Rear Coil conversion

ok I have a 1990 Jeep XJ and im converting the rear from leaf spring to coil spring. i already have a Dana 35 out of a 97 ZJ and the coils. the only thing i need to know is were should i mount mt new upper spring perch and were to mount my new controll arm(im only going to have a 4.5" lift so im going to staying short arm) thanks
-Keep Jeepin

Not to be a jerk, but if you're going to the trouble of mounting control arms, springs, etc, wouldn't it make sense to do it with a better axle?

stoneattic said:

Not to be a jerk, but if you're going to the trouble of mounting control arms, springs, etc, wouldn't it make sense to do it with a better axle?

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X2.

If you stick with it, take a close look at a ZJ or a TJ, and see how they are set up.

X3,on the wall of the garage is the right place for a D35!The housings make great ashtrays!

:dunno: i just figured he picked up the whole rear end as cheap and easier with the coil buckets and arms and everything as cheap as piece meal. I assume he would not waste time making a coil conv and use a d35 ? Please proove me right

well since i didnt say this be for but the dana 35 was FREE and its what i have so im ganna get it in for now and upgrade later and im not ganna run bigger then a 31 on it!! so all the dana 35 joke as funny as they are and i know its not the best axle ever, just give me a brake (lord knows the axle will haha).
-Keep Jeepin

for what your gonna do with it, it isn't really worth the trouble and all the fab.

but, the new coil should mount about where your bump stops are now. and for the upper and lower arms.... you will need to figure that out. there are programs that lit you calculate four links and stuff but since you gonna do something like a zj set up, i would crawl under one with a measuring tape and a pad of paper to sketch out the design. then see if it will apply to your xj's situation. don't forget about the track bar! regardless, more than likely you will have to fab up another x member to mount the arms too. im sure it can be done, but why put all that work into it when you can throw a set of shackles on your leafs and have just as much flex?

dont forget the angles of the arms are probably gonna be jacked up so traction will either be spot on or totally off. i would search around google and other forums for people that have done it this way. most people just do a 4 link or a 3 link.

oh yeah if anything brakes this axle its not ganna be the tires its ganna be the 4.5 storker thats ganna be installed hopefully this springatriot:
-keep Jeepin

come on people.. D35's are awesome. No seriously do some searching. You can pick up a Chrysler 8.25 w/ 29 spline axles for about 150.00 or so.... thats more reasonable. But honestly you're wasting your time w/ the turdy five.

d35 suck even if they are superior 35s? or super 35?

white_elephant said:

d35 suck even if they are superior 35s? or super 35?

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in terms of value, yes it sucks. Just get a used explorer 8.8 with disks for $250-$400 easy! Much much super-ior axle.

If you got a super35 kit on your rig, or already bought one and used it great, just dont go buy one now. there are many thread on swaping in a explorer 8.8, its bolt in no major fab work. Its a no brainer up grade.

The super35 kit still doesnt address the fact that the housing flexes like a wet noodle and the ring gear breaks teeth like a meth addict..

My dana 35 blew the spider gears, on 32's, on fairly flat ground doing a u-turn under throttle.

I see the 35 being a great mock-up axle to upgrade later. But fiqure out how to do the arms will be difficult. But if you can fiqure out how to keep the axle mounts stock then when you do upgrade you can look into one of these
http://www.tntcustoms.com/webv5/reartruss.asp and will make it much easier to swap later.

I say he got it for free... use it to do the setup, then when you find a better axle, just cut off your mounts and put them on the new axle, and it's ready to bolt up.

maybe not the perfect way to do it, but he got it for free, so why not?

Man you don't have any idea of how big the can of worms you're wanting to open here. designing a 4-link coil suspension from scratch is something that has to be right or it will be scary bad on the road, and on the trail. IMHO if you are asking questions on where to mount links, and how to put this together. You have no idea what you're doing, and should either think of just buying a already made kit, take it to a suspension shop that knows how to do what your wanting, or just leave it alone. My suggestion is to just leave alone. If you have ever driven a full coil (4-link with a track bar) vehicle off road you will find they have a funny handling characteristic about them. Personally I don't like it, feels like the ass end is falling out from under it. I'm not trying to be an asshat here, but just trying to educate you on what you're getting yourself into. Designing suspensions form scratch is something that takes know how to do. At the very least if you decide to go though with it get someone that has done this before to guide you through it.

Holy crap guys, you are are acting like this is a friggin bolt-in swap. The rear chassis of the ZJ is ENTIRELY different than an XJ.

Number one, I am using standard ZJ rear coils in the back of my XJ for the current build. The top of the coil is seated on the bottom of the frame rail. With stock ZJ rear coils this perfectly balances out the 8" of lift I have in the front.

Number two...now you've got to find a place to put 4 control arm mounts and a panhard mount on a unibody chassis, in an area that has no reinforcement at all from the factory and very little clearance to work with. The rear half of a ZJ has lots of layered sheetmetal and reinforced/formed bracing much like the front area on an XJ. Considering you're relocating ALL of the propulsive force from the rear axle to a place on the chassis that is single-layered sheetmetal, you will need to do lots of reinforcement and fabrication to have any kind of secure mounting for the arms.

So given the amount of design that *should* go into a project like this, to leave it with the less-than-desireable factory arm configuration sounds like a big waste of time. You will get much better performance out of leaf springs and a traction bar. The ZJ guys hate the wheel recession that the rear short arms give because it requires having the tire off-center in the wheelwell at ride height and lots of retarded trimming to make up for it. Honestly it would probably be an easier project to fabricate a rear 4-link specifically for your vehicle rather than dick around with trying to make a design from a different vehicle work on yours.

lol.... asshat.

I like that.

Im looking for a Dana 44A(i know i have to trush it and skid plate it i know this), i know im going to be under going a huge project but im not trying to go in blind hence the reason i posted this. im doing more research and yeah its ganna be a big project but it can be done. and no leaf with shackles dosent flex as nice as coil.
-Keep Jeepin

You need to see more leaf with shackle rigs, I think. Goatmans leaf sprung rear on his XJ flexes as well as near any coil rig, and better than most of them.

Hella-XJ said:

Im looking for a Dana 44A(i know i have to trush it and skid plate it i know this), i know im going to be under going a huge project but im not trying to go in blind hence the reason i posted this. im doing more research and yeah its ganna be a big project but it can be done. and no leaf with shackles dosent flex as nice as coil.
-Keep Jeepin

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D44A?

I have one in my ZJ and can't wait to get rid of it. What a piece of crap. Better get used to limited aftermarket and replacing bearings if you use it a lot.

I still say it's a mistake to try and use the factory geometry. It will be just as hard (if not harder) than building something that will work 100x better.

If you're all for the idea of fabricating all kinds of bracketry and reinforcement on the XJ unibody, why the opposition to making a few brackets for the axle?