International Full Size Jeep Association
Home Forums Reader's Rigs Tech Library Trail Stories FSJ-List
International Full Size Jeep Association  

Go Back   International Full Size Jeep Association > Tire Kickin' > Off-Road FSJ Tech

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 02-22-2009, 06:50 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
Front springs in the rear, can it be done?

Well my bed is coming off and I'm going to make some sort of flatbed for my truck. I was planning on cutting off what little extra there is on the rear of the frame to try and gain as much departure angle as possible when I do the shackle flip when I came up with an idea. If I was to use a set of stock front springs in the rear and then move the hanger that is in the very back into the right spot it would help with quite a few things. It would move my rear axle forward about 4 inches helping my break over angle slightly. It would make the very rear shackle hanger 7 1/2 inches closer to the center line of the wheels giving me a far better departure angle.


Has anyone ever done this? If no one has does anyone see any problems with this? I won't have to worry about where my rear wheels are in the fenders because I'll be making my own bed. The only thing I can think of would be that the shorter springs might not flex as well, but the better angles should compensate for that.


Any input or ideas?
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #2  
Old 02-22-2009, 07:19 PM
Elliott's Avatar
Elliott Elliott is offline
Cowboy Up
 
Join Date: Jun 22, 2002
Location: Pilot Point, TX
Posts: 12,704
You may gain departure angle but it will cost you flex as the frt springs are shorter. 4-link and coil it if you want all that.
__________________
*** I am collecting pics and info on any factory Jeep Dually trucks from the J-Series at the new Jeep Dually Registry.
***I can set you up with hydroboost for your brakes: http://www.ifsja.org/forums/vb/showthread.php?t=106056
Reply With Quote
  #3  
Old 02-22-2009, 07:44 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
So you think losing the flex is not worth gaining the departure angle? I don't do any rock crawling, I do alot more trail riding style offroad and I end up dragging the rear end in stuff like creek beds all the time.


I don't really know if its a good idea or not. I will just already be making new rear hangers and bed so it wouldn't be hardly anymore work to go ahead and use different springs. If I did do it with front springs and move that hanger the 7 1/2 inches forward I could cut off nearly a foot of frame.

I really don't know anything about 4 link systems and would like to just stay with the leaf springs. If that means having to stay with the longer rear leafs thats fine.
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #4  
Old 02-22-2009, 07:53 PM
Elliott's Avatar
Elliott Elliott is offline
Cowboy Up
 
Join Date: Jun 22, 2002
Location: Pilot Point, TX
Posts: 12,704
Well, you can try it and see. I think Jeep rear springs are pretty stiff as they are. I'll be putting 63" GM springs in my offroad rig and for departure angle I lifted it bigtime and run 40" tires.
Do you have a lwb? I cut 12" out of my J20 frame under my '65 truck and moved the axle forward 12".
__________________
*** I am collecting pics and info on any factory Jeep Dually trucks from the J-Series at the new Jeep Dually Registry.
***I can set you up with hydroboost for your brakes: http://www.ifsja.org/forums/vb/showthread.php?t=106056

Last edited by Elliott : 02-22-2009 at 07:55 PM.
Reply With Quote
  #5  
Old 02-22-2009, 08:01 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
I have a short bed, I'm only running 33s tires and I would really like to keep it that way. I'm trying to make it as offroad capable as possible with 33s or if needed 35s. I live in the land of huge trucks and I'm really trying to go a slighty different direction with mine. I want to prove that a properly built truck on 33s can do as well offroad as most trucks on 35-38s.


