Optimal Shackle Angle - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Optimal Shackle Angle

Rough Country Lift Kits and Parts!The ULTIMATE "Selectable" Locker System! BroughIntroducing MONSTALINER™ UV Permanent DIY Roll On Bed Line

Reply
Unread 01-13-2014, 08:36 AM   #1
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Optimal Shackle Angle

Hey guys,

So I went out wheeling yesterday and ripped the front hanger from the frame on the passenger side. I'm getting new RuffStuff hangers and will be putting her back together this weekend.

So here is my question. I am currently on procrap springs that flex pretty well but still ride very stiff. I am toying with the idea of moving the perches toward the rear of the frame, changing my shackle angle. Currently with 2.5 in lift springs and stock hangers/shackles my shackles are nearly perpendicular to the frame (90 Degrees). I know too severe of an angle can cause the axle to walk, so My thought was a 75-80 Degree angle in front would be an improvement over my current setup. I will also be adding some 5/8in lift shackles from BESRK here on the forum. My plan is to install the boom on the good side and let the jeep rest on its own weight. From there i can see if the booms change my shackle angles or not (i have also done calcs but would like to double check). My heep is my DD so i would like to improve ride quality on and off road if possible. Thoughts?

jsipe007 is offline   Reply With Quote
Unread 01-13-2014, 10:42 AM   #2
Anticanman
Follow me
1994 YJ Wrangler 
 
Join Date: Aug 2009
Location: Ripon, California
Posts: 19,223
Length of the new shackle will change the angle of the shackle drastically under cycling of suspension. My suggestion: replace the mounts in their stock location so that one day you won't be shooting yourself in the foot if you decide to replace your springs.
__________________
Luck Favours The Prepared
[SIGPIC][/SIGPIC]
Anticanman is offline   Reply With Quote
Unread 01-13-2014, 11:01 AM   #3
Mobile_Homie
Desert Rat
 
Mobile_Homie's Avatar
1994 YJ Wrangler 
 
Join Date: Jun 2008
Location: Winnemucca, NV
Posts: 1,229
Get the shackles in hand before you weld those on. Eddie can/will have those out pretty quick.
__________________
Mark



Smoke em if you got em!

Click here
Mobile_Homie is offline   Reply With Quote
Unread 01-13-2014, 12:51 PM   #4
Norcal_chris
Senior Member
 
Norcal_chris's Avatar
1995 YJ Wrangler 
 
Join Date: Jan 2012
Location: Sacramento, CA
Posts: 638
I moved my shackle mounts back with 4.5sua springs and it made a tremendous difference in ride as well as droop.

If you took your stock hangar, sliced it off the frame, and turned it 180deg that Is were mine ended up.
__________________
2.5/doubler,D60/14bff,104WB,H1s,39.5IROKS
Norcal_chris is offline   Reply With Quote
Unread 01-13-2014, 01:48 PM   #5
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Thanks guys! Sorry if I wasnt clear before, I have the shackles in hand. My thought was to install one on the stock hanger, check the angles and then decide if i should install the beefy ones in the stock location or not. I dont see myself installing new springs for many years but it is something to keep in mind
jsipe007 is offline   Reply With Quote
Unread 01-13-2014, 04:22 PM   #6
Sparrows
It's coming...
 
Sparrows's Avatar
1995 YJ Wrangler 
 
Join Date: Dec 2012
Location: Boise, ID
Posts: 4,526
Quote:
Originally Posted by Anticanman View Post
Length of the new shackle will change the angle of the shackle drastically under cycling of suspension. My suggestion: replace the mounts in their stock location so that one day you won't be shooting yourself in the foot if you decide to replace your springs.
Quote:
Originally Posted by Norcal_chris View Post
I moved my shackle mounts back with 4.5sua springs and it made a tremendous difference in ride as well as droop.

If you took your stock hangar, sliced it off the frame, and turned it 180deg that Is were mine ended up.
Usually I don't disagree with Nick, but I have to side with Norcal_Chris on this one. After exhaustive and extensive research, and a bunch of VERY long conversations with some very well respected people in the industry, I've learned that having a "flatter" shackle is much more desirable than one that rests nearly perpendicular (90*) from the frame. I myself plan on 35-45* shackle angles and going from there.

There are dozens of very long and very informative threads on Pirate4x4 on the subject of shackle angle, with all the math, diagrams, and numbers you could ever handle.

Good luck.

