1. Welcome to PlowSite. Notice a fresh look and new features? It’s now easier to share photos and videos, find popular topics fast, and enjoy expanded user profiles. If you have any questions, click HELP at the top or bottom of any page, or send an email to help@plowsite.com. We welcome your feedback.

    Dismiss Notice

1979 Blazer Rear End

Discussion in 'Chevy Trucks' started by jbholley, Sep 6, 2003.

  1. jbholley

    jbholley Junior Member
    Messages: 7

    Need Help Changing Gears in Rear End
    I just bought a 1979 Chevy K5 Blazer Cheyenne in GREAT condition, however it has highway gears under it. I'm wanting to change the gears out but don't want to completely ruin my gas mileage what little I get. I am currently running 2:76 gears I believe is what they are in a standard GM 12 bolt rear end. Any suggestions?:gunsfiring: :yow!: :help:
  2. reallyrusty

    reallyrusty Member
    Messages: 71

    Are you sure they are 2.76s. That sounds awfull steep for a 79 vintage.
  3. wyldman

    wyldman Member
    Messages: 3,265

    They are most likely 3.08's.They didn't even have 2.73's until the mid eighties.

    You can swap the gears,but you'll need to swap front and rear as well,so your 4WD will still work.Ring and pinion sets are not too expensive,but you really need to know what your doing to change them.If you don't feel confident changing a gearset,then take it to a shop who can.
  4. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    agree with all thats been said thus far....setting up gears is definatly a job for a novice....

    If you want to dump the gears I would look into getting 3/4 ton running gear and swaping the rear and front axel. More beef and better gearing and if you hunt you might score one with a locker. And now would be the time for a mild lift if you are thining of one.

    a shop should be able to swap running gear in a day or close to it.
    50$an hour x 8 hours=400$ and if you score the gear from them and let em keep yours they might not ding you much for the parts

    your probably going to drop 300$ in parts for the gear swap plus set up if you have someone do it for you.

    depending on what deals you can work out it might not be much of a price difference. Better do your home work when you go looking for a shop though. or do the running gear swap yourself?

    What size tire do you have? What tires do you want to run if you lift it? That detirmins what gears you should get
  5. jbholley

    jbholley Junior Member
    Messages: 7

    hey i just want to say thanx to everyone here youve been a big help.According to my Service Parts Identification on my Blazer it says Option # 1HC2 Rear Axle 2.76 Ratio. Im wantung to go from 31 x 10.50 to 33 x 12.50 without cutting on the body. Any more information would be great and don't worry your not the first ones to say theres no way that Blazer has 2.76 gears in the rear end lol.:drinkup: :drinkup: