Combining leaf springs?

[88whitemanche]

What's up fellas....

My 4wd leaf springs are starting to sag....

I just picked up a set of 2wd springs....

Has anyone combined the 2 to get a small lift?

Or has luck with getting a better load setting?

[Pete M]

I've made it a habit of adding in a main leaf (with the eyes cut off) as an AAL under the current main.  doesn't really add in any appreciable lift or payload, just helps support the main leaf better (they are known for getting a reverse arch in them over time and use). 

 

based on guessing (cause I can't see what you've got) I would probably use the 2wd main on top, then 4wd main (sans eyes) under it, then mix and match the rest to find the right balance.  be patient, it's going to take some trial and error to get it right.  :thumbsup:

[Eagle]

I've made it a habit of adding in a main leaf (with the eyes cut off) as an AAL under the current main.  doesn't really add in any appreciable lift or payload, just helps support the main leaf better (they are known for getting a reverse arch in them over time and use).

Aux contraire, mon ami.

 

The stock springs (not metric ton) are 3-leaf springs, with an overload leaf. The overload leaf doesn't do anything until the three primary leaves have sagged down to make contact. Functionally, then, we have a 3-leaf spring.

 

Add a fourth leaf and you have increased the load capacity by 33 percent.

 

http://www.therangerstation.com/tech_library/leafspringrate.htm

[Pete M]

that assumes each leaf is identical.  done it thrice.  as long as it's the main leaf you're adding, the change isn't much of anything.  the lower leafs are stiffer and have most of the lift power. 

 

 

having said all that, someone here will undoubtedly have numbers for each spring.  dunno if my stuff will hold up, but it's been my experience with used leafpacks. :thumbsup:

[Eagle]

Actually, I said you gain 33% capacity, but that on-line calculator says it's 43%. It's a fairly simple exercise in structural/mechanical engineering. The lower leaves aren't stiffer than the main. They are the same thickness and the same width. You are mistaking the fact that they are shorter for stiffness, but if you took just the center section of the main leaf, it would be equally stiff as the shortest leaf (ignoring the overload leaf, which is twice the thickness).

 

That said, I support the concept. I've done the second main leaf conversion on two XJs that were severely sagged (and one had a broken intermediate leaf). The first gave me 1-1/4" of lift. It started out sagged half an inch, so the net was 3/4 of an inch. The second had sagged a full inch. The AAL gave me an inch and a half, so it now rides a half inch higher than stock. In both cases, the increase in capacity could be felt just in the firmer ride (which I like).

[Pete M]

yup, everything we're discussing is with using used leaves, and to the OP, that's why we can't give you a straight answer.  you have to try ans see what your particular chucks of steel gives ya. :thumbsup:

[88whitemanche]

Thanks fellas

I'm going to have to try it out....even though removing and installing leaf springs sucks lol

Oh well life of having a jeep and budgeting lol

[Eagle]

Thanks fellas

I'm going to have to try it out....even though removing and installing leaf springs sucks lol

Oh well life of having a jeep and budgeting lol

There is no need to remove the main leaves. I've done the home-brew spring thing twice with XJs and once on my old Javelin race car. I didn't take the main leaf out for any of them.

[Pete M]

 good point!  I change my plan and would reuse the current mains and do it the way that Eagle said.  unless the current mains are cracked or otherwise way more rotted than the new set. 

[87Warrior]

I did it. Stock 4wd pack + 2wd main with eyes removed. Netted about 1.5" of lift over the stock 4wd packs. It also doesn't squat as much with the same load.

[88whitemanche]

I did it. Stock 4wd pack + 2wd main with eyes removed. Netted about 1.5" of lift over the stock 4wd packs. It also doesn't squat as much with the same load.

Nice...did you put any spray or leaf spring lining to prevent from squeaking?

And what clamps did you use to hold or align the leaf spring in place?

[87Warrior]

I painted the springs with POR15 and Slip Plate. I think the slip plate is almost worn off at this point. Still quiet and still flexy. I did add rub pads to the new leaf as well. For the clamps, I simply bent some flat stock steel and bolted it the the leaf in place of the rivet with a flat topped hex bolt and used a 1/4" bolt with a spacer to hold it together.