Cheers
__________________
WARBIRD 2
EXILED OFFROAD
June '13 YJOTM
Sparrows is offline   Reply With Quote
Unread 01-13-2014, 05:44 PM   #7
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Thanks Sparrows! After doing more research, I am fairly certain I will shift the mounts to give me about a 20 degree angle with only the weight of the jeep on the suspension. I may have to re-do them in future but I will cross that when i come to it
jsipe007 is offline   Reply With Quote
Unread 01-14-2014, 08:30 AM   #8
bgredjeep
Registered User
1987 YJ Wrangler 
 
Join Date: May 2005
Location: Augusta, GA
Posts: 1,588
Its only metal. You can always cut it off and stick it back together if you need to.

If you are already cutting and welding stuff, you might consider replacing the shackle hangers in the stock location and move the frame side spring hanger forward an inch or so. Get the better shackle angle and a little extra wheelbase.
bgredjeep is offline   Reply With Quote
Unread 02-05-2014, 05:39 PM   #9
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Just an update, last weekend I welded the new hangers onto the frame. I went with ruffstuff shackle hangers and am extremely pleased with how they turned out. The new hangers shifted my shackle mount toward the seats, giving me approximately an 70-75 degree angle instead of the 90 degree angle I had. She rides great! Really loving the change. I also installed 5/8 lift shackles from ground pounder fab, new bushings and hardware on all four corners. I still have to shim the fron axle a couple degrees, I now do have a bit of bumpsteer that needs correcting. I took angle measurements before and after though and that should be an easy fix. New shackle plates, u bolts, and homemade u bolt skids going on next!
jsipe007 is offline   Reply With Quote
Unread 02-06-2014, 12:57 PM   #10
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
So I got a question for all you on JF. Can a poor caster angle cause bump steer? I'm running no trac or sway bars, 3 in lift and since installing the 5/8 lift shackles I have been experiencing a bit of bump steer. I took measurements and plan to install 2 degree shims with the new u bolts and hardware, hopefully returning my pinion angle to how it was before. Do you guys think this will fix my slight bump steer? My impression is that it will help, realigning the drag link to move only vertically and not as much horizontally,reducing bump steer.
jsipe007 is offline   Reply With Quote
Unread 02-06-2014, 02:19 PM   #11
bgredjeep
Registered User
1987 YJ Wrangler 
 
Join Date: May 2005
Location: Augusta, GA
Posts: 1,588
Not related. Bump steer is caused when the drag link is at an angle from the pitman arm to the tie-rod (or knuckle). When your suspension compresses (think speedbump) the distance between the pitman arm and tie-rod attempts to get shorter. This means either the steering wheel turns, or the wheels turn to account for that change.

Caster can affect your tracking and return to center while driving, and it my reduce the effect on the wheels that bumpsteer is able to have, but you'll have that much more of the bumpsteer transferred back to the steering wheel if that happens.
bgredjeep is offline   Reply With Quote
Unread 02-06-2014, 02:32 PM   #12
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Thanks for the info! I may be mistaking another problem for bump steer. I'll look into it and post back.
jsipe007 is offline   Reply With Quote
Unread 02-06-2014, 02:55 PM   #13
Anticanman
Follow me
1994 YJ Wrangler 
 
Join Date: Aug 2009
Location: Ripon, California
Posts: 19,223
Pull the shims if the angle isn't right. There is a margin for error but all little things can exacerbate the scary experience.
__________________
Luck Favours The Prepared
[SIGPIC][/SIGPIC]
Anticanman is offline   Reply With Quote
Unread 02-06-2014, 03:10 PM   #14
jsipe007
Registered User
1994 YJ Wrangler 
 
Join Date: Oct 2011
Location: Reno, Nevada
Posts: 446
Thanks Anti. I have not installed the shims yet but took careful notes and did calcs when installing the shackle lift. I'm just waiting on the steel shims to arrive then I'll post back
jsipe007 is offline   Reply With Quote
Unread 02-06-2014, 03:16 PM   #15
CrawlingForward
Rookies Happen.
 
CrawlingForward's Avatar
1995 YJ Wrangler 
 
Join Date: Nov 2008
Location: Brazoria, Texas
Posts: 2,298
I'd love to see pictures and learn a bit from the process if you get a chance!
__________________
My Other Jeep Is A Jeep - Crawlingforward's Jeep-Related Adventures

95 YJ, Rio Grande - The Wannabe Sleeper Wheeler
2010 JKU, Islander Edition - The Burly Stock Overlander

- North Shore Jeep Club -
Build/Wheel/Break/Educate/Upgrade/Repeat
CrawlingForward is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.