rear fj60 springs on fj40

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i am trying to extend my wheelbase by using fj60 rear springs on the rear of my 40. i have a soa right now and i was wondering if someone ever did that with their 40 . i know the 55 springs will work great but its hard to find them around for good price. i fliped my 40 spring around to get little longer wheelbase but would like to have some more articulation in the rear for cheap.
 
i am trying to extend my wheelbase by using fj60 rear springs on the rear of my 40. i have a soa right now and i was wondering if someone ever did that with their 40 . i know the 55 springs will work great but its hard to find them around for good price. i fliped my 40 spring around to get little longer wheelbase but would like to have some more articulation in the rear for cheap.

I did it and it works well. Extends the WB about 4 inches. You need to be careful about bushings and spring pins to get everything to work, and you will need to remount the rear shackle hanger, and drill the upper crossmember to make new upper shock mounts.

Starting on post #15 in my ROTW thread are some pics and details

https://forum.ih8mud.com/40-55-series-tech/165549-rotw-cruiserdrew.html
 
thanks. did u have to take or add any leaves to the pack to obtain same height as the front 40 spring? are the 60 springs stiffer than 55 springs?
 
thanks. did u have to take or add any leaves to the pack to obtain same height as the front 40 spring? are the 60 springs stiffer than 55 springs?

I added 1 leaf to the pack to make it stiffer. I like my springs really, really stiff as I tend to carry a lot of gear with me.
 
Hi All:

The 60/62/70 Series rear springs are a great upgrade to the rear suspension on a 40 Series; I seen 'em used both SUA and SOA.

Try the "advanced search" function here on MUD and you will find some good info on this swap.

Regards,

Alan



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i am trying to extend my wheelbase by using fj60 rear springs on the rear of my 40. i have a soa right now and i was wondering if someone ever did that with their 40 . i know the 55 springs will work great but its hard to find them around for good price. i fliped my 40 spring around to get little longer wheelbase but would like to have some more articulation in the rear for cheap.
 
Hello, I did that swap, works great(I'm SUA) 2 1/2" lift springs 60 series. Check my build below, used the stock shackle hangers, like cruiserdrew said, you need to research bushing sizes and pins. You'll like it, nice ride, better articulation.:cheers:
 
Here is CruiserDrew's suggestion, found in this thread:

[FONT=&quot]https://forum.ih8mud.com/40-55-series-tech/160124-60-series-springs-42-a.html [/FONT]

[FONT=&quot]"For the rest-if you want to run FJ60 springs in the FJ40 original spring hangers (the fixed end at the frame) you need SOR bushing 289-40-X. It has the proper outer diameter of 1 3/8 inch, a narrow flange and a 15mm hole. Then you use OME [/FONT][FONT=&quot]pins[/FONT][FONT=&quot] which are 15mm. This is the only combination I could come up with that would work. Otherwise you have to replace the hanger with a wider one.[/FONT]"
 
yup, great mod.


the part i like best is the larger bushing diameter and wall thickness which leads to better spring movement and longer bushing life.

the bushings can be bought at sor, i usually use gravelmakers' 6" shackles on the rear which will give you roughly a 45 deg shackle angle. that in turn makes for a nice ride and great articulation.
 
what kind of lift are we looking at with these springs in the rear? i know the wheelbase may increase 4", but what about heighth? thanks
 
Hi All:

Depends upon which 60/62 Series rear spring you use.

For a SOA a pair of stock FJ60/62 rear springs would be best. For SUA I used OME medium-load 60 Series rear springs, which are rated for 3 inches of lift.

Regards,

Alan
 
Here is CruiserDrew's suggestion, found in this thread:

[FONT=&quot]https://forum.ih8mud.com/40-55-series-tech/160124-60-series-springs-42-a.html [/FONT]

[FONT=&quot]"For the rest-if you want to run FJ60 springs in the FJ40 original spring hangers (the fixed end at the frame) you need SOR bushing 289-40-X. It has the proper outer diameter of 1 3/8 inch, a narrow flange and a 15mm hole. Then you use OME [/FONT][FONT=&quot]pins[/FONT][FONT=&quot] which are 15mm. This is the only combination I could come up with that would work. Otherwise you have to replace the hanger with a wider one.[/FONT]"

From what I could tell... OEM spring pins are 15MM as well?
 
Correct you are !!:cheers:
 

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