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Spring Perches, Rear Shock Absobers & Cross Member

Discussion in '40- & 55-Series Tech' started by Guest, Mar 1, 2003.

  1. Guest

    Guest Guest

    Leaf Spring over Axle conversion on BJ40[I realise this has been covered before on numeous occasions, But I need straight, clear and direct answers]

    Shopping List:
    U Bolts
    Brake Lines
    Spring Perches
    [Who makes them and Where can I get them?]

    Can I use OME Nitrocharger Shock Absorber rears on the front?
    What do I do with the Cross Member[Put spacers in or remove completely]
    What should I do with rear Dampers[have none or get longer ones?]

    Anything I've forgotten?


    Thank You for your contribution :)
     
  2. Niner

    Niner

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    the list sounds complete! the dampers as you call them I believe to be bump stops. if they are I just spaced mine down, otherwise you will over extend the springs giving them the mustach ({)look.
     
  3. Slowerthanu

    Slowerthanu SILVER Star

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    Explain to me what you mean by rear crossmember spacers?

    Use mopar spring perches for 3 inch tubes http://store.summitracing.com/partdetail.asp?part=18932

    cheap and effective.

    I would use custom shocks all around, woody likes the Doetch tech's, I have heard good things about the Bilstein 5100's (Not too expensive). If in america use Napa U-bolts or have some bent locally (I actually cheated and used some Ranchos, Napa was out).

    Get newrear shocks, axle hop could be a problem.
     
  4. axlechassis

    axlechassis

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    you can also get the mopar spring perches straight from dodge for $12 a set.
    For brake lines move the front line and add it to the rear then find a used rear line to replace the front line.
    If you  turn the springs around you can gain about 8 inches of wheelbase greatly improving highway ride and handling with very little turning circle sacrifice and also improving driveline angles. (I have heard not turning the spring around results in a little bit of twitchy handling on the highway, Most of us have to drive down the highway to the trailhead)
    for shocks use  the longest Rancho 9000's, The valving of this shock is perfectly suited for this application, have new front shock towers made. in the back  move the lower shock mount in an inch  to assure shock spring clearance.
    I used stock front springs for both front and back with very pleasant results.
     
  5. Guest

    Guest Guest

    Re: Spring Perches, Rear Shock Absobers & Cross Me

    Today I replaced the front Leaf Spring Centre Pins. :)


    The only problem I have is the Transmission Cross Member needs to be lowered. The front Tail Shaft at full drop is resting on the Cross Member[Any ideas on what to do?]. ???


    Will the Mopar Spring perches work on the front right?

    Who makes U-Bolts that have a Backing plate and
    that are square(Not rounded) at the end(Like on a Toyota Hilux/Pick up)?


    Thanks for the Information thus far :D
     
  6. Guest

    Guest Guest

    Re: Spring Perches, Rear Shock Absobers & Cross Me

    [​IMG]
    [​IMG]

    Will I need High Steer Arms?
    Can I use the U-Bolt and plate off of a Toyota Hilux/Pick up?
    Is the front right Spring perch the same as the rest?

    I still need to work out what to do with the Transmission Cross Member.
     
  7. Slowerthanu

    Slowerthanu SILVER Star

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    Will I need High Steer Arms?
    Can I use the U-Bolt and plate off of a Toyota Hilux/Pick up?
    Is the front right Spring perch the same as the rest?

    I still need to work out what to do with the Transmission Cross Member.[/quote]

    Man-A-fre, Specter, Cool Cruisers and many others carry the square u-bolt.

    You will need Hi-steer arms or a double arm for proper steering.

    You need to grind out the right spring perch a bit for it to work, this is a trial and error thing.
     
  8. Guest

    Guest Guest

    Re: Spring Perches, Rear Shock Absobers & Cross Me

    With the front Tail Shaft on full drop resting on the Transmission Cross Member I will have to put some type of spacers in.

    But the only possible couse could be that my front Tail Shaft has a larger diameter! :-[

    So I take it that no one has ever had to do any thing to the Cross Member?


    If I can't work out how to do the Cross Member I will can the project.
    I will be buying a Hilux in a couple of years anyway. 8)
     
  9. theferg

    theferg

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    Jonathan,

    You may be mixing-up some of us Stateside cruiserheads when you call it a tail shaft. We call them drive shafts over here....anyway, there are plenty of people who have done an SOA and had issues with the shaft hitting the cross-member. The thing that is most commonly done is to notch out the cross member a bit so the shaft does not hit it at all. Hope that helps.
     
  10. Guest

    Guest Guest

    Re: Spring Perches, Rear Shock Absobers & Cross Me

    Actually in Australia we call them Propellor Shafts. :D
     
  11. Guest

    Guest Guest

    Re: Spring Perches, Rear Shock Absobers & Cross Me

    This is what I asked Darren McRae[Who did a SOA on a FJ40 and has modified many Landcruiser including a Prado and 78 Series and ahs also competed in many competetions]


    This is the response I got


    I decided not to go ahead with the SOA, If I were to do a lift I would go with an Australian company called 'Ultimate Suspension' who are renowned for their good products for use in the Thai and Malaysian Jungle and Rain Forest. Also If I were to do a lift it would be no more than 2.5"-3".
     
  12. axlechassis

    axlechassis

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    The mopar spring perch will work on the front right you have to grind it out and shape to fit.
    I was wondering why they used the square u bolts in the pictures? If you use the round ones it is much cleaner under the axle. One of the reasons for a spring over is to reduce the amount of stuff hanging under the axle that creates drag. Those underside square u bolt brackets look like big mud brakes.
     
  13. rick_d

    rick_d

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    you guys and your "full stop"...

    front driveline (prop shaft). Use a thin neck later FJ60 or FJ62 front shaft or double carden (double U joint) from hilux (or J60?)

    damper = shock, bump stop = bump stop (rubber)

    mopar "seats" are $9.90 a pair here in expensive Cody, WY. @ 61 cents a dollar not bad (too bad we are not at 54 cents anymore)

    and a track bar (decker's is clean....)
     
  14. Mavric1298

    Mavric1298

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    I agree about the ubolts, get the round ones, and put them around the axle, instead of using the u-bolt retaining plates. And i disagree with that comment that this is a worthless conversion and unsafe, if you do it right, its just as safe as a 4" lift
     
  15. woody

    woody Internet Fireman Staff Member

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    SOA vs SUA, 350 vs inline 6, Scout vs GM vs minitruck PS conversions....etc etc...

    All are opinion, and until you've experienced each in YOUR wheeling environment and for YOUR driving style, other opinions are useless.

    For the type of wheeling I do, my SOA, 38.5" tires, Scout PS, and 350 TBI are perfect.
     
  16. axlechassis

    axlechassis

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    Re: Spring Perches, Rear Shock Absobers & Cross Me

    And when the springs are flipped around there is a significant improvement in highway stability over the stock spring under set up.