out there,yet it seems like a little chip is to much hp for it?(correct me if im wrong)

[JasonInAugusta]

Originally Posted by shelby

I thought allison tranmissions were supposed to be the most badass tranny out there,yet it seems like a little chip is to much hp for it?(correct me if im wrong)

The first tune is above stock, the 2nd is equivalent to "Holy shit! What did I do?"

He says he can flip the switch and the entire truck will rumble and shake - shit's ready to go.

Dad, nice truck!


(Except for those wheels. )



If you'd stop trying to put dents in the floorpan with the throttle pedal your transmission would be fine.

[goobs]

Originally Posted by shelby

I thought allison tranmissions were supposed to be the most badass tranny out there,yet it seems like a little chip is to much hp for it?(correct me if im wrong)

you're wrong.
they are the best. they can handle about 500hp. stock before they start to wear out, 'course a lot has to do with the way you drive and what mods you've done. but compared to ford and dodge stock tansmissions, allisons are the best.

[JIA's Dad]

Since this truck was sold as a repo, I was not given any onfo on the previous owner. Therefore I was not able to talk to him to ask what had been done to/with the truck. I just got a very reasonable price and excellent financing. I couldn't turn down the deal.

The motor is the stock LLY. Not a bolt on it has been turned. That I can tell.

I'm afraid that I have a problem with both. My foot, I'm an old gasser/geezer who likes to slam it to the floor and hold on. And the higher tune does have more fuel in put and more HP. Not sure yet on how much HP but it will lite the tires UP!!!! Might do a dyno run or two soon, as long as the wife doesn't find out. But I need to know what I have under the foot.
I am also curious as to the 1/4 mile times.

Yes it is going into limp mode, this has happened 3 times under hard foot pressure, usually when it kicks down to lower gears on acceleration.

So so far I'm looking at a rebuild with stronger internals,(Sun Coast) any other ideas on the tranny problem. I thought we had a bunch of mechanics on here, with all the racing going on here. Or is there no other solution.

I had heard that the Allison was able to be tuned to a point as far as shifting points. Is this true......

The truck is fine as long as I keep my foot out of it. Very hard for me to do!!!!

[megacabcummins]

Originally Posted by JIA's Dad

I am also curious as to the 1/4 mile times.

This should give you an idea of what it is capable of.... My buddy Rob doin his thing... truck weighs just over 6000lbs....

http://www.youtube.com/watch?v=ZyzETNnFjvA

[crash]

The Alison is a bad as trans and we have only had a few drop dead or have any major issues. But with that said in stock form they even have there limits and sounds like you are exceeding them. We have a couple customers who have had them built to handle whatever can be thrown at them and they do.

You need to dig into your rig and see what you have for modules and go from there plus see what codes are present as there are mnay ways the trans will go into limp mode.

[megacabcummins]

You might look into at least a better torque converter, valve body... you know the drill. Find a good transmission shop that's near you, doesn't have to be suncoast and tell them what you want to do with the truck. Spend the money on the transmission, take it out once, have it built, and put it back in once. Also call Beans Diesel, City Diesel, or Blakes Diesel Performance just to name a few in your area. My buddy who is a race director for the NHRDA also lives near you, I'll see if he knows who you should contact. I would also jump over to http://www.competitiondiesel.com/forums

[dkf]

Originally Posted by goobs

you're wrong.
they are the best. they can handle about 500hp. stock before they start to wear out, 'course a lot has to do with the way you drive and what mods you've done. but compared to ford and dodge stock tansmissions, allisons are the best.

The 5R110 in the Fords hold up a little better than the Allison with higher power levels with the proper shift and lockup strategies.(Stock trans vs Stock trans) Go do some research and see for yourself. The allison will hold a good amount of power with the proper tuning however. People think the Allison is the best tranny in the world because its used in medium duty and larger trucks and equipment. Just because a company is well known with a supposibly good rep doesn't me the product doesn't have faults.

Certain companies are better at tuning than others. Some tuning companies put out some real junk which is hard on the engine and harder on the trans. Best bet is to get a forum with a lot of Duramax owners and see what they are running and the pros and cons. A lot of them will have already spent the cash finding out what works best.

[BigBaller]

John Kennedy of Kennedy Diesel. In Loyal Wisconsin. Look him up. He knows his sh!t.

[HomerJ]

Warren, give Richie a call. I don't have his number, but I'm sure one of the boys at Coyote does. Supposedly Richie is THE man when it comes to transmissions..

[shelby]

So the most badass tranny out there can only handle 500hp?WTH...thats weak!

[BigBaller]

Originally Posted by shelby

So the most badass tranny out there can only handle 500hp?WTH...thats weak!

Your are a dumbass. Yes, I said it.

What you don't understand is that even with 500 hp, the torque is probably upwards of 900. THAT is a TON of torque and a LOT of horsepower. Do you even know what 500hp feels like?

Here's one for ya Character, what do you drive?....And the rule is pictures or your a liar.

[BigBaller]

Shelby, nevermind. I just checked out your profile, you aren't old enough to drive.

[shelby]

Yes you are correct i dont drive becuase im not old enough to lagally.

Yes,i have expeirenced being in a car with 540hp.

You are also right,i wasn't thinking about the torque that was being produced with with a diesel that should produce more torque than hp,and torque is the main enemy against breaking parts,so sorry you chevy lover anal asshole.

[country_crawler]

Originally Posted by shelby

Yes you are correct i dont drive becuase im not old enough to lagally.

Yes,i have expeirenced being in a car with 540hp.

You are also right,i wasn't thinking about the torque that was being produced with with a diesel that should produce more torque than hp,and torque is the main enemy against breaking parts,so sorry you chevy lover anal asshole.

If you want to get in a real truck. Family company has a 1989 Kenworth W900 Flat top, Cummins, 650HP, Straight stacks. Man it rolls the coal. I don't know how much Torque it has but let me tell you, she trugs along perty good.


Anyway nice truck, you need to go slap your son for buying a ford.

[shelby]

Ive also got to ride in a 72' chevelle with a stock duramax in it,all it had was a chip and it ran high 11's in the 1/4,it pulled pretty good too.

[dezfan]

Isn't it time for Sponge Bob, or iCarly, or something? Run along and play...........