Front shocks are limiting droop, here's my idea, tell me if I'm way off base...

[emr1101]

yea REs rear packs are real stiff, the last thing htey wanted when they designed them was somehting that sagged

 

[emr1101]

Think i paid right around 200 shipped for them. Definitely worth the $$

http://store.jksmfg.com/merchant2/merchant.mvc?Screen=ACOS&Store_Code=JKS01&Category_Code=Coil_Spring

It says $263, how'd you manage to pay $200 shipped??

 

[vetteboy]

once your coil unseats from the top mount, and you're no longer 'pushing' the axle into the ground, its no longer useful IMO...

There's three reasons why I don't buy that argument.

1- as long as you're not maxing the shock or hanging from the limit straps, you've still got the weight of the axle and tire/wheel. Especially with heavy bias-ply, aggressive tires, this might just get you enough forward traction. I'll also throw out there that there's times when my rig feels superbly balanced with a coil unseated an inch or two, and it stays that way until it actually lifts the tire off the ground. Then you get that 'rocking' feeling from the extra weight hanging off that corner.

2- if the opposite side is on the bumpstop, you've got a cantilever action happening at the bumpstop point. We know that the tire will travel more vertically during flex than during straight bump travel, and that extra bit of upward movement translates to downward force on the other tire.

3- lateral traction. If the tire's in the air it offers none; if it's on the ground, again the weight of it + some of the axle can help hold a line or a sidehill.

I've got 4" up and 8" down right now and I've got no reason to tweak that. I have center limit straps to avoid binding out the u-joints, but even with the coils unseated an inch or two nothing binds and it feels great, so it stays like that for now. Keep in mind that's the entire purpose of a tender/zero-rate coil on a coilover anyway; to keep the springs in line when they're unseated off the stops, which happens often.

The counter-argument that most people come back with is "get custom/better springs". To get springs that didn't unseat over the range of travel I've got, they'd be incredibly soft, and I don't want a softer spring rate than what I'm running already. Also, by the last inch or two of travel, the difference between a soft spring and an unseated spring would pretty much be moot anyway. The only other alternative is to limit the droop before the coil drops out, which doesn't appeal to me for the reasons I mentioned before, and honestly seems kind of pointless IMO. As long as you're not binding anything, maxing anything out, and have a decent way to control the coil so that it doesn't exit the vehicle entirely, it's not hurting anything.

 

[no_gamecocks]

FWIW (minor point), some shackles do indeed make contact with the rear bumper bolts... the ones facing in, four on each side. They quite obviously did on mine when I was running the stock rear bumper with the OEM bolts.

 

[TNT]

There's three reasons why I don't buy that argument.

1- as long as you're not maxing the shock or hanging from the limit straps, you've still got the weight of the axle and tire/wheel. Especially with heavy bias-ply, aggressive tires, this might just get you enough forward traction. I'll also throw out there that there's times when my rig feels superbly balanced with a coil unseated an inch or two, and it stays that way until it actually lifts the tire off the ground. Then you get that 'rocking' feeling from the extra weight hanging off that corner.

2- if the opposite side is on the bumpstop, you've got a cantilever action happening at the bumpstop point. We know that the tire will travel more vertically during flex than during straight bump travel, and that extra bit of upward movement translates to downward force on the other tire.

3- lateral traction. If the tire's in the air it offers none; if it's on the ground, again the weight of it + some of the axle can help hold a line or a sidehill.

I've got 4" up and 8" down right now and I've got no reason to tweak that. I have center limit straps to avoid binding out the u-joints, but even with the coils unseated an inch or two nothing binds and it feels great, so it stays like that for now. Keep in mind that's the entire purpose of a tender/zero-rate coil on a coilover anyway; to keep the springs in line when they're unseated off the stops, which happens often.

The counter-argument that most people come back with is "get custom/better springs". To get springs that didn't unseat over the range of travel I've got, they'd be incredibly soft, and I don't want a softer spring rate than what I'm running already. Also, by the last inch or two of travel, the difference between a soft spring and an unseated spring would pretty much be moot anyway. The only other alternative is to limit the droop before the coil drops out, which doesn't appeal to me for the reasons I mentioned before, and honestly seems kind of pointless IMO. As long as you're not binding anything, maxing anything out, and have a decent way to control the coil so that it doesn't exit the vehicle entirely, it's not hurting anything.

I totally agree with all of your reasons and would like to add to #1. Besides the weight of the axle, rims and tires. It is common for a hardcore rock crawler to add water to the tires which will greatly increase downforce.
Even without the water there can be up to a few hundred pounds on the tire with the unseated spring.

 

[tbburg]

TNT: It's also common for rock crawlers to install 1500 LB winches attached to both axles to "suck up" the suspension and limit droop.

