"Bushing bind?" Leaf spring bolts/shackles: how tight?

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MRGTX

MRGTX

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When swapping leaf springs out, I gather that it's standard practice to snug up all of the bolts (but not torque them down), put weight on the suspension with the car on the ground, bounce it a few times, then tighten up the bolts on the mounts and the shackles.

This is basically the procedure that I followed when swapping out my stock leaf springs for the heavy duty Hotchkiss lowering springs/1.5 shocks and I assumed everything was good. Yeah, the rear suspension was really stiff but I assumed that's how these new springs were supposed to be.

Last week, I noticed that my car was sitting a tiny bit higher on the driver's side and I decided to try to try again...after loosening up all of the bolts a bit, I noticed that the suspension, while still pretty stiff, was suddenly quite a bit more compliant and I could move the car quite a bit more when pushing down on the bumper...and it got me wondering if maybe this is how the were supposed to be and perhaps I had been in bushing bind all along.

So...what's your procedure? Should the bolts and shackles be torqued tightly?
 
MRGTX said:
When swapping leaf springs out, I gather that it's standard practice to snug up all of the bolts (but not torque them down), put weight on the suspension with the car on the ground, bounce it a few times, then tighten up the bolts on the mounts and the shackles.

This is basically the procedure that I followed when swapping out my stock leaf springs for the heavy duty Hotchkiss lowering springs/1.5 shocks and I assumed everything was good. Yeah, the rear suspension was really stiff but I assumed that's how these new springs were supposed to be.

Last week, I noticed that my car was sitting a tiny bit higher on the driver's side and I decided to try to try again...after loosening up all of the bolts a bit, I noticed that the suspension, while still pretty stiff, was suddenly quite a bit more compliant and I could move the car quite a bit more when pushing down on the bumper...and it got me wondering if maybe this is how the were supposed to be and perhaps I had been in bushing bind all along.

So...what's your procedure? Should the bolts and shackles be torqued tightly?
Click to expand...

There is a torque spec for the shackle bolts. I thought it was 35 ft lbs, but that's off the top of my head. My shackle bolt nuts are the crimped style so they don't back off when used with such a low torque.

Also, I always use synthetic disc brake grease from CRC on all my rubber and poly suspension parts including the spring eye, swaybar & shock bushings. It dramatically reduces suspension sticktion and prevents squeaks. It helps make my suspension a lot more compliant on the road too.

Be aware that there are some new types of synthetic disc brake grease out there now, but they don't have Moly, PTFE and graphite in them. They are just the synthetic grease.
 
Do not "snug" the bolts/nuts first with weight off suspension. Just get the nuts close so you don't have to ratchet them too far with torque wrench. I usually "snug" them, and then back off a couple turns until loose, then put car on ground, jounce it a few times, then torque.
 
Thanks, guys.
Yeah, I’ve definitely been driving around at way over 35ft/lbs of torque.

Good call on the grease. I used the lithium goop that came with one of the suspension components but I could probably benefit from another application.

The bolts on the spring perches toward the front of the car...anyone have a torque spec there?

Thanks!!!
 
MRGTX said:
Thanks, guys.
Yeah, I’ve definitely been driving around at way over 35ft/lbs of torque.

Good call on the grease. I used the lithium goop that came with one of the suspension components but I could probably benefit from another application.

The bolts on the spring perches toward the front of the car...anyone have a torque spec there?

Thanks!!!
Click to expand...
My factory manual say 30 foot pounds for valiant/ all others 40 foot pounds for shackle nuts.rear hanger bolt 30 foot pounds.

15789721204464222980267061335370.jpg
 
The rear shackle nuts can only tighten down until they bottom out. So over tightening won't damage the bushings, but of course it will stretch the studs and ruin the nuts, so the 30 LB FT is right. And you are also correct in that you make your final torque with the weight of the car on the suspension. You CAN do that with the rear axle housing on jack stands. I know it sure helps "my old butt". lol
 
jbc426 said:
There is a torque spec for the shackle bolts. I thought it was 35 ft lbs, but that's off the top of my head. My shackle bolt nuts are the crimped style so they don't back off when used with such a low torque.

Also, I always use synthetic disc brake grease from CRC on all my rubber and poly suspension parts including the spring eye, swaybar & shock bushings. It dramatically reduces suspension sticktion and prevents squeaks. It helps make my suspension a lot more compliant on the road too.

Be aware that there are some new types of synthetic disc brake grease out there now, but they don't have Moly, PTFE and graphite in them. They are just the synthetic grease.
Click to expand...

Red rubber grease can also be used. The important thing to remember is some greases eat rubber.
 
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