Need help fine tuning XJ leaf springs for added weight/accessories

ThePartyWagon

Active member
Hello my fellow ExPo Jeep fanatics,

Hope you're all staying healthy and getting lots of Jeep projects knocked out!

As my Cherokee gets closer and closer to having most major modifications addressed (HA!), I'm finding myself in need of some leaf spring tuning. The Jeep has changed a bit over the years and so has what I typically carry with me. I have no intention of letting this Jeep go any time soon, another DD will be purchased so this isn't going to see as much drive time as it currently does.

The current issue at hand is the factory shackle bottoming out on the rear cross member behind the bumper, severely limiting my shackle swing and suspension travel, also, resulting in an annoying clunk every time I roll over a bump.

I'm currently running a used set of OME leafs with the added leaf for increased spring rate. These have worked well for a long time and they've kept my Jeep at exactly the ride height I like with a slight rake to the front end. I'm sitting around 3.5-4" (I think), running 245/75s and I have no intention of going taller or to a larger tire. I've been able to avoid an SYE and replacement driveshaft by using a transfer case drop and after crawling all over Moab, I will probably keep it this way for a while. Overtime, I've added a roof rack, rear bumper w/ tire swing, awning and a heavy roof top tent so the springs are a bit soft and sagged under the additional weight. The Jeep also leans to the passenger side but I think that is due to the awning and the offset spare tire.

I also carry a National Luna fridge and a variety of camping/fishing gear on most of my trips. All of this combined with my gal and a 70lb dog and we're loaded down pretty heavily on most trips. Also worth noting, this Jeep regularly tows a drift boat throughout the Rockies. I usually try to put as much of the gear in the boat but the XJ feels like it drives better with the boat kept light with gear in the Jeep. I like the slight front rake so the Jeep sits level when the boat is hooked up (boat and trailer shouldn't weight much more than 1000lbs.

There are lots of options out there; another AAL, shackle relocation brackets, new leaf springs, extended shackles, etc. My two primary goals right now are; addressing the shackle bottoming out and increasing the spring rate of the leafs. There will be times when the Jeep is empty of gear and the tent might get taken off during winter so I can pull it in the garage.

As far as brands of components go, I'm pretty well versed in who makes what but I'm always open to suggestions. I'm really not interested in cutting up my factory shackle hangers or using inexpensive parts.

I've used shackle relocation brackets on past XJs, really liked them, really improved my ride but I'm afraid that running SRBs with factory shackles will limit their functionality and I don't want to add height by combining SRBs with longer shackles.

I'm happy to add another OME leaf but I suppose I will still run into the issue with the factory shackle hitting the cross member.

I really like the Iron Rock Offroad 3.5" spring pack with the military wrapped bushings but these are longer than average springs so a longer shackle is needed, meaning more lift. These can also be purchased with an additional leaf.

If this was your XJ, how would you go about addressing these issues? Are there any other good options I have not yet thought of? Any suggestions or thoughts would be much appreciated.

Thanks!
-Morgan

Jeep for reference:
Behind the Reef.JPG

Unloaded w/o tent
XJ rack.jpg
 

Battle

Member
IRO springs are much softer than OME or RE and may sit lower than you'd expect, potentially making the need for a longer shackle a non-issue. They're really good for flexing, but might not be the best for carrying heavier loads.

If I were you, I'd replace my old OME springs with a new CS033RB (not the RA) leaf pack due to the extra load spring and higher rate, and then pair those with 1" boomerang shackles... which is what I literally just did to my rig to replace an older set of RE 3.5" springs with stock shackles. I wanted to match the 4" PAC coils (which the REs did even with stock shackles) but improve ride and flex with a "smaller" leaf back and longer shackle. So far, the OME + JKS shackles match... albeit, the rig is pretty light right now with no front bumper or winch (in the middle of yet another refresh). I used to run 33s and still plan to, just slightly taller (255/85r16s vs 33x10.5x15s).

IMG_20200523_121713.jpg

Once it's all put back together and road worthy, I'm going to see how I like the shackle angle/ride before considering installing no-lift relocation brackets which really would require even longer shackles as you will loose height from installing no lift brackets with the same shackles. The bolt-in brackets also put even more stress on the spring itself, likely accelerating pre-mature wear of the springs.

You would think with just a few moving parts, setting up the rear of these things would be easier but there's a lot to consider haha. Hope this helps - nice rig by the way!
 

Scoutman

Explorer
IMO, I would re-think the RTT. An Eezi Awn Stealth is 90kg =198# of roof load and would do wonders for your stability, safety, and suspension issues. You have one of the better 'overlanding' suspensions with the OME with AAL so instead of trying to 'fix' the rear suspension, work on fixing the root cause for the issue. Please don't take that wrong or harsh but just think about it.

