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  1. #1

    Default Biggest tire without gearing

    Hey I have my stock 2006 z71 on 9 inches of lift on 38x15.50x 20 I'm about to gear it but wondering if I go with a smaller tire what should I get so I don't have to gear it. THANK YOU

  2. #2


    As I understand it, the goal in selecting a final drive ratio/tire size is to pick the ratio/tire combination that will allow the engine to run at ~2000 rpm in OD at ~60 mph. What gear ratio is currently installed? Which tranny (and what is it's OD ratio, if you know)? What engine speed are you currently running at 60 in OD (if automatic, is it shifting into 4th gear)?
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  3. #3


    i wanna see some pics of that!!
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  4. #4
    finalday7's Avatar
    Join Date
    Oct 2007
    Sayward, B.C Canada


    Unless your running a minimum of 4.56 then I'd recommend that you regear. With 9"'s of lft I wouldn't go smaller then 37's. If you keep your current tires I'd probly go with some 4.88's. By the sounds of it your still running stock gears, probly 3.73. Trust me, your going to want to regear or you'll be sorry later.

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  5. #5


    your running stock gears on 38's??? I thought the rule of thumb was don't go over 35's on stock gears. 35's would look weird though with 9 inches of lift. What gears do you have now?
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  6. #6

    Default ratio calculator

    go to the have a calculator on the site

  7. #7


    Ya I am running stock gears now but it is just temporary I'm about to install my 4.88's and I guess will keep the 38" tires I will put pictures up soon thanks

  8. #8
    finalday7's Avatar
    Join Date
    Oct 2007
    Sayward, B.C Canada


    No problem and can't wait for the pictures.

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