Can or Will your local GM Dealer change the tire size parameters in your vehicle's computer to accommodate going from stock LT 245/75/16 to larger LT 285/75/16 and will it affect the warranty coverage ? Has anybody gone through this with your dealer ?

Thanks for your response !

Hi this is Macksmom's husband :) I have been a GMC mechanic for years... got bored tonight so logged in here :)

If you have a 2500HD with an allison transmission, you CANNOT change the parameters, it's a software issue with the tansmission programming.

Other transmissions can be set up to accommodate different tire sizes although you may be charged.

It will not be covered under warranty because you are making changes to the factory settings of the truck.

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nauticalstar420 agrees: You should create an account. We can always use advice from a good mechanic :)

Hey girl :) Yeah I am sitting here while he gets his "fix" on cars lol... I told him how great this site was and to get his own account... so I'm sure he will :)

Comments on this post
nauticalstar420 agrees: You should create an account. We can always use advice from a good mechanic :)

Hey girl :) Yeah I am sitting here while he gets his "fix" on cars lol...I told him how great this site was and to get his own account...so I'm sure he will :)

LOL that's funny. Of course it all sounds like gibberish to me, that's why I know he has to know what he's talking about.. lol. :p

LOL thats funny. Of course it all sounds like gibberish to me, thats why i know he has to know what he's talking about..lol. :p

Yep... he got bored, and knows I am addicted to this site... so he was like "hey check out car questions" lol... I know NOTHING about cars... then he started answering every friggin question that had to do with cars... I told him he needed to create his own account so people don't start asking me about cars! LOL

Yes the spedo can be recalabrated by the dealer and also form some of the aftermarket programers. I have done this both ways ten minut task on the tool.