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  #1  
Old 09-02-2009, 11:50 AM
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bearfacedkiller bearfacedkiller is offline
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Not enough flex!!!?

Years ago I put a Rusty's six inch lift on my jeep. The lift came with 6" front springs and 4" rear springs with a 2" block. In about a year the front lost 2 inches so I ditched the rear block. This was when they first came out with the 6" kit and I understand they are different now, so not to bash them. I lived in New York then and pretty much just played in the mud. Now I live in Colorado and want to do some more crawling. I have been beating on my 97' tacoma on 32's alot this summer and it flexes better than my jeep. I figured my springs would flex ok but the trails at home didn't really test it and I didn't really care as it was a daily driver too. Now it is going to be a trail rig but I plan on driving it to and from the trail.

So, I tried to flex it out in the driveway with a hi-lift since I dont have any exhaust or driveshafts. I want it to flex very well and think I need different springs. Is this a disapointing amount of flex?

I jacked up the rear right tire so it was about 3.5 inches off the ground and put a jackstand under it.




Then I started to lift the front left tire and it only got about 7 inches off the ground and the other rear tire came up.






So I want this truck to flex like crazy and I am nowhere close. I also want my truck much shorter. I have a 3" body lift that will be difficult to remove with my sm465. What springs near stock height flex the best. I am willing to cut as much fender as I can as this truck will be a choptop eventualy and performance is what matters.

I like the idea of the 63" chevy springs and stretching my wheelbase even if it means modifying the rear wheelwell. How much lift/drop from stock would those net if I kept the front hanger position and moved the rear hanger back on the frame.

My steering setup wont allow any relocation of the front springs. Are stock springs my best bet.

I know the overload is hurting it as well. Could I just remove that and maybe a couple of other leaves to get more flex.

Arghh! Now I'm thinking while I type. Bottomline: My truck is to tall and I want lots of flex. My 3" bodylift is needed to clear the 465 or alot of mods to the floor are needed. It will likely go down to a 2" but not sure, still leaving me to tall. I think really flexy stock height springs with the SOA and the body lift would be great. Plus my front driveshaft sits at a static 28 degrees and losing 4" would drop it to 20 degrees if my trigonometry is correct.

I guess I didn't ask any questions but was just looking for advice and or opinions. Is this not enough flex? Could I make these flex better? What leaf springs flex the best? If you wheel hard trails in CO is my truck too tall? Do you want to give my some free stock springs?
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1985 GW: stock springs, SOA/SF, 3 inch body lift, d60 w/spool, 14ff w/detroit, 4.56 gears, 360/465/205 w/twin sticks and 40's.

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  #2  
Old 09-02-2009, 12:26 PM
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Chevelleguy Chevelleguy is offline
 
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First of all, I have never seen anyone flex a vehicle with a jackstand under the rear axle. That is effectively narrowing your track width which is making it easier to lift the drivers rear tire. Put both tires on the ground and do it again and I bet you will get much better results. Mine flexes WAY better than that with 6" springs.
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  #3  
Old 09-02-2009, 12:33 PM
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Dmntxn77 Dmntxn77 is offline
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6" springs are a flex killer...

If it is taller than you want it to be right now, then just put some stock springs up front with 63"s in the rear. You will need to modify the rear suspension again since 63"s are taller than stock springs. I would just inboard the springs to the frame rails and adjust the mounts to level it with the front.

The body lift will give you a bit more tire stuff room but quite a bit of trimming will still be required...
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  #4  
Old 09-02-2009, 01:01 PM
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onesunJ10 onesunJ10 is offline
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x2 on using a different method for flexing.

63s are played out. I've become a big fan of F150s. They measure 57 inches eye to eye, but are offset. The split is 25in front eye to center pin and 32in center pin to rear eye. They flex pretty well.

