Just lifted 2015 1500 and added 35s, reprogramming needed?

stontr01 · September 29, 2015

Hey everyone,

I just bought a 2015 1500 Sierra, got it lifted with a 6" BDS and added 35" Mickey Thompson ATZ P3s. This morning i had an appointment at local GMC dealer to get the computer reprogrammed to account for 35" tires. After 45 minutes of waiting they said GM doesn't offer a comparable size software download so they couldn't help me.

I know that my speedometer is off and I'm thinking my MPGs are off too. But I'm curious if not getting this reprogrammed will cause other damage? Shift points? ABS system?

If you have reprogrammed your truck for bigger tires, what aftermarket programmer would you recommend, or is this needed?

Any advice or insight would help, Thank you!

fondupot · September 29, 2015

If you want the down and dirty version, a Diablo handheld will do what you want.

But if you aren't afraid to do custom tune, talk to Blackbear Performance. You won't be disappointed.

stontr01 · September 29, 2015

Thanks for the response, Im a bit of a rookie with tuning, changing tire settings with the programmer seems straight forward, I'm assuming custom tuning allows more configuration options for shift points, performance, etc?

How did the Blackbear tune impact your truck?

fondupot · September 30, 2015

Thanks for the response, Im a bit of a rookie with tuning, changing tire settings with the programmer seems straight forward, I'm assuming custom tuning allows more configuration options for shift points, performance, etc?

How did the Blackbear tune impact your truck?

Yea, the handheld would be pretty easy.

Blackbear also sends you a handheld device to read your stock tune and install their tunes.

I am running a 93 octane performance tune, and it really wakes the truck up. They get rid of that "dead" pedal feeling where you hit the gas and it takes a second to react. They also tune the transmission and make it shift a lot better.

This is the third vehicle I have had tuned by Blackbear.

arkenzo · September 30, 2015

I know that my speedometer is off and I'm thinking my MPGs are off too. But I'm curious if not getting this reprogrammed will cause other damage? Shift points? ABS system?

I'm curious to this as well.

stontr01 · September 30, 2015

stontr01, on 29 Sept 2015 - 10:07 AM, said:

I know that my speedometer is off and I'm thinking my MPGs are off too. But I'm curious if not getting this reprogrammed will cause other damage? Shift points? ABS system?

I'm curious to this as well.

Anybody know what other impacts there may be on with the truck with NOT adjusting software to acknowledge bigger tire and wheel size?

thanks,

TJay74 · September 30, 2015

It will throw the ABS, TCS, Stabilitrak off, shift points in the transmission will be off as well since the speed is not going to be accurate. Tires are moving slower than actual speed now.

Hypertech makes something to change tire size as well.

stontr01 · October 1, 2015

It will throw the ABS, TCS, Stabilitrak off, shift points in the transmission will be off as well since the speed is not going to be accurate. Tires are moving slower than actual speed now.

Hypertech makes something to change tire size as well.

I take it your describing this product: http://www.hypertech-inc.com/products-speedometer-calibrator.aspx

Will this also change shift point, ABS, etc. for a 8 speed transmission?

thanks,

stontr01 · October 2, 2015

are there any risks or possible damages that could result from tuning or using a bullydog or hypertech?

Roader · October 2, 2015

I know lot of people get those but I prefer to get an actual tune from a tuner. I've never used black ear since I dont like doing email tunes but most people seem to like them. Look up any LSx shop local to you and they should be able to do it as well

sailor9908 · October 4, 2015

my dealership used the hyper tech speedometer calibrator to correct my truck after getting the lift/tires installed. nice this is this particular setup can be upgraded to hypertechs max power programmer by just calling customer service.

calgator73 · October 4, 2015

Everyone else makes great points... Consider a ring and pinion swap as well.

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sailor9908 · October 4, 2015

Everyone else makes great points... Consider a ring and pinion swap as well.

Sent from my LGLS990 using Tapatalk

Ring and pinon are next in line on my shopping list, hahaha

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calgator73 · October 4, 2015

Lol... Price of going with taller tires

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azarj10 · October 11, 2015

What in the world is GM talking about? The calibration tool was a little pricy, but calibrated my setup perfectly. Even followed my buddy to make sure speeds were on point. I have the same setup as you do except 35" K02's.

I believe this is what I bought with my setup.

http://www.hypertech-inc.com/products-speedometer-calibrator.aspx