Front Shackle Reversal opinions/ideas

[sappy76]

I'm starting to get the itch to make another modification to my Jeep. I'm starting to research a front shackle reversal but I haven't found much information on this mod. I've read all the pros and cons and have a general idea of what is needed, however I haven't found any real good write-ups on do this to an FSJ.

I've read posts where people point to a kit made by T&J Performance Center, but it looks like they no longer offer one. (I've sent them an email looking for more information, but no response as of yet.) Does anyone else make a kit? I have a 4" Skyjacker spring lift on a HD44 axle from a J20 on the Chief with a drop pitman arm.

I'd like to get about an inch of lift out of the reversal and I'd be interested in best location of the front axle (front/aft). I'm leaning toward making this mod and then cutting and rotating my axle tubes to correct my pinion angle and caster. (Both are slightly off adding to a high speed vibration and less than optimal wheel centering.)

Any suggestions/opinions are desired at this point.

Thanks

[fulsizjeep]

We have it on the other white Waggy. It made for a shorter lift and was already done when we got it.

Pix: http://jubileejeeps.org/tech/soaluna

[sappy76]

Flint,

I read that you liked the reversal as far as ride and flex. But apparently it's not enough of an improvement to make this a standard upgrade, correct?

Also looking at the pictures, it looks like the brackets were just swapped without adding any kind of extension to the front mount. I've seen others where a 2" square tube is welded in place to increase the lift. I have a pair of bjs extended shackles that I was thinking about incorporating as well.

[fulsizjeep]

"Probably" to that question.

Yes, it is stock shackles and spring mounts. The flex on this is great. The tires do not travel straight up and down. They move towards the back of the vehicle as they stuff into the fender well and towards the front as they drop down. The front drive shaft is longer than stock.

[CutterN55]

Make sure your drive shaft is good to go with full cycle measurements, becuase when you stuff the wheels as said the axle is going to come up and back and in a hurry. Would be really easy to grenade your t-case if you run out of room for compression of the front shaft. (use a longer slip shaft).

I reversed my whole front springs in a half-cocked attempt at this + a little wheel base stretch when I got bored one day. I was going to drop the front mounts with square tube also as said above. My axles are not centered on the springs, and this was a little wierd with 6" lift springs. I put my shackles back up front. I will get into it again later when I can take my time and do it right.

Another way I thought I saw is to sleeve/reinforce the frame and put the shackles through the frame with a longer shackle. Doing it this way allows a longer shackle, and limits rearward swing. I think a peice of plate steel welded to the bottom of the frame rail would limit forward movement. I don't know if you'd need to drop the front mount or not for this, and it probably wouldn't get you any lift, but the axle would droop considerably more.

Either way you go, gusset the snot out of the front mounts if you decide to drop them. I think the increased side load leverage would be pretty intense on those lengthened mounts and that may be asking for trouble. If you are looking for lift, this is not how I would go about it... just my thoughts, though I hope for more input and/or corrections to what I said.
If I remember Stuka had some good points on this when I asked about it awhile back.

[Billygoat]

I will be doing this in a couple months on Gonzo, I did it a few years ago on a CJ. I will lower the front mounts, but way more than just a hunk of tube under them, I like to drill hole in the center and plug weld a plate in so the center is supported, or more likely cut new mounts out of 3/8" plate, and run a full support between both sides. On the CJ I relocated the rear mounts as well to keep the axle centered in the wheel wells, IIRC the axles are not centered under our front springs on our rigs, so I hope I can simply flip the spring to get it more centered, I have not pulled a tape messure yet, just poked my head under and looked at things. If you are not in a big hurry you could wait till I get started - probably March depending on the weather - and see how it goes for me....

here is a pic of the CJ front end, that is a 2x2x1/4 wall tube running between the 2 sides, and all 3/8" plate mounts (the 2 holes had tow hooks bolted there at 1 time) and 3/16 tie gussets between the 2 sides.

