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.

Driveline angle and lifts

Discussion in 'The Garage' started by ike, Feb 4, 2006.

  1. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    Ive read the post regarding driveline angles. Some say keep the U joints at the same angle as eachother .. then some say shim the diff up and drop the transfercase down so the U joints point at eachother...Someone has to know this one... Im new to this fwd stuff...Im installing a 4'' bds lift and the angle of the drivelines look excessive I want to set it up right ...

    When talking about lifts what is ment by " zero-rate "

    If I drop the transfercase isnt that going to make a sharper angle on the front U joints???


    Thanks
     
  2. mouse

    mouse 1/2 ton status

    Joined:
    Nov 10, 2003
    Posts:
    1,448
    Likes Received:
    0
    Location:
    Great Falls Mt
    Good article on pirate: http://www.pirate4x4.com/tech/billavista/PR-shaft/index.html[FONT=Arial, Helvetica, sans-serif][​IMG][/FONT][FONT=Arial, Helvetica, sans-serif]Note that in the standard single-cardan shaft "match the angles" geometry the angles do not have to be the same "sign". THIS IS A COMMON MISCONCEPTION. Certainly, the most common method of achieving proper single-cardan shaft geometry is to set the transfer case output and pinion shaft centerlines parallel, thus achieving equal angles between each end of the driveshaft (pic at left). [/FONT]

    [FONT=Arial, Helvetica, sans-serif]Normally, this is done by rotating the axle housing (with shims in a leaf-spring suspension, or with relative lengths of upper and lower control arms with a link suspension). This is because the transfer case output is usually considered pretty fixed - the only way to adjust it is to either lower the transfer case (an all around bad idea and bad deal - I speak from experience) or to tilt the engine up (raise the engine mounts) again - not a good idea).[/FONT]

    [FONT=Arial, Helvetica, sans-serif][​IMG][/FONT][FONT=Arial, Helvetica, sans-serif]However - this is not the only acceptable method of achieving the proper matched-angle geometry. The angle between the driveshaft and pinion can be opposite to the angle between the transfer case and driveshaft - as long as they are equal. Note that they must still be in phase. This unusual configuration is called "Broken back" or "W" geometry (see pic at left ), and is common on agricultural equipment, marine drives, some tractor-trailers that use stub-shafts between front and rear of a tandem assembly, and most often on power-takeoffs like hydraulic pumps and PTO shafts. [/FONT]
     
  3. toy4x4runner

    toy4x4runner 1/2 ton status

    Joined:
    Nov 3, 2004
    Posts:
    122
    Likes Received:
    0
    Location:
    Tampa, FL
    don't run your U joints at more than 10 degrees. things will start getting weird after that. you might wanna look into doing a CV rear drivesahft. one of the best things I've ever done.
     
  4. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    zero rate

    What is a zero rate?
    Why cant I see the pictures you posted ?
    How do I measure the angles?
    So its a bad idea to drop the transfercase at all?
    thanks for any tips
     
  5. JpEater

    JpEater 1/2 ton status

    Joined:
    Nov 20, 2005
    Posts:
    299
    Likes Received:
    0
    Location:
    Augusta, Georgia
    A Zero Rate is basically a one inch block that also allows you to change your centering pin to axle location ( you can move your axle one inch forward or backward). It is sold by ORD and is a great product!. To check your driveshaft angle you simply use a magnetic angle guage that you may be able to find at a good hardware store but I do know that Welding supply shops sell them. Dropping your transfer case is good in some cases but bad in others. If your only running a 4 inch then more than likely a t-case drop nor a CV shaft is needed. All you need is the right degree shims and you should be good to go. What kind of rig do you have?
     
  6. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    Zero rate

    I have a 76 GMC Jimmy 350 / 350 Dana 44 front with a GM rear.203 transfercase that be converted to part time.
    I installed ORD steering box brace. Im installing a 4'' BDS lift with 33's
    I had longer front brake lines made and am sure ill have to do the same in the rear.
    With a zero rate why whould you install this ? More your diff forward or back?Will I need or shouls I get longer drive lines ? How do you adjust the front driveline ? ...Im in California ''' Thanks for the help...Im going to get a gauge asap... what angle should I go for ... ?
     
  7. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    Sorry my spelling and grammer is so poor ... Its a little hard for me to understand myself whaen I re read it ,,, I spent some time and made a real nice post for you but I wasnt logged in and when I tried to post it .. It was lost ... LOL so this is what we get ...
     
  8. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    Its = also my typing
     
  9. ike

    ike Registered Member

    Joined:
    Jul 5, 2005
    Posts:
    96
    Likes Received:
    0
    Location:
    orange ca
    Its = also my typing
     

Share This Page