Does anyone have factory leaf spring measurements?

Ncman

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Morganton, NC
Hello,
I have an 87 YJ and am trying to figure out factory specs on leaf spring widths. Here are measurements on mine,

Front leaf springs
Eye on frame center to center 30.5"
Eye at shackle hanger C to C. 31"

Hangers on frame and front bumper are factory and have not been moved. Does anyone have factory measurements on these points? I thought front and rear would both be the same?
 
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Hello,
I have an 87 YJ and am trying to figure out factory specs on leaf spring widths. Here are measurements on mine,

Front leaf springs
Eye on frame center to center 30.5"
Eye at shackle hanger C to C. 31"

Hangers on frame and front bumper are factory and have not been moved. Does anyone have factory measurements on these points? I thought front and rear would both be the same?
YJ springs front and rear are the same. They measure about 46” eye to eye with a centered center pin. Distance between each pin is the same front to rear.

In theory you could turn any one of the four springs any direction on either axle and they would be the same.

You mentioned width, factory YJ springs are 2.5” wide.
 
Ok, thanks.
Let me ask it another way. Where springs mount on hangers at front of Jeep.......measurement is 31" center to center.

Where the other ends of those same springs.... attach to frame rail hangers they are 30.5 center to center.

I thought they were supposed to be the same.
 
Oh' you're talking about the distance between the springs, that IS interesting.
I would have thought the same thing, but these machines are not without their nuances.
Now I'll have to measure mine the next time I have it up on a lift. Curious...
 
Problem is previous owner swapped axles. A waggy front Dana 44 and a 87-89 Cherokee rear 44.

In the front he ground out the diff casing on drivers side and moved perch in 1/2". On the other perch it looks like he never moved the waggy perch in 1/2" like he should have.
I decided to measure center to center on front hangers, rear hangers and leaf pins. I got,

This is for front springs...all center to center

Front hangers 31"
Pins 30.5"
Rear hangers 30.5
 
Is there a forum with lots of YJ owners somewhere that could help with this? Maybe posting their measurements...
Center to center is ~43”. With a straight edge is should be 43 1/8 but I dont have any documentation to back it up.

Depending on whos holding the tape it’s going to vary.
 
They say a picture says a 1000 words....I hoe so.

IMG_20210305_064916.jpg
 
I knew that's what you were asking about, I just don't have the numbers yet.
Mine still has the factory axles and I will post my findings when I take those measurements.
You have peeked my curiosity.

Additionally, are you having an issue that would have prompted you to look into this?
Tracking, alignment, tire wear, death wobble...etc.
 
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I knew that's what you were asking about, I just don't have the numbers yet.
Mine still has the factory axles and I will post my findings when I take those measurements.
You have peeked my curiosity.

Additionally, are you having an issue that would have prompted you to look into this?
Tracking, alignment, tire wear, death wobble...etc.
Hah! Yeah I know, I was just getting frustrated. It seems like I'm the only person who has asked this question.
I bought this Jeep a few weeks ago. Word of advice....
Don't buy a modified jeep unless it's from the modifier.
My problem is wandering on curves. Does fine on straighatways. Checked tire pressure. Was.at 50psi on 35's. Now at 28psi. All steering is like new. Tightened steering box which helped a little. Problem looks to be in the perch mods.
SUA perches had to be moved in 1/2" each because waggy perch placement is 1" wider than YJ. My measurements are
30.5 frame center to center
30.5 pin to pin
31 shackle to shackle
When behind my Jeep left front tire offset from rear. Front right looks correct. In the end I guess tracking is off due to spring set up. Also, there is no sway bar or track bar. Most say I don't need them.
 
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So your issue is something you can see...

So, as promised;
My measurements were all 30.5", all three points.

Do you know about what year Waggy that 44 came out of?
Had to have been a full size, maybe cut down?

Sage advice on purchasing! Sounds like you have bit of a mess on your hands, but you'll get through it!
Only bought mine because it WAS, clean, bone-stock and other than small things, unmolested.
But she had a lot of issues I didn't know about and I'm still wading through them.

No sway or tracks on mine either, because I yanked them.
I've been on a mission to remove the "Car" from this Jeep since I got it.
I'm willing to deal with Off road vs. On road trade-offs.
But I'm used to a Squishy, Squirrely flat-fender w 1-1/2" springs that never had those parts in the first place.
 
