Jump to content

Rear Shackle interchange question


Recommended Posts

Hi, I am debating on a budget lift for my truck. What rear shackles are direct bolt ins that I can locate in a bone yard that would get me an inch or two? 1987 LWB. I can make spacers for the front.

I searched the site and could not find anything with specifications that were not related a specific lift kit manufacturer.

Link to comment
Share on other sites

I used XJ main leafs with the eyes cut off to gain two inches. You can use full size chevy drop shackles to gain lift too. Do a search...I don't remember the exact year and model truck that these shackles are found.

Link to comment
Share on other sites

If you want to go shackles, you can get a set of Chevy drop shackles on eBay for $40-50 new, and they usually have two mounting postions. One will give you about 2" of lift, the other about 1". If you buy aftermarket shackles that are for Jeeps, remember that XJ rear shackles are shorter than MJ's, therefore the advertised lift will be about 1/2 that on an MJ.

Link to comment
Share on other sites

Its been awhile since I offered the skinny on shackles, so here goes again...

 

First the facts:

 

The FACTORY MJ shackle measurement is 5-5.5" eye to eye.

MY leafs are longer, mounted spring under and have much more arch than a XJ's.

 

The FACTORY XJ shackle is 3.5" eye to eye.

XJ's leaves are much flatter, mounted spring over and shorter than a MJ.

 

As stated, advertised XJ shackle lift numbers will NOT jive with the MJ. Because as stated, the XJ shackle starts out shorter. Same story for XJ add-a-leafs. They do provide lift, but not as much as advertised for the XJ.

 

Shackles only lift one end of the spring, SO you need two inches of shackle length (over stock) to gain 1" of lift. Exp. 5.5" + 2" = 7.5" eye to eye measurement. Installing this shackle in a MJ will net you approx 1" of lift.

 

Installing longer shackles allow a lot of leverage to be applied to the leafs. SO, keep the shackles as close to factory as possible. A 5.5" on a XJ and 7.5" on a MJ is about as long as I would go.

 

Another big issue with shackle installs. Leave them LOOSE and drop the weight and jounce the vehicle. THEN tighten to final torque.

 

We are not talking front shackles here... BUT longer front shackles are a NO-NO as they ruin castor and kill approach angles.

 

CW

Link to comment
Share on other sites

Another big issue with shackle installs. Leave them LOOSE and drop the weight and jounce the vehicle. THEN tighten to final torque.

 

Just to add my 2c in here,

I also loosen the front spring eye bolts when I do a shackle install.

 

Then, like you said, cycle the suspension/bounce it a few times, before tightening all 6 bolts back up.

 

Probably doesn't make that much of a difference, but doesn't take that much to do it either (and it's a good excuse to lube those bolts).

Link to comment
Share on other sites

Probably doesn't make that much of a difference, but doesn't take that much to do it either (and it's a good excuse to lube those bolts).

It makes a HUGE difference. This is what happens due to tightening bolts with the Jeep still in the air (bushings go bad in about 6 months)

 

1002235largecw5.jpg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...