And, who in their right mind would run weighted tires in any non-competition situation? Try stopping from 60MPH with 250lb of water in each tire. Or try changing a tire!

 

[Jeepm@n]

Try stopping from 60MPH with 250lb of water in each tire. Or try changing a tire!(quote)

Ah yes the days of the calcium chromate filled tires on the old Air Force cranes. Man I loved changing those tires. They weighed in @ 550-600 lbs depending on the tire size. Glad my job had more to do with operating the crane rather then repairing it. atriot:

Back to topic:
Looks like interference of your shackles is your problem. They are acting like bump stops thus not allowing the spring to compress and flex.

 

[OBXJ]

All in all, great discussion everyone.

I broke out the sawzall and addressed the bolts interfering with the shackles. I'll see if I can find some time to test out the rear flex and report back!

thanks again for all the input!

 

[OBXJ]

It says $263, how'd you manage to pay $200 shipped??

Check around the boards for vendors. I used DC4Wd but sadly, he's no longer in business due to some personal issues that are eating up his time.

 

[vetteboy]

TNT: It's also common for rock crawlers to install 1500 LB winches attached to both axles to "suck up" the suspension and limit droop.

And, who in their right mind would run weighted tires in any non-competition situation? Try stopping from 60MPH with 250lb of water in each tire. Or try changing a tire!

I've got a front axle winch...and yes, it can be a good tool. Aside from limiting droop you can use it in certain situations to stabilize the truck and also help climbing steep stuff.

I don't run any water in my tires. Bias ply 39.5 Iroks + 16" beadlocked steel wheels are heavy enough.

 

[TNT]

TNT: It's also common for rock crawlers to install 1500 LB winches attached to both axles to "suck up" the suspension and limit droop.

And, who in their right mind would run weighted tires in any non-competition situation? Try stopping from 60MPH with 250lb of water in each tire. Or try changing a tire!

The axle winch is to suck the nose down on steep climbs or steep decents, water also helps on climbs because of the lower COG. It's the trails you wouldn't even try thaat they play on.

There are people that weight the tires for non-competition. If you noticed I said "a hardcore rock crawler". They have trailers to haul their rigs.:twak:

I'm sure they are in the right mind, but they run wicked trails that benefit from the added weight.

 

[XJ_ranger]

There's three reasons why I don't buy that argument.

1- as long as you're not maxing the shock or hanging from the limit straps, you've still got the weight of the axle and tire/wheel. Especially with heavy bias-ply, aggressive tires, this might just get you enough forward traction. I'll also throw out there that there's times when my rig feels superbly balanced with a coil unseated an inch or two, and it stays that way until it actually lifts the tire off the ground. Then you get that 'rocking' feeling from the extra weight hanging off that corner.

2- if the opposite side is on the bumpstop, you've got a cantilever action happening at the bumpstop point. We know that the tire will travel more vertically during flex than during straight bump travel, and that extra bit of upward movement translates to downward force on the other tire.

3- lateral traction. If the tire's in the air it offers none; if it's on the ground, again the weight of it + some of the axle can help hold a line or a sidehill.

I've got 4" up and 8" down right now and I've got no reason to tweak that. I have center limit straps to avoid binding out the u-joints, but even with the coils unseated an inch or two nothing binds and it feels great, so it stays like that for now. Keep in mind that's the entire purpose of a tender/zero-rate coil on a coilover anyway; to keep the springs in line when they're unseated off the stops, which happens often.

The counter-argument that most people come back with is "get custom/better springs". To get springs that didn't unseat over the range of travel I've got, they'd be incredibly soft, and I don't want a softer spring rate than what I'm running already. Also, by the last inch or two of travel, the difference between a soft spring and an unseated spring would pretty much be moot anyway. The only other alternative is to limit the droop before the coil drops out, which doesn't appeal to me for the reasons I mentioned before, and honestly seems kind of pointless IMO. As long as you're not binding anything, maxing anything out, and have a decent way to control the coil so that it doesn't exit the vehicle entirely, it's not hurting anything.

my coils unseat like 2" at full droop on each side...

I'll agree that it feels stable at that point...

I just dont 'know' if its ever helped me...

(im still running 1/2 ton junk and 'small' 35's you know )

 

[silverslk]

here ya go.. The bolt for the rear bumper looks like it may be rpeventing the shackle from rotating backwards(and up) What do you think?

You should also insert the lower shackle/spring bolt inside-out. The way you have it I would expect it to be hitting the side of the hitch/frame rail or atleast one of those bolts hanging down.

BTW. Go with 12" BIlstein short bodies and you should be good.

 

[silverslk]

OH and just for info (and a reason to post pics of my heep). Here is my jeep with RE 5.5" on 33's with 10" bilsteins up front using stock lower mounting point and JKS adapter for running regular shocks instead of the ones with stems on top. I am pleased with the up and down travel. I like the go fast stuff so I need both.