Jeep XJ or Chevy S10 Leaf Springs

[KCStudly]

I have read here and on other build oriented forums that some prefer to run a 3500 pound axle and either Jeep XJ or Checy S10/GMC Sonoma leaf springs.

The idea being that the heavier rated axle has bigger wheel bearings and is more robust for off road duty; and that the automotive leaf springs are longer, and therefore more subtle than the standard shorty trailer springs. This makes sense to me and rings of the voice of experience, so I would like to go this way, too.

My questions are does anybody know what these leaf packs have for spring rates, and how many of the leafs out of the pack are typically used to acheive a particular rate? I had a Sonoma and it definitely had multi leaf packs, and I assume that the XJ springs are also multi leafs.

I think I have a link to the dimensional info for the S10 springs (not the rate info), but can someone lead me to good dimensional info on the XJ springs, width, length, pin location front to back, eyelet bolt diameter, etc.?

I know that the Randy's Off Road XJ springs are very popular with the 4x4 crowd (I have an '03 TJ and read a bunch). Anybody have the details on these or tried them on a tiny camper?

The computer model of my build shows a current weight of about 780 lbs, without suspension, windows, and a bunch of other things. I would be completely satisfied if the whole thing, all up, loaded down with camping gear, personal items, cast iron cookware, cooler, water, sporting goods, axe, shovel, etc. came out at or below 1500 lbs. I suppose 1200 lbs might be a low end number, but the high end could be more than 1500 lbs (I really need to start weighing things to get a better idea on all of the extras on my "To Bring With"" list. )

Any advice?

My build (link in signature) will be fairly rugged for rough 2 track off road capability. It will have higher ground clearance than a typical tear, a full perimeter frame, home made swivel coupler, beef axle and TV matching 31 inch Nitto AT tires on ARE Mojave teflon coated rims. Even though it will have all of these off road features, it won't be super hardcore. It will have hybrid construction, but is still more of a foamie design than a tradtional or pure off road, so I decided to put my build thread over there in the foamie section.

[KCStudly]

(the sound of crickets.....)

[working on it]

I don't know anything about the Jeep springs, but I had an '86 S-10, and recently saved a PDF file of specs on it. The rear springs were rated at 1150 lbs. each, much more than any teardrop could need. Have you considered monoleaf Chevy II springs from '62-'67? They're not as stiff as S-10 springs, are pretty long without excessive arch (when under load), and can be bought for around $200 a set. I was considering them for a scratch-built trailer (assuming I ever finish my first TTT).

[KCStudly]

Thanks. I'll include Chevy II and Camaro/Nova mono leafs in my research. Hope I can find some that aren't too out of whack with std trailer leaf spring pricing. The added capability and "cool" factor may not be worth the added expense in the end. The std trailer springs are fairly affordable, so that alone could weigh heavily on the final decision.

[angib]

When picking the suspension for off-road trailers, some folk do seem to think that they should fit what works well on four-wheel off-roaders. So for example, softer springs will give a four-wheeler the greater axle articulation that serious off-roaders want/need.

However there is a fundamental difference between trailers and four-wheel trucks - the trailer sits on only three points, two wheels and a coupler, so axle articulation means absolutely nothing at all. It's not that it doesn't matter, it doesn't even exist.

So the only reason for softer, long-travel springs is to reduce the shock loads from the wheels hitting bumps. That may be a good idea, but I'm not sure it's worth going to a lot of trouble to achieve.

[KCStudly]

I understand and agree with you Angib.

Actually, I had read all about the 3-point articulation subject here, of course! That's why I am building this...




Soaking up bumps more softly is what I am after with the springs, and will most likely be adding shocks once I get the suspension ride height set. (Kinda hard to model shock mounts when you don't know where they are going to be.)

I realize that spring rate, load rate, and actual load are all different spec's (http://www.eatonsprings.com/rate.htm), but within that context, it is my understanding that a longer spring will ride softer than a comparably rated shorter spring. It may come down to the simple reason that the spring eye is further from the axle and therefore the effective "swing arm" length is greater, meaning that the axle travels in less of an arc with less component of a bump's force (vector) transferred longitudinally. (It may be there are other benefiting factors, too, but I'm not sure what they might be at the moment, just what I've always heard. )

HEY, would you look at that! Seems as though we now have automatic spell check right in the post composition screen! Love it. Mike sure has been busy making this forum shine. Thanks Mike.

[elmo_4_vt]

Personally, I would use something from a junk yard. On my last trailer, I used Ford Ranger springs, and they worked wonderfully. Heading down gravel forest service roads, you could see the axle moving a few inches up and down on even small bumps/holes, where normal trailer springs only have 1-2 inches of Total compression. They definitely provided a MUCH smoother ride on rough roads. Even more so than my truck sometimes. On my new trailer, I'm going to have to use something more heavy duty because of my weight (probably 2500lbs loaded), so I'm thinking I'm going to try a pair from an F-150 or Bronco. Good part is, from a junk yard, you can usually take things back and try different ones without incurring much additional cost.

Don

[mikeschn]

HEY, would you look at that! Seems as though we now have automatic spell check right in the post composition screen! Love it. Mike sure has been busy making this forum shine. Thanks Mike.

Are you sure that's not coming from your browser? What are you using? Firefox? Chrome? I believe both have built in spell check!

Mike...

[KCStudly]

Oh, yep, you are probably right. That post was from the desk top upstairs running Firefox. At home I am usually downstairs on the net pad running Explorer. Definitely need to change the net pad as it does not have any spell check onboard that I can tell (sometimes I sneak onto my comcast on-line e-mail and us that for word processing, but that is kind of butch).

Thanks anyways Mike. Love this site!!!

[mikeschn]

Oh, yep, you are probably right. That post was from the desk top upstairs running Firefox. At home I am usually downstairs on the net pad running Explorer. Definitely need to change the net pad as it does not have any spell check onboard that I can tell (sometimes I sneak onto my comcast on-line e-mail and us that for word processing, but that is kind of butch).

Thanks anyways Mike. Love this site!!!

Mike...

[Martiangod]

Lot of the Ranger guys who do alot of off roading switch out the rear springs to longer Chev 1500 springs for more travel and smoother ride

[KCStudly]

Thanks, Martian.

I'm sure I could slap any old leaf spring under there and mess with different numbers of leafs and stuff, but what I was really hoping for was either someone with experience with a specific make/model/number of leafs set up in a similar weight application. That way I could narrow my search and avoid a lot of experimentation.

Sounds like plenty of people have used light weight automotive springs with acceptable results (Ranger, S10, XJ, C1500, TypeII/Nova/Camaro mono's, Toyota truck, etc. ....well maybe the Nova's weren't actually used, just pondered).

Need to do more research...more...research. "Damn it Jim, I'm just a country doctor!" - Dr. Leonard "Bones" McCoy

[Martiangod]

An Ausi build with XJ springs
Pretty good write up

http://jeep-xj.info/Trailers.htm

[KCStudly]

Thanks Martian, Yeah I had actually found that site on a web search this morning.

Good read. Guy is pretty well obsessed with his Cherokee. Lots of mods.

[angib]

Yeah, long springs will always be softer than short springs, so truck springs will ride better than trailer springs.

I've never been to Oz, but I think they have a lot of washboard dirt roads and those are probably the most extreme surfaces to tow trailers on - big rocks taken slowly are less problem than washboards taken at speed.