Speedo Adjustment with 37's

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Speedo Adjustment with 37's

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Hummer Forums >> Brand Reviews >> Tire and Wheel >> Speedo Adjustment with 37's

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Speedo Adjustment with 37's - 3/18/2007 7:43:46 PM

07HummerH3

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Sorry if this is a silly question as I can already imagine the onslaught - can (if so, where) can I get the speedometer/odometer recalibrated if I have 37's put on? I'm currently running 35's

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RE: Speedo Adjustment with 37's - 3/18/2007 8:05:23 PM

littlehummerboy

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Not a stupid question. Obviously, your dealer can do it, but not sure what they would charge. Keep in mind, that whatever they DO charge, if you deduct that from what PCMforless charges(as they can change the speedo as well) you might want to spend a little more to get the PCM upgrade. In other words, if your dealer charges $75 do reprogram speedo only for you, that means you could get pcmforless to do it as well, but only pay $125 extra for a custom PCM tuning as well. That's off their regular $199 price. If they have a special on, the difference would even be less.

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RE: Speedo Adjustment with 37's - 3/18/2007 8:28:22 PM

Gunner_45

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From: North Central Texas
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I'm just curious if there is a limit on tire diameter within the PCM's programming.

It seems like I've heard that 33 is the biggest GM would/could do.

Has PCMFL got a way around this? They do 35's right?

< Message edited by Gunner_45 -- 3/18/2007 8:31:32 PM >

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RE: Speedo Adjustment with 37's - 3/19/2007 12:48:49 AM

importkiller

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you can get the speedo calibration box, I believe super lift or skyjacker makes it. It wires between the tranny and the pcm and you adust it with a small set screw until your speed is true. There is also a switch on it that you can switch back to stock if needed. I have one on my dodge and it works great, before hooking it up my speedo would read 60 and I my gps said 82. install is very easy, especially for me...I supplied the beer and my friend installed it, was a total of a 4 beer install

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RE: Speedo Adjustment with 37's - 3/19/2007 4:06:49 AM

Crash

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This may sound like a silly question, but what lift kit are you planning on using so you can stuff 37's under your truck..??

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RE: Speedo Adjustment with 37's - 3/19/2007 7:59:08 AM

07HummerH3

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quote:

ORIGINAL: Crash

This may sound like a silly question, but what lift kit are you planning on using so you can stuff 37's under your truck..??

I'm a Dumb A$$ having a total Brain Fart; I have 33's and want to put on 35's

LittleHummerBoy - Great suggestion, I'll definitely go the PCM route. Thanks

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07 H3: Slate Blue Metallic(a) w/ Tan interior, Lux & Adv Pkgs, 35" MTZ's, Gibson SS Split Rear Exhaust, TrueFlow CAI, Truxxx Lift, Nav System, Monsoon Stereo/CD, SIRIUS, Sunroof, Chrome Brush Guard, Chrome Mini-Grille, Tow Pkg, Silverstars, Roof Rails

(in reply to Crash)

Post #: 6

RE: Speedo Adjustment with 37's - 3/19/2007 8:13:46 AM

dilo2001gt