Longer shackles might help, too.
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  #5  
Old 09-02-2009, 02:09 PM
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loose(remove) the 2nd spring under the main leaf! it will help flex more.i am not sure how much,but it should show some improvement.
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  #6  
Old 09-02-2009, 02:46 PM
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j20brett j20brett is offline
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You can remove the very bottom spring also. Its the overload, so not needed for offroading. And as said above, remove jackstands. Not safe #1 and it reduces the lever length that is your axle.
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  #7  
Old 09-02-2009, 02:52 PM
FSJ Guy FSJ Guy is offline
 
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Quote:
Originally Posted by Chevelleguy
First of all, I have never seen anyone flex a vehicle with a jackstand under the rear axle. That is effectively narrowing your track width which is making it easier to lift the drivers rear tire.

I will disagree with you on this one. All it's doing is changing the amount of force on the jackstand. The flex is all the same, since you haven't (obviously) changed the position of the springs. That's where the force is being relocated to (by the axle.)

Think of lifting it by hand. It would be EASIER to lift the TIRE vs. grabbing the axle somewhere between the tire and the middle of the axle due to leverage.

BUT, the force acting on the spring remains the SAME because the location of the spring hasn't changed.

That said, 6" lift springs are pretty stiff. If you think that flex is bad, try flexing an M-715!!!
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  #8  
Old 09-02-2009, 03:15 PM
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duncanstives duncanstives is offline
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Stock springs, BJs 1in longer shackles front and 1in blocks with stock spings, shackle flip and inboarded to the rails in the rear... Give you about 8in lift over stock and GREAT flex. Drop the body lift to 2in and you will be ruinning 10in or so over stock... Trim the fenders if thats not enough (not sure what the tire size is). Lift springs just don't flex very well.
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  #9  
Old 09-02-2009, 05:37 PM
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Stuka Stuka is offline
 
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I have an original set of rusty's 6" springs as well (they used to belong to blt2krl). I never did lose any height out of them, but they flex quite well. Not a super smooth ride, but I can get the front tire up about 30 inches before the rear tire tires rubs the fender flares.

If your rig has been sitting, or only driven ont he street, I would bet your springs are rusted up. Being in CA, mine have no rust at all really. That rust basically welds the springs together and prevents them from moving the way they should.

But with all that said, an SOA with flat springs will flex and ride a lot nicer.
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  #10  
Old 09-03-2009, 11:47 AM
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orangecherokee orangecherokee is offline
 
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6" lifts are too stiff from what I've seen. I run a 4" and remove the 4th leaf. Mine flexes ok but it could be better. If I ever recover from my house purchase I'm going to change them out or link it.
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Quote:
Originally Posted by Topgun2mo
I would think boxing would limit the amount the frame could flex over obstacles which I think IMO would be a bad thing. I would think you would want all the articulation possible.
Quote:
Originally Posted by johnny019
I'm not saying lockers don't improve the performance of your rig, just that they're overrated.
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  #11  
Old 09-03-2009, 12:04 PM
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Chevelleguy Chevelleguy is offline
 
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Quote:
Originally Posted by FSJ Guy
I will disagree with you on this one. All it's doing is changing the amount of force on the jackstand. The flex is all the same, since you haven't (obviously) changed the position of the springs. That's where the force is being relocated to (by the axle.)

Think of lifting it by hand. It would be EASIER to lift the TIRE vs. grabbing the axle somewhere between the tire and the middle of the axle due to leverage.

BUT, the force acting on the spring remains the SAME because the location of the spring hasn't changed.

That said, 6" lift springs are pretty stiff. If you think that flex is bad, try flexing an M-715!!!

