Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

GEAR QUESTION

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by TB2Blazer, May 12, 2003.

  1. TB2Blazer

    TB2Blazer 1/2 ton status

    Joined:
    Apr 6, 2002
    Posts:
    166
    Likes Received:
    0
    Location:
    Cleveland, GA.
    How can I find out what gear ratio I am running in my 85 K5. I've got a 14ff that I am going to put in the rear of my blazer that came from an 85 sub but I don't know the gear ratio in either of them.
     
  2. 89GMCSuburban

    89GMCSuburban 1/2 ton status

    Joined:
    Nov 15, 2001
    Posts:
    3,005
    Likes Received:
    0
    Location:
    Thornton, CO
    Yank the cover and count the teeth on the ring and pinion. The other way is to jack up the rear end, mark the pinion yoke and tire, turn the tire 1 full turn and count how many times the yoke turns.
     
  3. Shaggy

    Shaggy 3/4 ton status

    Joined:
    Dec 15, 2000
    Posts:
    6,737
    Likes Received:
    0
    Location:
    Los Banos, CA
    <font color="green"> There was a tag inder one of the diff cover bolts when the truck left the factory, that's the easiest way if they're still there. The tooth counts are also stamped on the edge of the ring gear. The stamp is generally the most accurate way to find out the ratio.</font>
     
  4. dyeager535

    dyeager535 1 ton status Premium Member

    Joined:
    Dec 13, 2000
    Posts:
    26,980
    Likes Received:
    189
    Location:
    Roy WA
    I think they stopped using the tags in the 70's. Have never seen mention of them in the 80's service manuals. Only tag I've seen are the "limited slip diff" tags.

    Gear ratio code is stamped into the passenger side axle tube, no reason for GM to put a tag on it as well.
     
  5. K5MONSTERCHEV

    K5MONSTERCHEV 1/2 ton status

    Joined:
    Jan 27, 2003
    Posts:
    3,254
    Likes Received:
    0
    Location:
    Castro Valley, CA
    yeah, drive for 1 revolution of the tires, see howmany thimes the driveshaft truns.
     

Share This Page