I guess unless someone has some other points about it I'll go for it and see what happens. If I don't like it I can always 4 link it down the road.
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #6  
Old 02-22-2009, 08:53 PM
Elliott's Avatar
Elliott Elliott is offline
Cowboy Up
 
Join Date: Jun 22, 2002
Location: Pilot Point, TX
Posts: 12,704
As soon as you get in their ruts you'll find out it won't... but you can certainly build a more capable rig with your intentions.
__________________
*** I am collecting pics and info on any factory Jeep Dually trucks from the J-Series at the new Jeep Dually Registry.
***I can set you up with hydroboost for your brakes: http://www.ifsja.org/forums/vb/showthread.php?t=106056
Reply With Quote
  #7  
Old 02-22-2009, 09:11 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
Very true about they're ruts Elliot, I won't be able to beat them in straight up mud but in overal trails I think I can oust them with some well planned modifications.
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #8  
Old 02-22-2009, 09:51 PM
Elliott's Avatar
Elliott Elliott is offline
Cowboy Up
 
Join Date: Jun 22, 2002
Location: Pilot Point, TX
Posts: 12,704
Well, I don't think that front springs are going to be the answer though...
Maybe go with a quarter elliptic in the rear? http://www.rocky-road.com/quarterelliptic.html
__________________
*** I am collecting pics and info on any factory Jeep Dually trucks from the J-Series at the new Jeep Dually Registry.
***I can set you up with hydroboost for your brakes: http://www.ifsja.org/forums/vb/showthread.php?t=106056

Last edited by Elliott : 02-22-2009 at 10:11 PM.
Reply With Quote
  #9  
Old 02-22-2009, 10:11 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
Well I'll weld up some new hangers and put them on the frame and try it out before cutting off the extra frame and old hangers. That way if I don't like it I can just switch right back to the longer springs. It will probably happen within the next two weeks so I'll let you guys know how it turns out.


It may just turn out to be the perfect low budget solution to my problem. More then likely though it will be like normal and you will be right and the shorter springs will suck
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #10  
Old 02-22-2009, 10:22 PM
Elliott's Avatar
Elliott Elliott is offline
Cowboy Up
 
Join Date: Jun 22, 2002
Location: Pilot Point, TX
Posts: 12,704
You can have your cake and eat it too...

http://image.jpmagazine.com/f/8466928/154_0804_01_z+1982_jeep_cj7_bigger_better+axle_vie w.jpg
__________________
*** I am collecting pics and info on any factory Jeep Dually trucks from the J-Series at the new Jeep Dually Registry.
***I can set you up with hydroboost for your brakes: http://www.ifsja.org/forums/vb/showthread.php?t=106056
Reply With Quote
  #11  
Old 02-22-2009, 10:48 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
Wow.....I'm not even sure what that is....
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #12  
Old 02-22-2009, 11:27 PM
Gearhead 1990's Avatar
Gearhead 1990 Gearhead 1990 is offline
Grease Monkey
 
Join Date: Dec 18, 2006
Location: Sandpoint, Idaho
Posts: 279
I think it will work just fine. My dad has wrangler springs front and rear on his Zuki which I think are about the same length as stock FSJ fronts and it will still flex about 3 feet..... You might be able to get a little bit more out of stock rears but for what you say you do shorter springs should be just fine. Put lockers in it front and rear and you will be surprised at where you can go
__________________
No jeeps at the moment
Reply With Quote
  #13  
Old 02-22-2009, 11:31 PM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
I've already got a spool in the front and a rebuilt track-loc in the rear (which sucks by the way). It will already go more places then my old stock TJ, I just need to improve the angles some and get better tires.
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #14  
Old 02-23-2009, 12:23 AM
Dmntxn77's Avatar
Dmntxn77 Dmntxn77 is offline
Hey watch this...
 
Join Date: Nov 19, 2004
Location: Gig Harbor, WA
Posts: 8,327
Quote:
Originally Posted by deadironrat
Wow.....I'm not even sure what that is....


Looks like a quarter elliptical to me.... Good off-road, not so good on road...


Regarding your front to rear spring swap.... Personally, I think its a bad idea. Since you want to keep 33" tires, you need to make up for the smaller size with serious flex. You will severely limit flex doing the swap. So, for you, it sounds quite counter productive...
Reply With Quote
  #15  
Old 02-23-2009, 12:29 AM
Dmntxn77's Avatar
Dmntxn77 Dmntxn77 is offline
Hey watch this...
 
