Front leveling = Rear sagging???

[Scouts Out]

I did a shackle lift on my Scout II I had, I did not like it, way to much body sway/roll, even cross winds made it feel really ugly. I went back took the shackle lift off and did new leaf springs. The longer the shackles the more body sway and roll. All for it for off road it that is where the majority of you time is spent. I put way too many miles on the highway to do longer shackes. With the home made ones, I would suggest some cross supports between the two halves of the shackles to take some twist out of them

[usetosellhummer]

some h2's had driveline, tranny problems after customer lifts. One customer who kept comming in and being a dick caliming it was us and not the lift was very upset after GM rep put a block on his warrenty. Be very careful not to void your coverage. It does happen

[cestwick]

Originally Posted by Scouts Out

I did a shackle lift on my Scout II I had, I did not like it, way to much body sway/roll, even cross winds made it feel really ugly. I went back took the shackle lift off and did new leaf springs. The longer the shackles the more body sway and roll. All for it for off road it that is where the majority of you time is spent. I put way too many miles on the highway to do longer shackes. With the home made ones, I would suggest some cross supports between the two halves of the shackles to take some twist out of them

I guess I do not understand how a shackle lift raising the truck an inch and a half could effect ride quality if you still have same shocks, sway bar, springs, ect...

[Ipedog]

Okay, I took some quick measurements and with 315's and 2.5 turns on the t-bars:

Front Bumper = 35"
Rear Bumper = 31"
Point A = 12.5"

I didn't measure under the skid as it's too damn hot and Reed (my 3 y/o) didn't have the patience.

I appreciate the help Cestwick and look forward to seeing the pics!

[evldave]

Originally Posted by cestwick

I guess I do not understand how a shackle lift raising the truck an inch and a half could effect ride quality if you still have same shocks, sway bar, springs, ect...

A shackle lift will likely cause more pivot for the leaf springs. Since suspension stiffness is a combination of everything you mentioned (shocks, sway bar, etc) plus the shackles, changing anything will affect stiffness. If you think of the leaf spring bolt swinging through an arc (with the top bolt stationary, but acting as a pivot), a longer shackle will allow more swing (longer arc). Since it allows more swing, even when driving on pavement, if nothing else changes, a longer shackle will result in the suspension system having less stiffness (because ever part moves all the time, more allowed movement=more motion=less stiffness). A less stiff suspension will result in a softer ride, but will allow more sway and susceptability to crosswinds.

I can verify this because it's common for XJ owners that offroad to get stiffer springs (I used Rubicon Express 4.5" lift springs) and eliminate the sway bars. If the leaf springs are stiff enough, you can completely get rid of the sway (but don't get into an accident or try and corner too fast!). Why do this? More flex offroad.

I've also noticed on my H3 that now that my stock shocks are getting toasted (too many gravel/washboard roads) my H3 is a lot more likely to lean over in the wind. Having a big roof rack doesn't help, but it shows that any component of the suspension can have a dramatic affect on driveability. Really there's no way to accurately predict exactly how much of a difference until you try.

[cestwick]

Pics of truck on test track with extended shackles. Fully tucked, fully extended, articulated spring and shackle.

All this talk about lifts and adjusting the torsion bars I am kind of supprised noone has been talking about sway bar disconnects.

[evldave]

Originally Posted by cestwick

Pics of truck on test track with extended shackles. Fully tucked, fully extended, articulated spring and shackle.

All this talk about lifts and adjusting the torsion bars I am kind of supprised noone has been talking about sway bar disconnects.

Pics look good. Seems like it might be a good idea to put a support bar between the two sides of the shackle? It looks like it deflects and a support bar might prevent any problems.

Also, on the front IFS, would a sway bar disconnect really matter? Seems like suspension travel would be limited by the upper & lower arms, not the sway bar (like in a SFA).

For the rear, might be a good idea, when you flex out the rear suspension, does the sway bar limit travel down or is it the leaf springs. W/longer shackles, the sway bar might become the limiting factor (or shocks). I guess I have to get the hummer out and flex the crap out of the rear and see.

[cestwick]

Originally Posted by evldave

Pics look good. Seems like it might be a good idea to put a support bar between the two sides of the shackle? It looks like it deflects and a support bar might prevent any problems. If you read all my preveous posts I stated that I was planning to put a tie bar in but wanted to wait to see how they fit and handled before I welded a bar in.

Also, on the front IFS, would a sway bar disconnect really matter? Seems like suspension travel would be limited by the upper & lower arms, not the sway bar (like in a SFA). I was talking for the rear. Front has travel limitations as we all know.

For the rear, might be a good idea, when you flex out the rear suspension, does the sway bar limit travel down or is it the leaf springs. W/longer shackles, the sway bar might become the limiting factor (or shocks). I guess I have to get the hummer out and flex the crap out of the rear and see. The bigest limiter is the shock (I have new longer ones on order from BDS) but if we start flexing these more then factory they are going to be another factor.

Only thing I am trying to do is level the truck and give it a hair more lift in the most cost effective manner. When all is said and done I should have an inch or 2 over stock, level truck, better articulation in rear, and the same relative ride quality for under $200.