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.

2.5" Rancho lift (wedge and vibration)

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Redline, Oct 22, 2001.

  1. Redline

    Redline Registered Member

    Joined:
    Sep 30, 2001
    Posts:
    6
    Likes Received:
    0
    Location:
    NJ
    2.5\" Rancho lift (wedge and vibration)

    Hey guys,

    Just installed 2.5" lift on my 86 blazer. Came with 2.5" front springs and 2.5" rear block (shaved 2.5 deg.) and 6 shocks. Took about 2 days and 10 hours to install. Here are the questions:

    1) Once I installed the front springs, stupid me did not see the 2.5degree wedge that is supposed to sit under the front sping pack for "improved driveline" performance. Now... my stearing wheel sits about 30 degress too much (clockwise). Could this be the reason? Anyone have a similar experience?
    Do I need to install this wedge?

    2) I now have low speed vibration (5mph and 15-25mph). Gets worse when under-load. Is it time for U-joint replacement? How do I know if my driveline angle is acceptable? Did I do something else wrong!

    Appreciate any help you can give.

    By the way, rides great. No pull or sway and stops strait. Much softer ride than stock front spings/shocks. Would highly recommend the kit.
     
  2. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Re: 2.5\" Rancho lift (wedge and vibration)

    1 Your steering is crooked because you have increased the angle of the drag link. You need to adjust that. That is the short adjustable link between the steering arm on the axle and the pitman arm. That shim is needed to correct the pinion angle. It my not be a problem if your not full time.
    You may want to get a raised steering arm. With my springs I could get more droop that the tierod ends had avalaible movement. Idealy the drag link should be pretty close to level. Thos springs are closer to 4 inches of lift as measured to a stock truck. Even with the blocks I think you will notice the truck sits tail low. My has a 4 inch flip in the back and a extra over load and I just sit level as measured at the rockers. These truck even dead level look tail low. the truck tapers down from the dors back and the body line also drops as it goes back. measuring at the rockers is where the check for level.
    However I see a problem that you MUST check. I have rancho's that came with the shim and the centering pins were long so that they could pass through the shim and get good engagment with the holes. Without the shim the pins on my spring would bottom before the spring made contact with the pad. If this is happening the steering will feel sloppy and the u-bolt may loosen or even break. The springs could fracture across the section where the hole is also. VERY IMPORTANT THAT YOU CHECK!!!!!!

    2 What direction did you install the blocks? I ran those blocks on our 79 for a while. Didn't have any vibration problem. I cannot remember isif I put the fat side foward or back.

    Women dig dents and flat paint!
    <a target="_blank" href=http://communities.msn.com/OffroadK5s>communities.msn.com/OffroadK5s</a>
    75 Jimmy, Dollar
    Grim-Reaper
     
  3. Redline

    Redline Registered Member

    Joined:
    Sep 30, 2001
    Posts:
    6
    Likes Received:
    0
    Location:
    NJ
    Re: 2.5\" Rancho lift (wedge and vibration)

    Thanks for the suggestions....

    Rear blocks are fat side to the back.

    You are correct, those 2.5" springs are more than that. Tail does look lower and I have new stock springs in the rear with the 2.5" blocks. But man, does she sit nicer now!!!

    The vibration seems worse now after my first 30mile trek.
     
  4. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Re: 2.5\" Rancho lift (wedge and vibration)

    Ok the wedge to the back tilted the pinion up. You truck with the slip shaft is more prone to vibration. You can try putting it the other way but probably will need to drop the T-Case.
    It's stupid that you can't get a flat block. Really don't need a wedge at that low of lift if it had no wedge it probably wouldn't vibrate.
    You could try flipping the wedge forward.It might work but prbably be too little angle but worth a try. I persoanaly would not want to drop the t-case and loose any of the clearence if not totaly needed.

    Women dig dents and flat paint!
    <a target="_blank" href=http://communities.msn.com/OffroadK5s>communities.msn.com/OffroadK5s</a>
    75 Jimmy, Dollar
    Grim-Reaper
     
  5. Redline

    Redline Registered Member

    Joined:
    Sep 30, 2001
    Posts:
    6
    Likes Received:
    0
    Location:
    NJ
    Re: 2.5\" Rancho lift (wedge and vibration)

    Thanks Grim..

