The front leaf spring thread. who's doing it now? what have you learned?

whats up, I have been lurking around since august when I bought an 85xj for a trail rig buildup. I am just finishing p the front leaf conversion, should be finished by next week. Here is my setup...

-I went with a 31 spline 9in in the rear. I hadnt planned on running this axle, but I traded my dana30 and my 35 housing for it. I left it full width.

-Front axle is a 30spline 44 out of a cherokee chief. Its not a disco and has u-joints and not cv's. It is the same width as the 9in, I just need to figure out what to do about the bolt pattern. Does anyone know of a good set of wheel adapters that arent to wide? The knuckles are flat top, so I will be using a highsteer arm on the passenger side for now just to raise the draglink until I get the funds for a new tierod and another arm.

-My front crossmember is 4x4x1/4 in angle (thanks for the idea Brett). I used Slickrock shackle hangers and shortie shackles. For the rear hanger I am using the lower control arm mount. I have the springs hung and center pin to center pin is 30.5in.

The rear axle is in, I just need to get some shims or rotate the perches a few degrees. I also need to pick up a dakota brake line. I have the perches for the front, I just need to weld them on and then I can bolt in the axle. I am using stock waggy springs, I might switch to yj's depending on the stance. I have some 37x12.5x15in SSR that I will be running. I will try to get some pics up soon. The axle should be hung by tuesday and my goal is to have it on the road by next week...
 
BrettM said:
what bolt patern is the 9"? you can change the D44 to 5on5.5, 6on5.5 and 8on6.5 all pretty easily.

The 9in is 5on5.5, so I think I can change it with chevy outers or something like that. I found a list on pirate4x4 I need to dig up again....


I got the axle mounted today, everything looks good. The only thing I am worried about is the shackle angle. With the axle hanging, the shackles are at about 83-87*, with the axle on jackstands, the shackles ride at about 50*, is the angle to great? The shackles are 4.5in center to center, and I am running stock waggy springs, not the 7-leafs. The springs seem real soft, and I would like to keep it as low as I can. Would an add-a-leaf help the angle? The springs arent flat with the weight, they have a slight curve to them....what do you guys think...
 
Thrasher, how much lift do you hope to acheive with this setup? What did you do for lift in back? I have an 86, and I've been looking into doing the leaf conversion. This thread rocks!
 
gump said:
Thrasher, how much lift do you hope to acheive with this setup? What did you do for lift in back? I have an 86, and I've been looking into doing the leaf conversion. This thread rocks!

I am not sure on how much lift I got. I was using a stock waggy pack, but it was to soft and my shackle was at 55+ degrees on flat ground. I took the packs apart this afternoon and removed the bottom leafs and put in add-a-leafs that are for a xj pack. Shackle now rides at about 43-45 degrees which is perfect. With this spring setup, the bottom of the blinker is at 36in. The jeep is sitting on some bald 33in rollers, I dont know how much lift I got but I have plenty of room for 37's...

Kevin
 
got my junk sitting on its tires. Still need to set up the highsteer, get new brakelines, and set up gears but I should be on the trail soon. The tires are bald 33in swapers and the wheels are 15x8 w/4in backspacing. Width is around 78in and wheelbase in now 106. Front shackle rides at 43*....

79768.jpg
 
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BrettM said:
lookin good, but a few things:

-if you put johnny joints in the shackles, you may get too much side to side movement from the axle when you steer. this could be countered by a panhard (trackbar) or hydro-assist.

-steering. I didn't see any in your pics. I sure hope you're running crossover or high-steer, when I was using the stock Waggy inverted T it was scary. also, for steering arms, you will want to get one that is fairly short (i'm using partsmike) or a longer pitman arm so that you get full steering.

-tires/wheels. looks plenty wide to me, but I guess our trails may be pretty different, what backspacing are you using?

-wheel travel. you need to let the leafs break in after a few trails before you can expect good travel out of them.

