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Discussion Starter #1
With my new bfg 285/75/16 my milage is off 5mph or so and i have read the dealer can fix this. Will the dealer flag my truck for drivetrain warranty revocation. I can get the bully dog to fix this problem but i dont feel like i need the power nor do i want to chance screwing up the tranny even on economy mode. Any input would help guys!!! thanks in advance
 

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FWIW, I just flew to San Francisco and purchased an '04 LB7 with 285/75's. On the drive back to UT, I compared the MPH on the speedo with my GPS. It consistantly read 6% slower than my GPS. When I was going 50MPH the GPS read 53MPH. The 285's have a 7.3% greater diameter than the stock tires, so this is a pretty close finding.

Steve
St. George, UT
04 CC LT, LB7, Centerlines, Leer Shell, Solaire Sunroof
 

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No, the dealer cant fix it. Even if they say they can, they cant. They can calibrate your ABS/EBCM/EHCU for the bigger tires, but not the speedo. You'll need a programmer or tuner to fix it... sorry.

Ben
 

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>They can calibrate your ABS/EBCM/EHCU for the bigger tires

ABS I understand, but EBCM and EHCU I don't. What do they do?

Steve
 

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EBCM=electronic brake control module
EHCU=electro-hydraulic control unit

basically they are both just additional modules/computers/parts of the ABS system. ;)

Ben
 

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OK, thanks Ben. I was hoping they had something to do with the DIC.

Steve
St. George, UT
 

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285's

I also want to add 285's to my '06 LBZ, will these cause any problems w/tranny or codes etc? I plan on getting the BD for the speedo cal.
Thanks
 

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Discussion Starter #8
no codes and i havent noticed a significant change in the shifts or trany temp
 
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