Lowering a spring over axle rear suspension - Rick ??

Steering, shocks, springs, and brakes.

Moderators: Super Mod, Moderators

Lowering a spring over axle rear suspension - Rick ??

Postby AWD V8 » Mon Jul 24, 2017 10:25 pm

My 6.0 LS swapped Cherokee is now on the road and has already nearly got me into trouble already with local law enforcement :mrgreen:

A few little things to deal with still, but the biggest of these is the rear suspension height, I want it 2" lower.
Image

Aesthetically yes, I'd like it lower, but the main reason is stability. This thing will get tail happy at 40 mph if I punch it. I've already touched the shoulder of the wrong side of the road with it!!! I've got a quicker ratio steering box, yet to install, but that rear end sitting so high is not great when the truck is going sideways while doing 40+

It is a spring over axle, meaning I cannot simply slip a lowering block in there.

* I could move the axle above the spring, but it will be about 8" lower and the axle tube will hit the body.
* I could install a 6" lift spring, and THEN move the axle on top of the spring.
* I could lower the spring perches on the body 6" and then move the axle on top of the spring.
* I could de-arc the leaf springs, but the spring pack is nearly flat at ride height now.
* I could install a 4-link, if somebody gives me the money.

So Rick, I know you are reading this, as a budget project, a 4-link is not going to happen. I'm not really keen on buying new springs and relocating the axle, but I'll do it if I have to.

De-arcing the leaf springs seems the least intrusive but I can't imagine how ti will ride with de-arced leaf springs. I don't have any reference for de-arced springs, never read or talked to anyone about this. You?? Suggestions??

On a side note, the tires 235/55-17s do not hook well with this torque, so I don't know about wheel hop or any other issues. Might be going to the track with it this Friday and see how it hooks there.
Last edited by AWD V8 on Tue Jul 25, 2017 12:06 am, edited 3 times in total.
I'm not old, I'm ripe

99 AWD Jimmy - RIP
'95 AWD Jimmy - RIP
'89 AWD Jimmy - RIP
User avatar
AWD V8
I eat gummy bears when I post.
 
Posts: 1820
Joined: Sat Oct 25, 2008 11:56 pm
Location: Surrey, BC, Canada

Re: Lowering a spring over axle rear suspension - Rick ??

Postby SleeperSS » Mon Jul 24, 2017 11:14 pm

AWD V8 wrote:My 6.0 LS swapped Cherokee is now on the road and has already nearly got me into trouble already with local law enforcement :mrgreen:

A few little things to deal with still, but the biggest of these is the rear suspension height, I want it 2" lower.
Image

Aesthetically yes, I'd like it lower, but the main reason is stability. This thing will get tail happy at 40 mph if I punch it. I've already touched the shoulder of the wrong side of the road with it!!! I've got a quicker ratio steering box, yet to install, but that rear end sitting so high is not great when the truck is going sideways while doing 40+

It is an axle over spring, meaning I cannot simply slip a lowering block in there.

* I could move the axle above the spring, but it will be about 8" lower and the axle tube will hit the body.
* I could install a 6" lift spring, and THEN move the axle on top of the spring.
* I could lower the spring perches on the body 6" and then move the axle on top of the spring.
* I could de-arc the leaf springs, but the spring pack is nearly flat at ride height now.
* I could install a 4-link, if somebody gives me the money.

So Rick, I know you are reading this, as a budget project, a 4-link is not going to happen. I'm not really keen on buying new springs and relocating the axle, but I'll do it if I have to.

De-arcing the leaf springs seems the least intrusive but I can't imagine how ti will ride with de-arced leaf springs. I don't have any reference for de-arced springs, never read or talked to anyone about this. You?? Suggestions??

On a side note, the tires 345/55-17s do not hook well with this torque, so I don't know about wheel hop or any other issues. Might be going to the track with it this Friday and see how it hooks there.


Something's wrong here...both highlighted sections are basically saying the same thing aren't they?
'96 Apple Red SS...
'02 Pewter Blazer 2


U.S.C.G. "So others may live"
User avatar
SleeperSS
I drink used anti-freeze
 
Posts: 727
Joined: Mon Jan 01, 2007 7:29 pm
Location: Spanaway, Wa

Re: Lowering a spring over axle rear suspension - Rick ??

Postby AWD V8 » Mon Jul 24, 2017 11:41 pm

Yes, you are correct. The spring is currently over the axle.

I'll edit my post to correct this. Thanks
I'm not old, I'm ripe

99 AWD Jimmy - RIP
'95 AWD Jimmy - RIP
'89 AWD Jimmy - RIP
User avatar
AWD V8
I eat gummy bears when I post.
 
Posts: 1820
Joined: Sat Oct 25, 2008 11:56 pm
Location: Surrey, BC, Canada

Re: Lowering a spring over axle rear suspension - Rick ??

Postby SleeperSS » Mon Jul 24, 2017 11:51 pm

Care to elaborate on your judicial mis-steps???lol
'96 Apple Red SS...
'02 Pewter Blazer 2


U.S.C.G. "So others may live"
User avatar
SleeperSS
I drink used anti-freeze
 
Posts: 727
Joined: Mon Jan 01, 2007 7:29 pm
Location: Spanaway, Wa

Re: Lowering a spring over axle rear suspension - Rick ??