He is stopping the test because the drivers rear tire is lifting off the ground. If he removes the jack stand, it will effectively lengthen the lever (axle) and put both tires back on the ground so that he can continue with the flex test. Picture it in reverse, if he moves the jack stand closer to the center diff, the left rear tire would come off the ground even sooner.
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10$ NP229 fix http://www.ifsja.org/forums/vb/showthread.php?t=2520
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  #12  
Old 09-03-2009, 12:08 PM
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bearfacedkiller bearfacedkiller is offline
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I am going to put stock springs on it with longer shackles. I gave mine away along with my stock axles when I moved to Colorado to a friend. So I called a few junkyards and there are some springs around here for about $30 a piece. The u-pull has an 87 wagon so I am going to check that out. This is going to bring my center of gravity down alot and and should help with my front driveshaft.


SOA, stock springs, longer shackles, a body lift and a few sawzall blades is the route I am taking to clear the 40's.

I want alot of flex and this should do it.
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1985 GW: stock springs, SOA/SF, 3 inch body lift, d60 w/spool, 14ff w/detroit, 4.56 gears, 360/465/205 w/twin sticks and 40's.

I really am going to get this thing done soon so I can drive it!!!!!!!!!!!!!!
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  #13  
Old 09-03-2009, 12:09 PM
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Murphy Murphy is offline
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Quote:
Originally Posted by orangecherokee
6" lifts are too stiff from what I've seen. I run a 4" and remove the 4th leaf. Mine flexes ok but it could be better. If I ever recover from my house purchase I'm going to change them out or link it.
4th leaf from the top or bottom? Did it also improve the ride quality or loose any overall height of the lift?
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  #14  
Old 09-03-2009, 09:19 PM
FSJ Guy FSJ Guy is offline
 
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Quote:
Originally Posted by Chevelleguy
Picture it in reverse, if he moves the jack stand closer to the center diff, the left rear tire would come off the ground even sooner.

Gotcha. Now it makes sense. Must've dozed off one one of my classes on forces and levers.
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  #15  
Old 09-03-2009, 11:39 PM
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bearfacedkiller bearfacedkiller is offline
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Just to clarify, I only put the jackstand under the rear axle because the high lift with a Lift Mate attachment which has two hooks to grab the rim was getting close to maxed out and it was about to kick out so I cheated a little and jacked the opposite tire up so I could max out the flex. So I figure that with the 7+ inches in the front and 3+ in the opposite rear tire is about the same as the front tire being about 11 inches off the ground. Seems pretty bad to me. I want stock springs but with the wag clearance might be an issue with just an SOA and 3" body lift to clear 40's. Might have a line on a 77 cherokee though and could just start switching everything to that. Hmmm.....
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1985 GW: stock springs, SOA/SF, 3 inch body lift, d60 w/spool, 14ff w/detroit, 4.56 gears, 360/465/205 w/twin sticks and 40's.

I really am going to get this thing done soon so I can drive it!!!!!!!!!!!!!!
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  #16  
Old 09-04-2009, 12:54 AM
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wickedwagon767 wickedwagon767 is offline
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On the stock springs with the shackles mounted forward in the stock location, I've seen a lot of guys bend the main leaf of the springs. There is a lot of force created by the 39.5" tires when you take an obstacle head-on

I recommend bringing at least 1 spare stock spring pack or a stock main-leaf on trail runs just in case

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  #17  
Old 09-04-2009, 01:18 AM
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Gearhead 1990 Gearhead 1990 is offline
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I bet it would flex way more than that if you were in an actual off road senario..... if you want TONS of flex go with something like 52'' chevy springs.....
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  #18  
Old 09-08-2009, 07:16 AM
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orangecherokee orangecherokee is offline
 
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Quote:
Originally Posted by WaveHunter
4th leaf from the top or bottom? Did it also improve the ride quality or loose any overall height of the lift?

4th leaf from the top. it's the smaller leaf. springs will settle over time so you lose at little with wear but for the most part I didn't notice any loss.
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Quote:
Originally Posted by Topgun2mo
I would think boxing would limit the amount the frame could flex over obstacles which I think IMO would be a bad thing. I would think you would want all the articulation possible.
Quote:
Originally Posted by johnny019
I'm not saying lockers don't improve the performance of your rig, just that they're overrated.
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