(TOM) Shackle Flip

[derf]

Ok, so we can do a SOA in the front. How about flipping from a suspension shackle to a lift shackle in the rear?

How much lift should I expect? Do I have to custom fab or is there a kit? How does it affect ride and handling?

[ November 05, 2001: Message edited by: Sitting Bull ]

[River Beast]

This has got to be the most elaborate modification I have accomplish thus far. I know shackle flips are common on other rigs, but I have done more than the just the shackles. I have dropped the entire rear suspension 7" to compensate for the SOA up front because I don't like using lift blocks.
http://home.earthlink.net/~riverbeast/rear_files/image007.jpg

I had done alot of math, several different times with several different designs, before deciding on the best one. It took about a week of paperwork (drawings and math), a bunch of encouragement from friends and fellow FSJers and about 80 hours of labor involving cutting, fabricating, welding, measuring and lots of "head scratching" (hehe) to complete the rear suspension mods. All said and done... it works!!! I had three separate designs in all before finalizing the finished product. A lot of hard work, patience and determination DOES pay off!
http://home.earthlink.net/~riverbeast/rear_files/image010.jpg
The inversion bracket for the rear shackle was fabricated from ¼” thick 3.5” box steel cut and drilled to specs I had formulated during the “head scratching” days in the beginning. This is the final design… yes…it’s a bolt-on application. No welding is required on the part of the installer, just the manufacturer, (me!).
http://home.earthlink.net/~riverbeast/rear_files/image012.jpg
The front hanger of the rear spring was much more in detail than the rear to design. It needed to be strong and re-enforce the remaining portion of the factory mount. Again I used the ¼” thick 3.5” box steel to fab the mount. I re-enforced it with 2.5” angle iron. And again… this is the final design. As it’s sister mount, this too, is a bolt-on application after removing the about ¾” off the bottom of the factory mount with an angle grinder.
http://home.earthlink.net/~riverbeast/rear_files/image014.jpg
No lift blocks, see?

One of the reasons it took as long as it did for me to be satisfied was the fact that I want it safe and strong. One of the strong points of this modification is it’s not set up to be permanent. I haven’t tried this yet but, I figure within a 8-10 hour period, I could easily revert back to the factory mounting positions in the rear as well as the swapping the SOA up front. The other mods that have been done to my FSJ to accommodate the monster lift are also easy to revert… like the shock mounts. The factory brackets are still in tact and useable…front brackets get removed and plates just get re-bolted to the frame. Some day I will revert back to have EXTREME fun with a set of 33’s…4.89’s will be WILD with 33’s I’m sure!

I hope this helps...

[jeepbob]

Those of us with early (pre 71 for sure possible until 74, a little help here please)rigs have it much easier. All we have to do for a shackle flip is jack pu the frame, unbolt the spring from the shackle, jack up the frame a little more, flip the shackle over, and bolt the spring back to the shackle. Of course it is much tougher to do a susp lift like RB did. although now that I think about it, it could be done as a bolt or weld on fairly simply by making a drop bracket that went over the front mounting post and bolted or welded to the bottom of the rail for strength and then used lift shackles in the rear. I think this is what I will do to level out my rig when I finally finish the SOA. Thanks RB.

[River Beast]

One thing to remember when flipping a pre-74 post type rear shackle... when this is all you do, you will change the angle of suspension operation alot, thus moving your wheels forward by about 1-2". To correct this, you can grind off the factory rivets holding the post mount to the frame, make a new mounting plate that you can attach to the frame and drop this post mount dount to the location needed to level the springs back out after doing the flip...

I have seen just the flip done on the rear and after a good flex and droop it shot up to the orignal position.... relocating the post lower on the frotn would keep the flip in it's proper position.

[jeepbob]

RB,
The forward movement is about 1 inch, when I did the flip I also added a couple of extra leaves so I do not have the droop unflip problem even on a very hard landing after being airborne :eek: Jst gringing off the rivets will not allow the post to come out as it goes thru the frame rail and is welded to the rail. I moved these once and it was a BIG pain in the rear and I would never do it again. I would cut them off and put a different style on first.

[River Beast]

Jeepbob,

...understood..... I do realize how much of a P.I.T.A certain things can be to modify....I got the t-shirt once or twice... ;)

[la mula pescadora]

i started doing my shackle flip about a month ago and i still havent finished it really is a little complicated a lot of mesuring and math involve i will defently recomend the shaclke flip but bolt it don't welded or just tack it and make sure u have all level out if not ur are going to have fun trying to unweld everything

[shadowjeep]

hey RB, whats the odds on you fabbing up some of mounts? id like to do the flip for the future installation of revolver shackles. im not a fabricator. are there an easier route on this? dumb question, i know.