Would a small camping trailer be a better fit? Maybe something that your boat would also strap to? Would running a ground tent or an OzTent be better suited for the 70# dog? An OzTent 4 would only weight 50# and could be placed on the drivers side to offset the pass side lean. Just another suggestion.

You have a super clean XJ and I don't see any issues with most of the other mods you've made. Use that rack for light weight items only such as gear duffels, traction boards, random firewood on your way to camp, etc. Keep in mind these XJ's aren't the burliest rigs out there so if all else fails, maybe pick a vehicle better suited for the gear you think you 'must' carry.

I say this all to follow up with my situation. My 'overlanding' rig is a Dodge Ram 3500 so it has no issue with our standard trip equipment. I also drive a very clean and lightly modified 99 XJ Limited with OME suspension and 245-75-17's so I understand your base vehicle pretty well. I'm very hesitant to add weight where it's not needed and try to keep a different mindset to my XJ as I do to the truck. If we're camping with just me and my son we'll take the XJ and pack light, if we're going as a whole family with all the comforts then it's definitely the truck.
 

ThePartyWagon

Active member
IRO springs are much softer than OME or RE and may sit lower than you'd expect, potentially making the need for a longer shackle a non-issue. They're really good for flexing, but might not be the best for carrying heavier loads.

If I were you, I'd replace my old OME springs with a new CS033RB (not the RA) leaf pack due to the extra load spring and higher rate, and then pair those with 1" boomerang shackles... which is what I literally just did to my rig to replace an older set of RE 3.5" springs with stock shackles. I wanted to match the 4" PAC coils (which the REs did even with stock shackles) but improve ride and flex with a "smaller" leaf back and longer shackle. So far, the OME + JKS shackles match... albeit, the rig is pretty light right now with no front bumper or winch (in the middle of yet another refresh). I used to run 33s and still plan to, just slightly taller (255/85r16s vs 33x10.5x15s).

Once it's all put back together and road worthy, I'm going to see how I like the shackle angle/ride before considering installing no-lift relocation brackets which really would require even longer shackles as you will loose height from installing no lift brackets with the same shackles. The bolt-in brackets also put even more stress on the spring itself, likely accelerating pre-mature wear of the springs.

You would think with just a few moving parts, setting up the rear of these things would be easier but there's a lot to consider haha. Hope this helps - nice rig by the way!

Thanks for the in depth reply. The more I think about it, the more I'm confident that I have inverted these springs on trips where we're towing or heavily loaded. I snapped a few of the factory bump stop bolts when trying to swap them out and I haven't had rear bump stops in a few years. I bet I've inverted these used springs enough that they've been damaged at this point. I like the IRO springs but your remark on their softe srping rate and the fact that they are longer than stock means I'd need to buy SRBs or a longer shackle either way. I may give Dirk @ DPG a call to discuss the OME system and maybe a refresh. Thanks for the insights, your XJ and mine are on pretty similar pages with our builds, nice to have some firsthand experience to compare to. Yours is Chili Pepper Red? Always loved that color!
 
Last edited:

1stDeuce

Explorer
You need to get the bump stops back in there before you do ANYTHING else. And you need to space them down 1-2" from factory location if you're lifted 3-4"

It's not simply inverting springs that destroys them, it's bulldozing them past their yield point, whether that is inverted or just less arched. Flatter springs can bend backwards without yielding, and many stock springs are slightly inverted at normal ride height. With no stops, you've basically allowed the springs to bend farther than they are supposed to. This is bulldozing, and they do not recover on their own. They can be "re-arched" by a spring shop if you have one locally, but it's more of an art than a science. I believe there is a good spring place in Grand Junction CO if you're anywhere near there...

Realistically, OME springs were only intended to be about a 2" lift. That AAL adds perhaps another 1/2" of lift, but was really intended to carry more weight, not to lift the rig further. 3-4" is a LOT of lift for an XJ. (In spring plus block plus shackle territory, IMO...) Given that you believe you are lifted more than the OME springs would account for, I'm guessing you have a longer aftermarket shackle, or blocks... Both are going to make it even easier to over-compress the OME springs, or any other springs for that matter since you have nothing to limit travel but the shocks. In that case, you also risk pounding off the lower rear shock mounts, or destroying shocks...

It is odd that your rear shackles are bottoming on anything if they're the factory shackles. OME usually does a good job of setting the spring length so that the factory shackles won't hit anything throughout the range of travel. Bending too far is not an issue, as the eye to eye distance shortens as you go away from flat in either direction.

