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1972 Dana 44 axel numbers what do they mean?

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by BozoWise, May 15, 2002.

  1. BozoWise

    BozoWise 1/2 ton status

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    I just removed the cover and here is the scope stamped on the ring gear. I would guess it was made in 12-9-72 but what do all the numers mean?

    12 9 72 DANA 18520 A3035 45-11
     
  2. chulisohombre

    chulisohombre 1/2 ton status

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    im not sure about the numbers.are you trying to find axle ratio?if its trhe stock gears more than likely it is a 3.73 to 1 ratio.check your glove box door and it will say there also.
     
  3. BozoWise

    BozoWise 1/2 ton status

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    45 is ring gear and 11 is pinion for a 4.09 gear ratio.

    Can you run fulltime with a 4.09 in the front and a 4.10 in the rear?
     
  4. 70~K5

    70~K5 1/2 ton status

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    The '77 K20 I had was a 400sb t350/ 203tc and came stock with 4.09f/ 4.10r gears.
     
  5. Triaged

    Triaged 1/2 ton status

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    You can run full time with 1% difference. 4.09 vs 4.10 is a .2% difference...well withen the acceptable range.
     
  6. Burt4x4

    Burt4x4 3/4 ton status

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    Yup, I run 4.11 Rear and 4.09 front.
     
  7. POFF

    POFF 1/2 ton status

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    I have 4.09 front and 4.10 rear. I talked to my drivetrain guy about it. He said they do that so the front axle pulls the rear slightly. It makes the truck handle better. You are correct on the ratio.
     
  8. Blazer1970

    Blazer1970 1/2 ton status

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    They do it just because that is as close as you can get with certain models of axles. The number of teeth on the ring gear, and the diameter of the ring gear dictates the exact ratio that can be achieved with a given axle design. Normal differences in tire wear from front to rear will make a lot more difference than 4.09/4.10/4.11 :1.
     
  9. chulisohombre

    chulisohombre 1/2 ton status

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    you can run 1% difference.which means 4.08 all the way to 4.12 would still be with in tolerance.
     

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