Postby AWD V8 » Tue Jul 25, 2017 12:21 am

SleeperSS wrote:Care to elaborate on your judicial mis-steps???lol


Well..... after finding a quiet road, away from all prying eyes, I demonstrated to my brother-inlaw what a copious amount of torque can do when applied to the rather small 235 tires. 1st gear was awash, 2nd gear while picking up momentum quickly was converting the rear tires to caster wheels resulting in the lateral stability of the rear end of the vehicle being greatly compromised. 3rd gear, after a brief verbal protest of the tires, ended my charge. Speedo reading about 70 MPH (30 zone). I stood on the brakes as I approached the crest of a small rise in the road, knowing that poor road repairs ahead would mean a rough ride. As I crested the rise, intending to do a U-turn, I saw a black SUV stopped on the shoulder of the road. Not thinking anything of it I checked for traffic behind me and swung the Jeep around. Not quite making the complete turn I had to back up a wee bit. As I straightened out I looked behind me before I pulled back onto the road. The SUV that was stopped on the side of the road was now quickly closing in, and then the flashing lights came on. Of course being the responsible citizen I am I pulled over and put on my best surprised expression. After a minute the officer came to my open window and asked why I made a U-turn when I saw he was a cop. I, in all honestly, said I was avoiding the rough section of road that was just ahead seeing as my exhaust was rear suspension was banging up my exhaust pipe, truth! I told him I had no idea he was in a ghost car, truth. He took my license and insurance and returned in a few seconds and told me to have a nice day! He was a cool cop. A few seconds later to shut down and I'd be in big trouble.

It helps the Jeep not having a loud exhaust, the tires don't squeal, and, I'm an old fart :mrgreen:
I'm not old, I'm ripe

99 AWD Jimmy - RIP
'95 AWD Jimmy - RIP
'89 AWD Jimmy - RIP
User avatar
AWD V8
I eat gummy bears when I post.
 
Posts: 1820
Joined: Sat Oct 25, 2008 11:56 pm
Location: Surrey, BC, Canada

Re: Lowering a spring over axle rear suspension - Rick ??

Postby lowblazin94 » Tue Jul 25, 2017 12:32 am

Lift springs and put the axle on top. Or see if theres leafs from another type of vehicle you can make fit or have someone like Calvert make you some leafs so you can put the axle on top and maintain good handling.
92 S10 Ext cab
385
700r4
User avatar
lowblazin94
TheCowWatcher
 
Posts: 4608
Joined: Wed Jul 20, 2005 8:16 pm
Location: Houston, Tx

Re: Lowering a spring over axle rear suspension - Rick ??

Postby Rickracer » Tue Jul 25, 2017 7:41 am

Going spring under shouldn't be 8", more like 5" or 6", depending on what type spring pads you use, (you could even make your own out of C-channel, :idea: ). You don't want the spring pad any deeper than the centering pin on the spring. You could take some measurements and see exactly where the drop would wind up at. If I could see some pics of the rear spring hangers, I might have some easy ideas there, but one not too expensive solution would be to have the springs re-arched. I even flipped the fiberglass rear springs on an Astro van one time. 8)
Rickracer
ASE Certified Master Automotive Technician (well over 3 decades of experience, :thumbup: )
'93 S10 SB,RC, Comp XR276 Hydraulic Roller, Vortec head 363, 400 + hp, built 700R4, JW 2800 stall lockup converter, 3.73 posi, disc brake, narrowed 8.8 Exploder rear, LS Camaro front discs, Cal-Trac clone traction bars, Best N/A passes to date: 7.76 in the 1/8th, 12.24@109.27 mph in the 1/4, gonna spray it one of these days... :mrgreen:
76 Chevy Vega Drag Car, TWIN TURBO 355, P/G trans w/ brake and JW 4000 stall vert, 4 link back half, narrowed 9", 3.50 gears, 29.5x10.5W ET Drags. Best time9.669 @ 139.79, Latest video: https://www.youtube.com/watch?v=S59riYn ... ata_player
Rickracer
Master Swap Tech
Master Swap Tech
 
Posts: 28798
Joined: Wed Apr 26, 2006 8:02 am
Location: Kissimmee, Fl.

Re: Lowering a spring over axle rear suspension - Rick ??

Postby AWD V8 » Wed Jul 26, 2017 6:21 pm

The axle center is 2-1/2" from the perch mounting surface.
The spring pack is 1-1/4" thick
Image

Image

Image

Image

So if my high school math serves me right, flipping the perch to the bottom of the axle is a change of, 2 x 2-1/5", so 5"
and, the thickness of the spring pack, 1-1/4" is added to that, so a total of 6-1/4" of change.

If I want a 2" drop, I would need to use 4-1/4" lift springs.

Those spring eye bolts are VERY tight. Looks like a winter project to me.
I'm not old, I'm ripe

99 AWD Jimmy - RIP
'95 AWD Jimmy - RIP
'89 AWD Jimmy - RIP
User avatar
AWD V8
I eat gummy bears when I post.
 
Posts: 1820
Joined: Sat Oct 25, 2008 11:56 pm
Location: Surrey, BC, Canada


Return to Suspension & Brakes

Who is online

Users browsing this forum: No registered users and 2 guests