    Just oute of curiosity, do I need a 4W aligngment after this lift? Right now I run 32" tires on 11.5" rims. But for winter I change to 33'S on 12.5" rims.
     
  6. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Re: 2.5\" Rancho lift (wedge and vibration)

    No alingment needed. you didn't mess with the tie rod so nothing else is adjustable. Just adjust the drag link till the wheel is center and your good to go.

    Women dig dents and flat paint!
    <a target="_blank" href=http://communities.msn.com/OffroadK5s>communities.msn.com/OffroadK5s</a>
    75 Jimmy, Dollar
    Grim-Reaper
     
  7. eastk5

    eastk5 Registered Member

    Joined:
    Jul 24, 2001
    Posts:
    50
    Likes Received:
    0
    Location:
    Norfolk Virginia
    Re: 2.5\" Rancho lift (wedge and vibration)

    I have a rancho 2.5 and i didn' t use the degree shims in the front. the only vibration i've encountered is at freeway speeds coming from the rear. nothing to bad though, but i'm still going to get a cv joint rear shaft soon.
     
  8. ColAdo82K5

    ColAdo82K5 1/2 ton status

    Joined:
    Feb 18, 2000
    Posts:
    789
    Likes Received:
    0
    Location:
    MO
    Re: 2.5\" Rancho lift (wedge and vibration)

    Hey,
    Does anyone have any steering corrections (like drop drags or raised arms) for a 2.5 inch lift ? I have that Rancho lift on and my rear is low. Would 4 inch rear springs make it sit level ? I believe I need some new shocks, what would you recommend for P/N 's or length ?? Has anyone needed ext brake line for this lift ? I've had my lift installed a long time but havn't got the rest of the truck ready for off road yet. Anybody dissconnect the sway and drive on road ?
    thanks
    Blake
     
  9. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Re: 2.5\" Rancho lift (wedge and vibration)

    I put a 4 inch raised steering arm. I am able to get enough flex that the drag link bids without the steering arm correction.
    As for the shock. Find a place you can get full flex. Measure it. alow an extra inch of up travel. I get full travel You will be shock limited on droop on the front if you don't do the shock relocation mod (see the tech section). I run a shackle flip in the rear and ramps 752 with the front limiting.

    Women dig dents and flat paint!
    <a target="_blank" href=http://communities.msn.com/OffroadK5s>communities.msn.com/OffroadK5s</a>
    75 Jimmy, Dollar
    Grim-Reaper
     
  10. ColAdo82K5

    ColAdo82K5 1/2 ton status

    Joined:
    Feb 18, 2000
    Posts:
    789
    Likes Received:
    0
    Location:
    MO
    Re: 2.5\" Rancho lift (wedge and vibration)

    Grim,
    I'm assuming that you need extended brake line, did you buy them for a 4inch lift or what ? does the raised steering arm make your drag link sit ass high ? isn't it supposed to be front high from the factory ? is your sway dissconnected for your ramp testing only or for daily driving ?
    Blake
    p.s. Grim, you are the man, I print out your posts about stuff to save for reference (like your recent q-jet choke explaination)
     
  11. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    Re: 2.5\" Rancho lift (wedge and vibration)

    I may when I get around to relocating the shocks. I just used the drop brackets that come with Rancho's and even at max flex they still have a little left. If you get the ORD quick disconnects then becarful on the passenger side. When the suspension cycles with stock lines and the sway is pined out of the way the line can catch the pin. I use a short thin bungy and hook it around the line to the clamp on the spring to keep it from hooking the pin.

    Women dig dents and flat paint!
    <a target="_blank" href=http://communities.msn.com/OffroadK5s>communities.msn.com/OffroadK5s</a>
    75 Jimmy, Dollar
    Grim-Reaper
     
  12. Redline

    Redline Registered Member

    Joined:
    Sep 30, 2001
    Posts:
    6
    Likes Received:
    0
    Location:
    NJ
    Re: 2.5\" Rancho lift (wedge and vibration)

    Update...

    Dropped the transfer case about an inch and all vibration is gone.
     

Share This Page