Lowering a Peterbilt 379!!

Discussion in 'Trucks [ Eighteen Wheelers ]' started by EvilTrucker, Dec 16, 2008.

  1. EvilTrucker

    EvilTrucker Bobtail Member

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    Hey guys! i have a 1994 pete 379, is it possible to lower
    the front end about 2 to 3 inches? i was looking at it
    today and noticed a block under the front leaf spring,
    i was thinking about removing the blocks, it should
    lower the front end about 3 inches! anyone ever done this??
     
  2. Markvfl

    Markvfl Road Train Member

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    I think the cool guys run car hauler front axles which lower the truck a couple inches.
     
  3. Captain Canuck

    Captain Canuck <strong>"Captain of the Ship"</strong>

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    I don't think completely removing the block is advisable. It could mess up your front suspension geometry. Most lowering jobs I have seen were done by either using a car hauler front axle or using airbags.
     
  4. EvilTrucker

    EvilTrucker Bobtail Member

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    I agree!! the blocks that are on there are currently 4 inches tall,
    i could replace them with a block that maybe is only 1 to 2 inches tall?
    i would also have to buy shorter u bolts....
     
  5. ROBSREDFORD

    ROBSREDFORD Light Load Member

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    I did this on mine, the blocks are in mm on Petes, stock was 90mm or 80mm, I installed 30 mm block from another truck, so 50mm drop 2 inches worked fine. Most pete dealers will want a vin, I just walked around outside looking at trucks till I found one with the shorter blocks, that got my parts man in the right bin and we ended up with 30's , I think 20's are available. By using the factory blocks it kept the taper correct or at least close, i had actually considered just cutting my stockers, but the new ones were not alot of money. I had shorter ubolts made as I ran out of thread on my stockers, hope this helps. rw
     
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  6. heyns57

    heyns57 Road Train Member

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    I think those are called "caster blocks". Tapered shims may be added to get the proper caster. With proper caster, the truck will be equally responsive loaded or empty. When the caster is wrong and the load is heavy, it will take a bigger steering correction to keep the rig in your lane. Does caster make the steering return to center after turning?
     
  7. Markvfl

    Markvfl Road Train Member

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    Should be easy to do here in Orlando with a yard full of car haulers at the Pete dealer, right next to the auction. How does it handle?
     
  8. rjones56

    rjones56 Heavy Load Member

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    Check with Peterbilt or a trusted truck rebuilder/customizer first and save yourself a headache.Looking forward to the day I can start another project.
     
  9. EvilTrucker

    EvilTrucker Bobtail Member

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    wow!! thanks for the info!! you wouldn't happen to know the part
    number for those 30mm blocks would you? also would this effect
    the angle of my rear drive line?
     
    Last edited: Dec 16, 2008
  10. rockrawlin

    rockrawlin Bobtail Member

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    Yes it does.

    Not enough caster and the truck will wonder all over the road and the steering wheel won't return back to center as easily.

    Too much caster and the truck will drive straight but be hard to turn. It might also try turning on ya when you're backing up depending on how much caster you're running.
     
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