[oldyellowwagoneer]

If RB doesnt have time to make you some just go to a wrecking yard and get 4 front spring hangars from a 80's dodge 4x4.Weld them under the spring buckets just like RB has his.Make sure to mount the shackle mount forward about 1 1/4 to 1 1/2" depending on shackle length.This is probably the cheapest way to go.Thats how I did it!!
SCOUTGRL

[derf]

Hey River Beast,

Is there any way you can write up the designs for those parts you built and put them in a picture file of some kind? If it is truly bolt on, I may want to fab some of them and bolt them on mine. smile.gif

I found a line on a rear Dana 70 to replace my AMC 20 so I can put some real tires on when I lift. :D

Oh, and what size tire should fit with the SOA/Shackle flip lift?

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Rick:
hey RB, whats the odds on you fabbing up some of mounts? id like to do the flip for the future installation of revolver shackles. im not a fabricator. are there an easier route on this? dumb question, i know.<HR></BLOCKQUOTE>

I am planning on making kits... I have a list of members here that are patiently waiting..thanks guys for your patience.

The only tools needed for the install are common handtools and an angle grinder to remove some uneeded metal on the front and rear.... most of the grinding is on the front mount. IT's quite easy.... I have to finalize the "destructions" ;) and get a chop saw...I have aquired the rest of the tools already, drill press, bench grinder, welder and other little things that make life easy. Then I have to go into Los Angeles to get materails.... no metal shops around with the selection I need.

[newbie]

RB, you gave me these before, but I'm afraid I misplaced them...Could you give me the dimensions of your re-located hardware??? (eg. how far down is the new spring hangar from the orig. position, how far forward is the new shackle mount, and how far down did you make it?)

[derf]

<BLOCKQUOTE>quote:</font><HR>Originally posted by River Beast:
I am planning on making kits... I have a list of members here that are patiently waiting..thanks guys for your patience.<HR></BLOCKQUOTE>

Ooooh. Kits even. How much? When do you expect them to be ready?

[Lindel]

Todd, add me to the list of patient customers!! :D

Tell me how much, when the time comes, and we'll go from there.

BTW, did I mention you do good work? ;)

[blt2krl]

I have a dumb question. why can't you just cut off the bottom plate on the shackle mount , flip the shackle and weld a new plate to the top of the shackle mount? Sheed some lite on this for me. You guys talk about math calculations. What are you calculting. One more question I have is, can you do a shackle flip on a vehicle that doesn't have a spring over in the front. I want the rusty 6 in and would like to not run blocks in the rear. Would I get 2in with a shackle flip or miore like 4 to 6 in? I apoligize for my lack of knowledge on this subject.

[River Beast]

Lindel.... I will let you know.... :D

As for the kits.... they will be reasonably priced I have to figure in my time and laber plus the cost of material AFTER I find a new supplier....


blt2crl,

Not a stupid Q at all.... I'll try top explain it.

The main reason for a shackle flip (in my eyes) was to compensate the 7" I gained from the SOA.. I HATE BLOCKS!!! :mad:

Just "flipping" the shackle as you described will not give you the amount of lift needed to "level" the FSJ back out. You can do this, but still need to fab a front mount so the spring will work properly and not at an angle of up and back.... up and down is how they are designed to work.

You can "flip" the shackle like you said... but remember to to fab a front mount to drop the front of the spring low enuf to level the the suspension... and this may not be enuf to sompensate for a SOA.


A little food for thought here:

If you were flip the shackle by cutting the bottom out...the total distance the spring moved is about 6" in the rear.... giving you a total of about 3" of lift AT THE CENTER OF THE SPRING (geometry works well on paper for a visual on this using inches here with ANY length of line)...not...BUT now you must "level the spring somewhat by fabbing a front mount of about 6" down to give the 3" in front needed to level the spring... thus giving you only 3" of total lift.... you would still need a 3" block to get your 6"

Why not just order a 4 spring 6" suspension system and SCREW BLOCKS!!!! you will be much happier... TRUST ME....

[ October 23, 2001: Message edited by: River Beast ]

[Iron Horse]

Hey RB,
I think what Blt2clr is asking is that he is looking for a way to compensate for the 2" blocks that the Rusy's 6" kit comes with. I have this kit also and I'll live with the blocks but....I'd like them to go away. We only need to get 2" at the rear axel (instead of the blocks) to match the 6" of lift at the front provided by the kit

If you *only* flipped the rear shackle and got 3" at the center, then the blocks could go, yes/no? But....what does this do to the pinion angle? Could you get enough correction wedges(?) to bring it back within spec.?

[ October 24, 2001: Message edited by: Iron Horse ]

[River Beast]

ahhhhh... "I see!!!", said the blind man.... :D I didn't know Rusty's 6" kit came with 2" blocks.

Now for this application... I believe what you both are trying to do will work...maybe... since you are not moving the shackle mounting point forward a good 1.25", it may want to pivot forward... this happened on my first attempt at this "flip"... and bind up after your suspension droops. HOWEVER... in regards to pinion angle, if Rusty's blocks are angle for pinion correction, when you lower the rear of the spring for the flip, and remove the block, the pinion will naturally be pointing more upward than before the flip and may be correct after all... but if not.... shims can be used. METAL shims not aluminum or plastic...

