63" chevy's on a fj60?

[GRM]

I have a very heavy 4runner and did this 63" Chevy spring swap. Here are my experiences

3 leaf packs were way too soft. The springs didn’t not have the ability to control the sway of the truck, and made my 4runner dangerous to drive on the highway.

My 4 leaf packs were great... with the top off. When I bolted the top on it had the same issue as the 3 leaf packs.

Now I have 4 leaf packs with a rancho add a leaf. It works great, rides soft, decent travel (I use 12" travel shocks, and don’t see the need to have more travel than that), and cost effective.

I found that if the springs are under 250-275 in lbs they are too soft for a heavy wagon. With my poor calculations a 3-leaf pack are 175 in lbs.

Also note, the more of a shackle angle, the more the shackle has leverage over the spring, thus making it effectively softer. My shackles are at 45° which may explain some of the springs soft tendencies. If I had mounted the shackles closer to 90° it would give me an effectively higher spring rate with better handling characteristics (but a harsher ride).

Take it as you will. My Chevy springs work well for my application, and plan to continue to run them for years to come.

[5280Hawk]

So what would it be like to put the 63" chevy springs on a SUA 60?

Would it help w. flex?

Could i Use the stock U bolts, AI shackles? Ect?

Do you move the Front spring perch or the back or both?


Looks like a great way to get more articulation.

[boots4]

Originally Posted by 5280Hawk

So what would it be like to put the 63" chevy springs on a SUA 60?

Would it help w. flex?

Could i Use the stock U bolts, AI shackles? Ect?

Do you move the Front spring perch or the back or both?


Looks like a great way to get more articulation.

That's what FL cruiser did in post #28 although he is using lift springs and SOA guys are using stock heigth springs. At least for SOA I had to move both spring hangers (plus I put the shackle through the frame to reduce lift heigth). On my previous rig that I put 63" on it flexed great!

[5280Hawk]

I have Heavies on it right now, it's already lifted about 3.5" above stock Ht. do you think i would lose lift??

It seems like if you move the front spring perch far enough you could still use the back one as-is. and can't you modify the top spring leaf so the the centering pin still lines up with the axle?

What if you reversed the shackles and the moved the shackle perch all the way in to mount the chevies?

[boots4]

Originally Posted by 5280Hawk

I have Heavies on it right now, it's already lifted about 3.5" above stock Ht. do you think i would lose lift??

It seems like if you move the front spring perch far enough you could still use the back one as-is. and can't you modify the top spring leaf so the the centering pin still lines up with the axle?

What if you reversed the shackles and the moved the shackle perch all the way in to mount the chevies?

Easiest would be to buy/make new spring hangers. The front hanger has that funky bolt that is 19mm. The holes in the chevy bushings are 9/16" so that bolt is too big to reuse, which means that the spring hanger would have to be modified and you might as well buy new hangers. You could re-use the rear shackle hanger but not the shackles for the same reason of the larger, fixed bolts on the shackle (new shackles would be easy to make).

The centering pin goes though all the leaves in a pack so to move that pin you would need to drill a new hole through all the leaves to the spot you want to position the axle on that spring pack. However I'm not crazy about drilling another hole in a spring pack.

I'm not understanding the last question yet.

[FL cruiser]

Originally Posted by 5280Hawk View Post
I have Heavies on it right now, it's already lifted about 3.5" above stock Ht. do you think i would lose lift??

It seems like if you move the front spring perch far enough you could still use the back one as-is. and can't you modify the top spring leaf so the the centering pin still lines up with the axle?

What if you reversed the shackles and the moved the shackle perch all the way in to mount the chevies?

My 60 previously had 3.5" lift and I had to go with Chevy lift springs to maintain height. You would loose lift if you used stock Chevy springs unless you went SOA. Procomp and Superlift make Chevy 3.5" lift springs. The Chevies are so much longer you just gotta move out hangers at both ends and/or make new hangers.
Like Boots 4 said, none of the bolts bushing or hardware can be used. Might as well make new hangers. The springs I bought came with bushings that had a 1/2" hole. I made front hangers out of 3.5" square tube which happens to be 3" ID. The chevy springs are narrower. They would flop around inside the Toyota spring pack holder, so made some craddles to go around the springs and fill up the slack. Also made up some steel centering dowels because the Toyota rubber pads with centering pins wouldn't fit in the craddles. Rear hangers made out of thick wall 2" sq tube and 1.5" ID tube.

[5280Hawk]

I'm not understanding the last question yet.

Probably because you do not do a shackle reversal on the back.

sorry -

Spring perches would definately be easy enough to fab.

[Wayneraintree]

I ordered the sky-manufacturing kit and it was a good value:

http://www.sky-manufacturing.com/

Look under Toyota/minitruck/suspension..

The 3/4 ton in SOA config. worked great under the pig... 2WD are three leaves and helper and the 4WD are 4 springs and helper IIRC.. I used the 2WD version with the helper.