Steering is high steer, rims are 10in with 4.5 backspacing
 
all upgrades are mods, not all mods are upgrades.

can someone please explain the benefit of front leaves and rear coils, when used togather? I can definately see advantages to having leaves all around, and definately see (different) advantages to having coils all around, and front coils/rear leaves is obvoiously a very good setup. however I'm totally not seeing the point to the front leaf rear coil thing though, unless you're one of those "stock sucks" people.

but what do I know I'm "upgrading" to a "new" engine with 200k on it, I guess we all get off on changing things
 
one of the "rock crawlers" in my area who frequently heads north has leaves on the front of his yj and air shocks on the rear...crazy flex in the rear and yj style flex in the front. He says its better cause he can drive the front where he wants and the rear just follows...I see him lift a lot of weight off the rear sometimes...but it works for him...I think mine with leaves all the way around was really well balanced...
 
Slip Kid said:
all upgrades are mods, not all mods are upgrades.

can someone please explain the benefit of front leaves and rear coils, when used togather? I can definately see advantages to having leaves all around, and definately see (different) advantages to having coils all around, and front coils/rear leaves is obvoiously a very good setup. however I'm totally not seeing the point to the front leaf rear coil thing though, unless you're one of those "stock sucks" people.

but what do I know I'm "upgrading" to a "new" engine with 200k on it, I guess we all get off on changing things
I don't want to get into this too heavily since this has been debated elsewhere and is not the point of this thread.

Leafs in front coils in rear is nice because most axle wrap comes from the rear, so the links prevent that, and like yellowxj said the front leafs provide a lot of stability and once you get them through a section, you can be pretty much sure the rear will flex right through even if it takes a little different line than the front. Most people tend to focus on where their front tires are going since they can steer them, and rarely does the rear follow the same line.

If you look at all the guys the start with 4 leafs (YJs, CJs, Toyotas, Chevys, etc) you'll notice that they almost always link the rear before the front. I recall a poll on PBB about which end to link first, and the majority vote was heavily in favor of linking the rear first.
 
BrettM said:
lookin good THRASHER!


mjlogan88 on PBB just posted this pic of his on my buildup thread:



check it out i'm famous!

went to post it up myself but it looks like i wasnt fast enough
 
helping my friend jason out a bit on his mj build up when I can...had to build it at my house...got a hp44 and 9 inch now and some 35" swampers....I dont know if he's already got pics on this thread or not...
mj20021tt.jpg

mj20014lh.jpg
 
if he's planning on actually wheelin that MJ get rid of those shackles, they will turn into Zs real quick, look for pics on Fordyce of Poomba if you have any questions regarding that.

looks like too much lift to me, but I'll let you make the decision on that one.

how long are the leafs? they look real long, if they're more than 48" you'll probably need either a panhard or hydro assist.
 
BrettM said:
on the street, sure. have you wheeled it? especially in rocks?

yes to both.

Granted I've only had it out for one weekend, but I didnt really expirience any of the negatives that have been brought up about the xj mains.
 
BrettM said:
on the street, sure. have you wheeled it? especially in rocks?

I ran XJ mains in the front, on 40's with hydro assist. The front was welded with full time drive flanges. So I can't say if the panhard would help on the street or not, but in the rocks that thing did flat out awesome.

I ran a 5" long shackle, in the front, and when climbing a tire vertical like up a wall the shackle would fold over and lock on the frame. Despite having a 45 degree forward angle at rest. Mechanical stops fixed that. The other issue was building the xj with the springs angling down at the rear made it really hard to bolt the axle to the diff with correct pinion angle.
 
JJacobs said:
I ran XJ mains in the front, on 40's with hydro assist. The front was welded with full time drive flanges. So I can't say if the panhard would help on the street or not, but in the rocks that thing did flat out awesome.


that's the key right there, can't imagine wheeling without it, even on "little" 35s
 
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