Join Date: Nov 19, 2004
Location: Gig Harbor, WA
Posts: 8,327
Just bobb the frame after the springs, then build a tube bumper that you can mount as close to the springs as possible. I think that you will be surprised with the difference that it will make.

In fact, if I were you, and didnt want to go ahead with a 4 link, I would swap to 63" cheby springs instead. You can orient the springs so that there is more spring in front of the pin than behind....
Reply With Quote
  #16  
Old 02-23-2009, 01:15 AM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
Ok so dumb question, why does the rear need to flex so much more then the front? I have plenty of flex out of my front springs and never pick up tires, why wouldn't that much flex be enough in the rear?


I really like the other ideas you guys have suggested and I may end up using one of them down the road when I have more money. As for right now I can throw in the front springs about move the rear hanger for under $50. Of course thats not counting if I'll need to shorten the drive shaft.


The best way to learn is through trial and error, and I've never heard of anyone doing this and it may acutally work pretty well. I know I'll lose some flex, but I'm going to gain alot of depature. I've wheeled it a fair bit and I never even come close to maxing out my springs unless I try, on the other hand I drag the rear bumper all the time.


How many of you guys that are running stock springs pick up front tires on a regular basis?
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #17  
Old 02-23-2009, 01:24 AM
Dmntxn77's Avatar
Dmntxn77 Dmntxn77 is offline
Hey watch this...
 
Join Date: Nov 19, 2004
Location: Gig Harbor, WA
Posts: 8,327
Quote:
Originally Posted by deadironrat
How many of you guys that are running stock springs pick up front tires on a regular basis?

Most wheelers will pick up there front tires pretty much non-stop...

Depending on the terrain of course...

Quote:
Originally Posted by deadironrat
Ok so dumb question, why does the rear need to flex so much more then the front? I have plenty of flex out of my front springs and never pick up tires, why wouldn't that much flex be enough in the rear?

Its not so much that the rear needs to flex MORE than the front. The point is to get as much flex as possible out of both the front and the rear.

The amount of front flex is limited due the the steering. Unless you run full hydro, steering linkage will bind with too much flex.

Now, a reason to get more flex out of the rear is due to the fact that it is the drive axle, and if you want to move, you need the tires to get traction. Since you have a front spool your situation is a bit different.... BUT... More traction is always better and in order to get that traction, your suspension needs to allow your tires to find the terra...
Reply With Quote
  #18  
Old 02-23-2009, 01:30 AM
deadironrat deadironrat is offline
Grease Monkey
 
Join Date: Mar 25, 2008
Location: Quinlan TX
Posts: 382
I agree, the more flex you can get the better, but I have to do something and this sure sounds like a good trade off to me. Like I said I never do any rock crawling and I've never even picked up a tire unless on an RTI ramp. I do mud and trails and approach and departure is very important for dropping off into mud holes, and driving through things like creek beds. If it ends up sucking horrible I'm not out much money anyways.
__________________
Jacob Z

1984 Jeep Grand Wagoneer, work in progress
Reply With Quote
  #19  
Old 02-23-2009, 01:39 AM
Dmntxn77's Avatar
Dmntxn77 Dmntxn77 is offline
Hey watch this...
 
Join Date: Nov 19, 2004
Location: Gig Harbor, WA
Posts: 8,327
Yep, its a near free mod...

If you are set on it, then go for it... I am not trying to be all negative. There is something to be said for trying someting new.

It wouldnt work for me, but that does not mean that it wont be great for you....

Last edited by Dmntxn77 : 02-23-2009 at 02:16 AM.
Reply With Quote
  #20  
Old 02-23-2009, 06:33 AM
4x4fEvEr's Avatar
4x4fEvEr 4x4fEvEr is offline
Master Mechanic
 
Join Date: May 25, 2005
Location: abingdon, va
Posts: 803
Bad idea. You want to move the axle forward cuz you keep dragging the BACK end off? Leave it be. Dove it bob it. Wheel the tires off.
__________________
77 cherokee chief 360/435/205-60/60-42's
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 05:20 PM.


Powered by vBulletin Version 3.5.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
corner corner