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teotwaki

Excelsior!
Just teasing you about the street tires...

I had M/T tires on my Bronco and hated them. LOUD, NOISY, LOUD.

Terrible wear and mileage.

Balanced terribly.

Ugh.

I could take maybe a more agressive tread than the Revos but they are a good compromise for a D-D

PS: if we are teasing then I'll call you PegLeg Woods
 

teotwaki

Excelsior!
lowering the trailer

So I want to look at figuring out some of the details to lowering the height and figured to see what sorts of advice folks might have.

My goal is to further lower the height of the trailer. It has a fairly high center of gravity as well as the top of it sits higher than the tow vehicle (4Runner). That may be hurting gas mileage more than it has to. I have lots of clearance under the axle and the departure angle won't suffer much.

I could go for a spring under setup with the current springs but don't want the ends of the U-bolts getting smashed. I'd like to stick with spring over mounting but the shock mount is already hanging down there anyhow. :) Because the springs in there are providing "lift" I think that going to springs with zero lift is one way to go.

The springs and shocks that came on it look like this:
trailer018.jpg

trailer027.jpg


The springs are Procomp part number with 2.5" of lift:
51323 for Jeep YJ Wrangler rear springs (2.5" lift)
flat length: 45.87"
free length: 42.37"
camber: 7.4"
eyelets: 1.5"
leaf width: 2.5"
leaves: 4
weight: 28.6 lbs
spring rate: 188 lbs/in
The eyelets have red poly bushings and the kit for replacements is 69261


Deaver Springs over in Santa Ana can re-arch them but that is $180. So rather than experiment on the Procomp springs I bought some clean used stock YJ rear springs for $80 and want to try a swap. The overall specs are pretty close other than being "zero" lift: flat length of 45.6" long, with a rate of 170 pounds/inch

One of my questions will be about replacing the shocks. I still need to get the specs on them. They are Monroes if I recall correctly. I'm hoping that I don't have to relocate the mounts at all. But, having lower springs will essentially compress the shocks more and use up some of their travel, possibly bring them closer to bottoming out.

Will I need to add a bump stop to protect the shocks on full compression?

Should I shorten the shackles or is that not needed? As I understand it they need handle the difference between the flat and the free length. That would mean they would swing back and forth enough to handle the spring compression but without going "vertical" at the end of the compression arc.

I also have to find some way to securely hold the body of the trailer up while I drop the axle and swap the springs. Regular car jacks are a bit too short.
 

Ford Prefect

Expedition Leader
I'll warn you...

The STOCK YJ Springs are VERY squishy! Ergo, take it very easy going for a while. It will be much more liable to flop with those springs. This has been a large problem for people for years doing spring over lifts on their YJs. If you search around on jeepforum and the like, you can find lots of info on the concern. Will they flex so much that you hit your tires on your fenders? That could bend the fenders up, and chew the tire up pretty fast too.

If you want to take the previous springs and put them under, there are tons of companies that make u-bolt skid plates for $50.00 or so. The trailer may ride softer on the bumps, but at what cost? I mean if you dump that thing on its side, well that is going to be a world of hurt for you at the least, and may pick up the back end of your toy, which would make it hard to disconnect the trailer and use your own truck to right the chaser.

Just my .02, which is worth about what you paid for it I am sure... ;)

The trailer sure looks nice though, I used a Horizon for the Expo this year, and it was a blast.
 

teotwaki

Excelsior!
I'll warn you...

The STOCK YJ Springs are VERY squishy! Ergo, take it very easy going for a while. It will be much more liable to flop with those springs. This has been a large problem for people for years doing spring over lifts on their YJs. If you search around on jeepforum and the like, you can find lots of info on the concern. Will they flex so much that you hit your tires on your fenders? That could bend the fenders up, and chew the tire up pretty fast too.

If you want to take the previous springs and put them under, there are tons of companies that make u-bolt skid plates for $50.00 or so. The trailer may ride softer on the bumps, but at what cost? I mean if you dump that thing on its side, well that is going to be a world of hurt for you at the least, and may pick up the back end of your toy, which would make it hard to disconnect the trailer and use your own truck to right the chaser.

Just my .02, which is worth about what you paid for it I am sure... ;)

The trailer sure looks nice though, I used a Horizon for the Expo this year, and it was a blast.


I appreciate the info on the "squishiness" of the YJ springs! From the published rates I did not think that they would have been any different than what I have now; 188 vs. 170. I think I also spotted a kit that allowed a spring under but inverted the bolts so that they faced up.
 

