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3.07gears and 38's?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by bigjblazer, May 3, 2002.

  1. bigjblazer

    bigjblazer Registered Member

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    3.07gears and 38\'s?

    what would happen if i had 38's and stock 3.07 gears, would they just break, or yield really terrible performance? Thanks
     
  2. dysphemism

    dysphemism 1/2 ton status

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    Re: 3.07gears and 38\'s?

    good question. Id imagine it would bog like crazy.
     
  3. txbluethunder

    txbluethunder 1/2 ton status

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    Re: 3.07gears and 38\'s?

    if you have an auto it would prob blow up! standard, it would prob just be really slow.
     
  4. Pure Insanity

    Pure Insanity 1/2 ton status

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    Re: 3.07gears and 38\'s?

    Well its not too good for it. I have 3.07 or.08s in mine w/ 38s. I need to get the 4.88s in soon.

    There is a similar thread in the garage BTW.
     
  5. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Re: 3.07gears and 38\'s?

    Actually, higher gears are stronger (due to higher tooth count).

    My buddy had a D44/12 bolt combo that survived to 44" tires. They had 2.73 gears.
     
  6. mike reeh

    mike reeh 1/2 ton status

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    Re: 3.07gears and 38\'s?

    good call. this is true

    i think it will survive it just wont be very peppy.. in low range you should be able to get around fine. it goes without saying that its not the ideal gearing for those tires /forums/images/icons/smile.gif
     
  7. morphed86k10

    morphed86k10 1/2 ton status

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    Re: 3.07gears and 38\'s?

    Well, I'm going to disaggree and say that there is a point where really high gears are going to need so much input torque to get moving that the stress is much greater, and over the long run, could cause some problems. I imagine the pinion bearings hate those high gears.
     
  8. 70~K5

    70~K5 1/2 ton status

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    Re: 3.07gears and 38\'s?

    Nahh over the road big rigs run 3.08 and have 44" tires. But they have a 15.0 to 1 granny gear to get it rolling. In my pete I'm running 4.11s but I do alot of big hills and take it off road alot hauling construction materials. In long haul trucks they call it gear fast run slow. To keep the revs down at 75 mph and turn about 12 or 13 hundred r's As long as you have the overall gear reduction your fine. But 38" and 3.08s with a sb350/ T350 will be a real dog. I guess if you had a np203 and still fulltime you could use low range aroud town for more pep. Just rember to go to high range at higher speeds. Not reconmending this combo but it's not my truck either.
     
  9. Re: 3.07gears and 38\'s?

    I am son getting new tires but I dont want to re-gear quite yet, so I want your opinion on these two sizes. I have 4.11's and I am going to get either 36's or 38's. What do you think? How will it be with 36's and then how will it be with 38's? Thanks
     
  10. morphed86k10

    morphed86k10 1/2 ton status

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    Re: 3.07gears and 38\'s?

    I'm facing the exact decision myself. I'm going with the 36's because it is my daily driver, and I like the gearing as it is with the 4.10's and 35's.
     
  11. uglychevyZZ4

    uglychevyZZ4 3/4 ton status

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    Re: 3.07gears and 38\'s?

    higher is stronger?....LMFAO!!!! BOGGING EQUALS JERKING EQUALS BREAKING....i have 3:08's & 35's and its weaker and its like having my grandma pash a semi uphill! you have NO TORQUE and you might rethink putting 38's on 1/2 ton running gear, its easier to break axles with tires over 36. if you have a sm465 like me, you can use granny low as 1st gear, but it sux butt and you have no torque, couldnt pull squat! if you have an automatic, youll be X-TRA sorrrrrry!
     
  12. uglychevyZZ4

    uglychevyZZ4 3/4 ton status

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    Re: 3.07gears and 38\'s?

    confederate....you would want 4:56 whether you go 36 or 38. at least i would, i am going 4:56 with my 35's.so i can pull my tiny boat too. i lost all my freeway torque and my low range sux butt with my gears.
     

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