I have seen some "boomerang" style shackles that might cure your ill anyway, and they usually offer a little bit of lift, though they do make it easier to bulldoze the springs if you don't reset the stops. It's a good idea to lower the stops by about the advertised lift of the shackle to keep from compressing the springs more than was intended.

I think a refresh, along with a bit of rethinking may be in order. If you have a bit of lean once you've put some new parts at it, or had your current springs re-arched, it can be compensated with a 1/4" or 1/2" shim bolted to the bottom of the spring pack with the centering bolt. With your current setup, it's also possible that you just bent the pass side spring a bit farther, so it has "sagged" more. Swap the rear springs left to right and your lean may be gone... Get some stops on it, and perhaps a set of boomerang shackles to restore a little lost lift and you may find you're good to go.

BTW, if your shackles are stock, there's a decent chance the shackle bolt to frame isn't going to come out. If it doesn't want to come out, I would recommend leaving it and just doing a short block to gain a bit of lift back... That bolt goes into a blind nut in the frame, and you really have to do some damage to get heat on it or to weld it back on if you twist it out...

Good Luck!!
 

ThePartyWagon

Active member
IMO, I would re-think the RTT. An Eezi Awn Stealth is 90kg =198# of roof load and would do wonders for your stability, safety, and suspension issues. You have one of the better 'overlanding' suspensions with the OME with AAL so instead of trying to 'fix' the rear suspension, work on fixing the root cause for the issue. Please don't take that wrong or harsh but just think about it.

Would a small camping trailer be a better fit? Maybe something that your boat would also strap to? Would running a ground tent or an OzTent be better suited for the 70# dog? An OzTent 4 would only weight 50# and could be placed on the drivers side to offset the pass side lean. Just another suggestion.

You have a super clean XJ and I don't see any issues with most of the other mods you've made. Use that rack for light weight items only such as gear duffels, traction boards, random firewood on your way to camp, etc. Keep in mind these XJ's aren't the burliest rigs out there so if all else fails, maybe pick a vehicle better suited for the gear you think you 'must' carry.

I say this all to follow up with my situation. My 'overlanding' rig is a Dodge Ram 3500 so it has no issue with our standard trip equipment. I also drive a very clean and lightly modified 99 XJ Limited with OME suspension and 245-75-17's so I understand your base vehicle pretty well. I'm very hesitant to add weight where it's not needed and try to keep a different mindset to my XJ as I do to the truck. If we're camping with just me and my son we'll take the XJ and pack light, if we're going as a whole family with all the comforts then it's definitely the truck.

I totally understand your thoughts on the tent. The tent is absolutely what put this Jeep over weight. I've run various roof top tents over the last few years but the rack + the heavy tent are an extra 300lbs (ish) and that is what I'm trying to work around. I love the RTT set up, its convenient and quick so its probably here to stay unless I swap it for a lighter weight tent. I rarely sit in camp for more than 12 hours and that's usually overnight only. We're usually getting into camp late, out of camp early and sometimes we don't camp at the same spot again so the convenience of the RTT is tough to beat.

I appreciate the alternative sleeping suggestions but my boat requires a trailer so I'm not willing to give up my ability to use my 2" receiver. I have no interest in wheeling/camping with a trailer either. All good options though.

The OzTent or a Seek Outside Tipi are good options too. I'm happy sleeping on the ground next to the fire, or in a ground tent but most options aren't as convenient as the tent. When I can roll into camp late on a Friday night, pop the tent and be in bed in less than 5 minutes, most other options tend to fall by the wayside. I'd go back to sleeping in the back of the Jeep if it was a little larger. We did that for years but with two of us plus the dog, things got a little cramped. Plus, I had to pull all of my gear out of the Jeep to sleep and reload everything each morning. Not really doable with the fridge wired into the trunk. I don't think I could convince my gal to go back to a ground tent of any sort while car camping, especially in bear country.

I'm not trying to argue, just laying out why I've gone the RTT route and why some of the alternatives aren't ideal for the way we travel and camp. The Jeep is a great light duty vehicle but maybe not the best for everything I do. I'm currently looking for a second vehicle, maybe an LX 470, 100 Series LC, Sequoias, 5.9L Grand Cherokee or even a truck. I'd love to go fullsize truck one day, just not in the financial position to do that right now. Maybe a second vehicle will relieve the Jeep from it's "do-everything" duty.

Thanks for the different perspective here, all good points. Rather than new parts, maybe rethinking the purpose of the XJ is the right path.
 