[Iron Horse]

RB,

So to be absolutely correct, you would need to remount the rear shackle support 1.5 " (or so) towards the front to keep it from reverting.

However.....
It looks to me if you cut the bottom out of the OEM box/bracket (remember this is an 80's wag) and weld on a new top plate, that the shackle is now "captured" (because of box type bracket)and unable to revert to it's original position. Whew...Does this make sense? This would *only* work for those that have the box type shackle mount.(?)

BTW, if I remember, the Rusty's blocks were NOT tapered. So what does this now do for the pinion angle? Just dbl. checking, but the pinion angle must match the t-case output angle, right?

Thanks,
Andy

[River Beast]

In respect to "capturing" the shackle... you are correct to a degree... but with lift springs, there is more arch to contend with, thus more pressure. Don't get me wrong...it might work. That's where you have to make the determination if you want to deal with mods you weren't planning on. It does give you a good sense of accomplishment when you finish... :D

As for angle...you should be ok.... and yes... the pinion angle and output angle should be within 1-2 degrees of each other to cancel vibes. A CV could be used if you can't get the angles just right.... that's when I point you to remember what I said before...you have to make the determination if you want to deal with mods you weren't planning on.

Nothing to it but to do it...jsut don't make any permanent changes that you can't reverse.

BTW... there is a small plate that is welded to the bottom side of the OEM shackle box, bracing it to the frame. This will have to be removed and somehow the box will have to be reenforced again to ensure rigidity.

When I fabbed my shackle mount, I removed this plate and made a new one that was part of my fabbed shackle mount and bolted it to the frame... worked out great...

[Iron Horse]

Thanks for the GREAT info and ideas RB. So now I'm thinking that if I fabbed a rear bracket like yours and corrected the pinion angle that I'd be in business. Cool! :D

Thanks,
Andy

[dennis w helt]

hey, i work in a sheet metal fab shop so i make lots of different brackets and such the brakets you need are eazy to fab a total of 10 minutes a piece so i can make them again i still have the patteren dennis

[graham]

Can someone please explain what "pinion angle" is? What has to be concidered when flipping shackles? Is it the angle of the universal joints in relation to the position of the diff and t-case?
I have done the rear shackle flip, keeping the front mount in its original position. No other mods have been done to allow for or compensate for pinion angle. As in these links.
Shackle Flip Page (http://www.geocities.com/ozbearhunter/suspension.html)
Shackle Flip Pic (http://www.geocities.com/ozbearhunter/Before_After.jpg)

[Cecil14]

Pinion angle is the angle of your driveshaft to the yoke on your t-case or differential.

Hey RB, if you could I would love a set of drawings for those brackets and anything else needed for this mod to work. I'm going to do the SOA up front and would like to stay away from blocks. Also thought about getting some 4" rear springs and just raising stuff about 3" rather than 7". hehe

Thanks,
Anthony

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Cecil14:
Hey RB, if you could I would love a set of drawings for those brackets and anything else needed for this mod to work. I'm going to do the SOA up front and would like to stay away from blocks. Also thought about getting some 4" rear springs and just raising stuff about 3" rather than 7". hehe

Thanks,
Anthony<HR></BLOCKQUOTE>

I think you are confused a little... the SOA gives you 6-7" REGARDLESS of springs... just as the rear shackle inversion will get you the same 6-7" REGARDLESS of springs...that's why you don't need blocks with this mod

[Cecil14]

RB - ok, think I got that now. What I mean though is that an option could be to get 4" rear springs and do something else in the rear to gain the additional 3" you would need to cover the SOA up in front.

Would still like to keep everything else open as an option though,

Thanks,
Anthony

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Cecil14:
RB - ok, think I got that now. What I mean though is that an option could be to get 4" rear springs and do something else in the rear to gain the additional 3" you would need to cover the SOA up in front.

Would still like to keep everything else open as an option though,

Thanks,
Anthony<HR></BLOCKQUOTE>

Well...now that you have a 4" spring, you would need a 2-3" block to level it out tpo the SOA up front...or... mod the OEM shackel mont like described above to get 3"...but be careful. Taking the risk of doing this type of mode always turns into more than you bargained for... ;)

[Cecil14]

<BLOCKQUOTE>quote:</font><HR>Originally posted by River Beast:


Well...now that you have a 4" spring, you would need a 2-3" block to level it out tpo the SOA up front...or... mod the OEM shackel mont like described above to get 3"...but be careful. Taking the risk of doing this type of mode always turns into more than you bargained for... ;)<HR></BLOCKQUOTE>

Of course it is! It wouldn't be any fun if it went exactly as planned. :D I would like to stay away from blocks whatever I do and I figured it would be easier to make a 3" mod versus a 7" mod. Could be wrong though, that's why I'm here. hehe

Thanks,
Anthony