[billyj7175]

I don't have any FSJ shackle-reversal experience, but I do on other rigs (YJ and Samurai, both SPOA). If you setup the suspension to flex, you need to locate the front axle forward (as stated above), so the front tires don't contact the backsides of the fenderwells.

Also, most of the reversal mods I've seen required a double cardon joint on the driveshaft (but again, that was on a long-travel setup), as the pinion angle changes drastically now as the suspension cycles.

Not sure how this would be on a full size rig, but nose-dive when hard braking/descending increased dramatically. Not a big deal on a long wheelbase...but increases the pucker factor on the short rigs.

The up side, was both rigs rode smoother...and the Samurai turned a little tighter , but I think that mostly had to do with his caster than the shackle reversal.

[sappy76]

Also, most of the reversal mods I've seen required a double cardon joint on the driveshaft (but again, that was on a long-travel setup), as the pinion angle changes drastically now as the suspension cycles.

This brings up another question. I've been also kicking around the idea of swapping over to a 700r4 which has a wider transmission pan, and thereby prevents a double cardon joint at the transfer case. Is it possible to put the double cardone at the axle side? Is there a D44 yoke available for the double cardone?

[sappy76]

I have time

... If you are not in a big hurry you could wait till I get started - probably March depending on the weather - and see how it goes for me....

I probably won't get to this until the spring so I may let you take the lead.

[mdill]

Looks like they just moved the shackels to the rear, other than adding some caster, it should work, and it definitly has the K.I.S.S. factor going for it.

We have it on the other white Waggy. It made for a shorter lift and was already done when we got it.

Pix: http://jubileejeeps.org/tech/soaluna

[Billygoat]

If you keep the pinion at the same static angle as it is stock, and the spring points the same elevation from each other, the angle change should not be that different from stock, just it move closer on compression and further on extension, opposite from stock. Now if you move the front spring eye up to the stock mount and rotate the perches on the axle it could do goofy things with drive shaft angle's - can't say for sure without seeing it cycle, toss some lift springs in the mix and all kinds of crazy could happen...

[Ugly Truck Nut]

Mine had it done to it when I got it, not sure of the quality as I didn't get to put too many miles on it. Should clarify that this is the J-20.

[billyj7175]

If you keep the pinion at the same static angle as it is stock, and the spring points the same elevation from each other, the angle change should not be that different from stock, just it move closer on compression and further on extension, opposite from stock. Now if you move the front spring eye up to the stock mount and rotate the perches on the axle it could do goofy things with drive shaft angle's - can't say for sure without seeing it cycle, toss some lift springs in the mix and all kinds of crazy could happen...

Yes...as long as the shackle length remained a stock length...and the spring eye-centering bolts were in the direct center of the spring. I could be wrong, but aren't they offset closer to one end?

I can't honestly verify if the double-cardon is needed...both rigs I helped on, were installing purchased kits, that recommended a double-cardon front shaft, which was installed at the time of the shackle reversal. Neither rig tried it with the stock driveshaft...so who knows...it might have worked okay.

[AlsChopShop]

Yes...as long as the shackle length remained a stock length...and the spring eye-centering bolts were in the direct center of the spring. I could be wrong, but aren't they offset closer to one end?

he's probably counting on the springs will not be flipped around.


just from a geometry standpoint, i would definitely lower the front mount down 3 or 4 inches to keep the springs as close to the stock angle as you can. flint's wag has an incredible angle to the springs. while that might keep it riding nice as the axle moves rearward on compression, i don't think that is the best idea... springs are run relatively flat for a reason. i would also plate the frame to run the shackle mount through the frame. this will keep the springs closer to flat as well as keep the shackle from hanging down and creating a hang up spot.

Al

[rocklaurence]

This was posted recently:
OEM springs with AAL

With 6" ProComp Chevy springs to recenter the axle. I also had to add 6 degree shims.