Titanpat57

Expedition Leader
Hi Jim,

Looking at the pics it seems it shouldn't be too much trouble to flip the axle to the top. Maybe get a dedicated spring shop involved, as their expertise may save you overall time and money. I would bet you could add a leaf, add bumpstops, and use a shorter shock. Two options I'm considering are the coil springs Tom Foolery used, or actual airbags (or air springs) between the axle and trailer frame.

Either way I bet you'll enjoy the ride a bit better. Does it create any issues dropping the trailer down 6" with the awning brackets?

Murphy's Law never takes a vacation day....good luck
 

teotwaki

Excelsior!
I've been surfing the web heavily and found a good tutorial on shackles at:
http://www.quadratec.com/jeep_knowledgebase/article-93.htm

From what I understand so far, the angle on my shackles is reasonable. I also have found that stock Jeep Wrangler YJ shackles are 4" from bolt to bolt and I think that mine are close to that. Supposedly any addtional length in inches divided by 2 is equal to addtional lift to the trailer.

I'll be beating the suspension topic to death before I make any changes to the current setup :violent-smiley-031:

Besides, it is fun learning about this stuff. :victory:
 

Photog

Explorer
Start with a Spring-Under conversion. Get a set of the "square" U-Bolts, and keep the nuts on top, where they are now. Jamestown Distributors.

This keeps the same spring rate and keeps the nuts on top. Then you only have the shocks to sort out. You may not have to change shocks, depending on how much up-travel you want. The tires might touch the fenders before you run out of shock-length. Then you just need bump stops.

Another options would be to use the factory YJ springs (spring over axle), and add one of the leaves from your ProComp set, to keep similar spring rate, with a lower ride height.
 

teotwaki

Excelsior!
Hi Jim,

Looking at the pics it seems it shouldn't be too much trouble to flip the axle to the top. Maybe get a dedicated spring shop involved, as their expertise may save you overall time and money. I would bet you could add a leaf, add bumpstops, and use a shorter shock. Two options I'm considering are the coil springs Tom Foolery used, or actual airbags (or air springs) between the axle and trailer frame.

Either way I bet you'll enjoy the ride a bit better. Does it create any issues dropping the trailer down 6" with the awning brackets?

Murphy's Law never takes a vacation day....good luck

Thanks Pat!

If I get to where I cannot get this done on my own I'd have no problem with a spring shop helping out. Going with the stock YJ springs is more of a bolt in. Anything after that will involve paying somebody to do some welding so I'd like to get it right the first time.
 

teotwaki

Excelsior!
Start with a Spring-Under conversion. Get a set of the "square" U-Bolts, and keep the nuts on top, where they are now. Jamestown Distributors.

This keeps the same spring rate and keeps the nuts on top. Then you only have the shocks to sort out. You may not have to change shocks, depending on how much up-travel you want. The tires might touch the fenders before you run out of shock-length. Then you just need bump stops.

Another options would be to use the factory YJ springs (spring over axle), and add one of the leaves from your ProComp set, to keep similar spring rate, with a lower ride height.

I need to pull one of the shocks and cycle it to at least have an idea of what it can do. Thanks for the link to the square U-bolts. There must be a tie plate to go on top of the axle too.
 

Photog

Explorer
This link shows the use of the Square U-Bolts.

http://www.thenewx.org/forum/showthread.php?t=5267

The upper & lower plates, used in this thread, were fabricated, but Chevy & Dodge both had plates on many axles, that can be found in the Bone Yards.

The shaft diameter on your shocks looks beefy. Those shocks might be stiff enough to counter any "squishiness" of a factory YJ spring. Just swapping springs is probably the easiest thing to do, and see if it works properly. You might be all done, at that point.

Oh, and I think your trailer is SWEET!!
 

teotwaki

Excelsior!
This link shows the use of the Square U-Bolts.

http://www.thenewx.org/forum/showthread.php?t=5267

The upper & lower plates, used in this thread, were fabricated, but Chevy & Dodge both had plates on many axles, that can be found in the Bone Yards.

The shaft diameter on your shocks looks beefy. Those shocks might be stiff enough to counter any "squishiness" of a factory YJ spring. Just swapping springs is probably the easiest thing to do, and see if it works properly. You might be all done, at that point.

Oh, and I think your trailer is SWEET!!

Thanks for the compliments and inputs!

In that linked thread there is one picture of a pretty nice bottom u-bolt locating plate.
IMG_0451.jpg


EDIT: they are pricey at $139 a set http://ok4wd.com/rock-equipment-u-bolt-flip-plates.html
 
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