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Discussion Starter #1
I read on a post that going up to 285/75/16 can change how your transmission shifts and your grade changes (downhill) when tow/haul is on. I was wondering if......#1, my bully dog kit has a section where I can change my tire size and does that aid in the problem with the transmission, or just the speedo?

#2, Is the difference in transmission function really that different that you would need to make any modifications?

Thanks.
 

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your transmission shift points are determined on several different variables.... one of those is speed. if said value is inaccurate, then your transmission won't shift properly, because you will be going x miles an hour when it thinks you are doing y miles an hour.

if you fix the speedo, it fixes the transmission.... because the transmission relies on the speedo.
 

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I have 285/75-16's and my tire size corrected and mine shifts fine. It shifted fine without correcting tire size also, speedo was just off.
 

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google what a valve body and a solenoid pack is in a transmission.

if your speed is off, your shift points/firmness is off

it defies physics if it stays the same
 

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Discussion Starter #6
Thanks for the replies. I will have to go through my Bullydog and see what other settings are in there, but I did see the "change tire size" option before. I am going to turn the torsion bars up a "tiny bit" for the leveled look. I read that huge post on torsion lifts, so I am confident that with minimal adjustment I can get the look I want and run the 285's. I was just a little hesitant with the whole tire size/shift points mess.

Thanks for all the information.....very good to know.
 

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i basically have the same setup. although i have a different torque converter and if i am going slow say 45 mph and it has already shifted into 5th gear the TQ locks up incredibly hard. I wonder if it has to do with tire size/ speedo??
 

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This is news to me. Someone please break this one down barney style for me...
 
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