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blocks in the front

Discussion in 'The Garage' started by blazerpro79, Mar 7, 2005.

  1. blazerpro79

    blazerpro79 1/2 ton status

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    why is it dangerous to run blocks in the front? im not considering it because blocks are ghetto as hell, but just wondering.
     
  2. AkMudr

    AkMudr 1/2 ton status

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    Because they arent part of the leaf spring pack nore part of the axle. They can get squeeze out, I saw it happn about 4 months ago at a mudbog, and it wasnt a boggin truck..it was someones DD. Just generally unsafe.
     
  3. txfiremank5

    txfiremank5 1/2 ton status

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    I may be wrong, but I always though it had to do with the fact that so much of the trucks weight is up front.. and then having the "stack" effect of a block sandwiched between the axle & springs could cause failure. Like what AKMUDR said...

    I blelieve the reason they are "ok" in the rear is that there is less weight, and in addition, the vehicle is "pulling" the rear axle over obsticles (plus it's drive input) where as the front sort gets "pushed into" obsticles. It's sort of hard to explain.. :confused: :grin: Pushing the front axle into the obsticle places a great amount of laterial stress on the front suspension... and with blocks, the added leverage would/could work against the system and cause it to shear, break, or come apart.

    Something along those lines anyway... I know what I'm trying to say.. just not sure I'm making it understandable for everyone else. :blush: :crazy:
     
  4. 84_Chevy_K10

    84_Chevy_K10 Banned

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    The reason is because the front axle steers. The forces of steering can easily break, spit out, etc. a block and that is why it is unsafe.
     
  5. BIG*RED

    BIG*RED 1/2 ton status

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    this is kinda off topic, but remember back in the day before we has these fancy lift springs guys would lift their trucks with blocks?..well some still do, but i remember years and years ago seeing dozens of trucks with two 4 inch blocks stacked on top of each other to get their big lift...or maybe that ws just a california thing? lol
     
  6. jekbrown

    jekbrown I am CK5 Premium Member GMOTM Winner Author

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    yeah, we have learned over time. Blocks up front aren't a good idea. That said, a "block" that was properly welded to the spring perch (or just a whole new perch that was taller by design) shouldn't be a problem.

    j
     
  7. cbbr

    cbbr 1 ton status GMOTM Winner

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    What is different (besides size) when using a zero rate on the front? It may be just size reducing the force place upon it, but i'm just wondering because I am considering moving mine from the rear to the front and getting lift springs for the rear (rear is sagging).
     
  8. AkMudr

    AkMudr 1/2 ton status

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    Zero rates are bolted to the spring pack and are safe becuas eof that, and because of they are only 1". Lift blocks float between the spring and axle and arent secured by by anything except weight and the ubolts.
     
  9. az-k5

    az-k5 1/2 ton status

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    A lift perch is okay to a point. You still have a leverage issue on the u-bolts. They tend to snap under that type of loading.
     
  10. big jimmy 91

    big jimmy 91 1/2 ton status

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    Just a general observasion...

    Every big rig I have worked on has front blocks on the steering axle (3-4"?)
    I have never heard of them loosing a block unless it was in a severe accident
    Alot of these trucks go a million miles in their service life without a problem
    Now I just wonder how they get away without problems , is it because it's just a steering axle with no forces applied to it by 4X4 running gear
    There must be a lot of forces involved steering a loaded rig around?

    I agree that front blocks are not a good thing in a 4X4 and was just wondering about the rigs???
     
  11. jekbrown

    jekbrown I am CK5 Premium Member GMOTM Winner Author

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    true dat. Im talking about an inch... maybe two. There are definitely limits. Lots of guys running rockwells have pretty high perches tho...

    j
     
  12. 70~K5

    70~K5 1/2 ton status

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    I've made the same point everytime someone talks about braking torque on front axles and blocks. Most big rigs I've driven has had front blocks.
     
  13. 4trolls

    4trolls 1/2 ton status

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    I had a j4000 with 2.5" blocks in the front, welded to the perch, it seemed to where out ball joints fast but I dont know if that was why. The whole truck was micky mouse
     

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