ThePartyWagon

Active member
You need to get the bump stops back in there before you do ANYTHING else. And you need to space them down 1-2" from factory location if you're lifted 3-4"

It's not simply inverting springs that destroys them, it's bulldozing them past their yield point, whether that is inverted or just less arched. Flatter springs can bend backwards without yielding, and many stock springs are slightly inverted at normal ride height. With no stops, you've basically allowed the springs to bend farther than they are supposed to. This is bulldozing, and they do not recover on their own. They can be "re-arched" by a spring shop if you have one locally, but it's more of an art than a science. I believe there is a good spring place in Grand Junction CO if you're anywhere near there...

Realistically, OME springs were only intended to be about a 2" lift. That AAL adds perhaps another 1/2" of lift, but was really intended to carry more weight, not to lift the rig further. 3-4" is a LOT of lift for an XJ. (In spring plus block plus shackle territory, IMO...) Given that you believe you are lifted more than the OME springs would account for, I'm guessing you have a longer aftermarket shackle, or blocks... Both are going to make it even easier to over-compress the OME springs, or any other springs for that matter since you have nothing to limit travel but the shocks. In that case, you also risk pounding off the lower rear shock mounts, or destroying shocks...

It is odd that your rear shackles are bottoming on anything if they're the factory shackles. OME usually does a good job of setting the spring length so that the factory shackles won't hit anything throughout the range of travel. Bending too far is not an issue, as the eye to eye distance shortens as you go away from flat in either direction.

I have seen some "boomerang" style shackles that might cure your ill anyway, and they usually offer a little bit of lift, though they do make it easier to bulldoze the springs if you don't reset the stops. It's a good idea to lower the stops by about the advertised lift of the shackle to keep from compressing the springs more than was intended.

I think a refresh, along with a bit of rethinking may be in order. If you have a bit of lean once you've put some new parts at it, or had your current springs re-arched, it can be compensated with a 1/4" or 1/2" shim bolted to the bottom of the spring pack with the centering bolt. With your current setup, it's also possible that you just bent the pass side spring a bit farther, so it has "sagged" more. Swap the rear springs left to right and your lean may be gone... Get some stops on it, and perhaps a set of boomerang shackles to restore a little lost lift and you may find you're good to go.

BTW, if your shackles are stock, there's a decent chance the shackle bolt to frame isn't going to come out. If it doesn't want to come out, I would recommend leaving it and just doing a short block to gain a bit of lift back... That bolt goes into a blind nut in the frame, and you really have to do some damage to get heat on it or to weld it back on if you twist it out...

Good Luck!!

Wow, thanks for the in depth response here. Lots more to springs and spring rates than I knew. Sounds like my lack of bump stops have exacerbated my spring issues. The OME leafs have generally been great, no complaints until I've added the tire carrier, rack and tent. I am not going to bother with re-arching, I will either make these work or we'll swap to a new set of springs.

In regard to the block suggestion, I am not running blocks or longer shackles. Everything I've ever read says avoid blocks due to premature spring wear? Would you disagree with that? Maybe its the guys who are articulating and cycling their suspension a lot who avoid them? I guess I'm heavy enough that the shackles are swung to their fullest extent when the leaves are flattened out a bit.

We'll play with the springs and see if swapping them left to right, plus a shackle, gets me to where I want to be. If not, I'll find a more appropriate set of springs. Lots of options out there. Ill do a set of the adjustable DPG rear bump plates at the same time. Time to drill out those broken bolts, one and for all.

Thanks again for the advice!
 

1stDeuce

Explorer
If you put a 1" block back there, it's not going to destroy your springs any more than you already have, but you MUST drop the bump stop 1" also, or you'll be able to compress them beyond what they were meant to do, and that WILL ruin them. Same with a 1" shackle.

In short, springs can only bend so far before you exceed their elastic limit. Beyond that limit, you are literally bending them, and that's likely why you've lost height. Having proper stops keeps you within the elastic zone, where they will just about live forever.

FWIW, it does not appear that the ARB XJ "kit" includes any drop spacer for the jounce bumper. That seems odd, and even stranger that your shackles are hitting. Evidently ARB springs are very near the elastic limit when fully compressed, and you've managed to bend them a bit without proper stops. Their site does say that the rear lift will be about 3", and that's w/o the extra leaf!! That seems crazy high, but I do recall my friend's XJ have a very tail high stance after we installed an ARB lift on it.

Though I didn't see any other complaints about OME springs being a little long, I did see several people with XJ's that had been bumped from behind, and it buckles the body just a bit, causing the shackles to hit the back of the frame pocket. If you can live with another 1" of height, a set of boomerang shackles would stop that. I saw that a set of K10 chevy shackles may provide a bit less lift, and also a bit of clearance... I'll let you google into that... :)

Good Luck!!
 

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