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so.. reading through another thread about speedometer and odometer stuff i was searching around on google and i was reading that on our trucks if your speedo is off vs your tire size it will greatly effect the way your computer attacks shift points..

so my question is if I calibrated my speedo to match my 35's will my shift points improve or is all this smoke up my tail pipe?:confused013:
 

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yes i have 32s and my truck would roll in to second and shift to soon so i adjusted the tire size w/ my bully dog and now it shifts alot beter ,but it still shuffles between first and second under light throttle
 

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yeah that 1-2 gear searching is exactly what my stock trans did before it chit the bed.. my ats doesnt do that
 

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My experience is yes it makes a difference. The transmission will shift at the same ECM calculated mph with the bigger or smaller tires. If the ABS Revs Per Mile is not correct then the mph will not be accurate. Not saying that is good, bad or ugly. It is just what I have experienced with different size tires and ECM programmed right and not programmed right.
 

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im gonna go w/ a local performance shop to do my rebuild upgraded clutches,bands ,input shaft ,v.b. and torque converter
 

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My experience is yes it makes a difference. The transmission will shift at the same ECM calculated mph with the bigger or smaller tires. If the ABS Revs Per Mile is not correct then the mph will not be accurate. Not saying that is good, bad or ugly. It is just what I have experienced with different size tires and ECM programmed right and not programmed right.
Thats kinda what I was thinking made sense.. it does change the shift point but to the tiniest percent who is to say that its a bad thing but probably wouldnt hurt anything either if I corrected the speedo..

I see your from houston, Im actually in fort worth right now for work.. this is my first time in texas and its not too bad... i just miss the mountain scenery a little bit :lol4:
 

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Thats kinda what I was thinking made sense.. it does change the shift point but to the tiniest percent who is to say that its a bad thing but probably wouldnt hurt anything either if I corrected the speedo..

I see your from houston, Im actually in fort worth right now for work.. this is my first time in texas and its not too bad... i just miss the mountain scenery a little bit :lol4:
We have mountains in Texas you just have to drive about 800 miles from there to see them. :hehe: :hehe:

Hill Country around Austin is nice, but does not compare with true mountain scenary.
 

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We have mountains in Texas you just have to drive about 800 miles from there to see them. :hehe: :hehe:

Hill Country around Austin is nice, but does not compare with true mountain scenary.

:hehe::hehe: Mountains in texas..... ???
I never even thought of this, I never recalibrated the comp when I went to 33's speed stayed the same so I figured it was fine.... this may explain some of my complaints with my tranny lately
 

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I bought my truck used with a diablo predator on it. The speedo was off 3mph @ 60. Played with tire size settings until I got speedo to match gps. Shift points changed slightly. TC lockup seems less pronounced than before.
 

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With the edge juice/attitude; you can enter in your larger tire size and it will give you the corrected speed. Will this inturn tell the ECM and get the tranny shiftin right again??
 

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No. Itll only show the adjusted speed on the Juice; factory speedo will still be off
 

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Thats kinda what I was thinking made sense.. it does change the shift point but to the tiniest percent who is to say that its a bad thing but probably wouldnt hurt anything either if I corrected the speedo..

I see your from houston, Im actually in fort worth right now for work.. this is my first time in texas and its not too bad... i just miss the mountain scenery a little bit :lol4:
Welcome to the area. I'm just out West of Fort Worth.
 
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