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Thanks for the measurements. FSJ 89 waggy front and 87 cherokee rear. Neither axle has been cut. Rear is supposed to be a little narrower than front but not by much. I'm sure I'll figure it out. First I will put new tires on it. My 35" tires are unevenly worn which is attributing to squirrellyness. Next will be alignment.
 
They say a picture says a 1000 words....I hoe so.

View attachment 117259
The 43” measurment I provided is front driver side front spring hanger to driver side rear frame front spring hanger, if that makes sense. I got that from your question, “how far apart are the spring hangers center to center on the front axle?”

A9E15C57-0548-4F51-9F6D-B4C000D773CB.jpeg
 
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Thanks for the measurements. FSJ 89 waggy front and 87 cherokee rear. Neither axle has been cut. Rear is supposed to be a little narrower than front but not by much. I'm sure I'll figure it out. First I will put new tires on it. My 35" tires are unevenly worn which is attributing to squirrellyness. Next will be alignment.
Most would agree a front axle can be up to 1” wider WMS compared to the rear. Helps with turning radius, among other issues.
 
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Front centerpin to center pin is 31” IIRC.

It’s why the 78-79 Ford kingpin Dana 60 is so highly desirable for YJ guys with it’s 31.5” centerpin to centerpin measurement and centersection cast SOA leaf spring mount

Also one reason why guys have to outboard their front springs to run the early Chevy Dana Kingpin 60’s.
The 43” inch measurment I provided is front driver side front spring hanger to driver side rear frame front spring hanger, if that makes sense. I got that from your question, “how far apart are the spring hangers center to center on the front axle?”
Maybe the axle and leaf pads were welded in without regards to the front axle being centered.
Most would agree a front axle can be up to 1” wider WMS compared to the rear. Helps with turning radius, among other issues.
My axle as mentioned is an 89 waggy. From all the swap threads I've read people move the waggy passenger side perch in .5" and same fore the driver's side. Drivers side requires some diff case webbing removal. Also requires drilling a new leaf pin hole .5" inward. The two perches combined make up for the inch difference in the waggy and the YJ.
PO did grind the waggy diff and move it in. Looks like he moved it in closer to 5/8". Looks like he also moved passenger perch in the same distance. 1.25" overall.
I did find two YJ's parked around town and asked to take measurements. They were the same as mine at 30.5 or 30.7 front,middle and rear. Only difference was mine is 31 at front hangers and they are new and tight on original frame hangers.
I am leaning towards the driver's side being correct...or close enough at 5/8" inboard on the waggy axle. I think the passenger perch may have not been moved meaning it's been forced to work...moving my entire axle to driver's side. I have been thinking it was moved because welds don't look perfect. However, if I move it inward then I'll be worse off won't I?
30.7 frame
30 pins
31. Front shackle
This is becoming frustrating.
 
However, if I move it inward then I'll be worse off won't I?
I edited my post to be more clear with less “filler.” Whatever you need to do to get your springs from binding, in a straight line, or to match the center hanger to center hanger measurment would be where I would start.

Are you able to do all the fab work yourself? If not I would find someone familar with leafs or a reputable fab shop/rock crawler shop who is.

If the spring hangers are factory, why not swap in a YJ Dana 30? Sell the 44 to offset the cost of the swap.

Are you hardcore wheeling it? If not and not on a tire taller than a 35”, the high pinion YJ Dana 30 can handle it and be beefed up with plenty of aftermarket support.
 
I can do so
I edited my post to be more clear with less “filler.” Whatever you need to do to get your springs from binding, in a straight line, or to match the center hanger to center hanger measurment would be where I would start.

Are you able to do all the fab work yourself? If not I would find someone familar with leafs or a reputable fab shop/rock crawler shop who is.

If the spring hangers are factory, why not swap in a YJ Dana 30? Sell the 44 to offset the cost of the swap.

Are you hardcore wheeling it? If not and not on a tire taller than a 35”, the high pinion YJ Dana 30 can handle it and be beefed up with plenty of aftermarket support.
I can do hand tool work but don't do any welding these days. Still working on a shop and for now it's just in the dirt.
I think I'll stick with the plan.
New tires, alignment and checking caster angle and toe. Don't want to go swapping axles when this might be just fine after a few tweaks.
 
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