Final suspension bolt tightening

I had the front suspension and K member completely out of the 68 Barracuda.
I think that I remember reading that some bolts need to be tightened after the vehicle is set down on the ground. Is that correct and if so, which ones? Also should the ride height be set prior to the tightening?
And what about the rear, anything special there, as I also had the rear leafs off.
Thanks

my68barracuda said:

I had the front suspension and K member completely out of the 68 Barracuda.
I think that I remember reading that some bolts need to be tightened after the vehicle is set down on the ground. Is that correct and if so, which ones? Also should the ride height be set prior to the tightening?
And what about the rear, anything special there, as I also had the rear leafs off.
Thanks

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Anything that "moves" with the suspension. Control arms, shocks, leaf springs if you had those loose. If it pivots or moves with the suspension is jounced, it should be left loose until weight is on the suspension.

Also, if you had the shock plates loose, those should be tightened finally with the weight on the suspension. 45 LB FT

Actually a lot of that is overkill. The only thing that really has to be torqued on the ground with the ride height set is the lower control arm pivot nuts, and only if you’re using OE style rubber bushings. The pivots don’t move (torqued to like 90 ft lbs) so the entire up/down movement of the LCA is dependent on the give in the rubber bush. The bushing doesn’t spin in the shells or on the pivot, and it will tear of its not tightened at ride height or in the middle of the range of travel. Tightened at full extension it won't have enough give to go to full compression without tearing that bushing.

All of those other pivot points have bushings that spin on a bolt. The UCA bushings rotate around the UCA eccentric bolt, they don’t depend on the flex in the rubber to rotate. Upper shock mount is just sandwiched, the lower rotates on the bolt. The leaf spring shackles would benefit from being tightened with weight on them, but tightening them in the air won’t usually cause catastrophic failure of the bushings if they were just installed. If they’re old and stuck to the shackle bolts they might fail, but if they’re that stuck they’d probably fail when they were disassembled before they failed on re-tightening.

And if you use poly or Delrin LCA bushings you can even tighten the LCA pivots nuts in the air, the poly and Delrin bushings spin on the pivots.

tearing up the (rubber) bushings prematurely is a real possibility if the bushing is not tightened in its neutral (car at rest on tires on a level surface) position. But before that happens, you will probably be very disappointed in how poor the car will ride. It will have little compliance, riding very harshly.

Thanks guys!

If the LCA pin is installed at full droop and snugged up, it may still tear the bushing when torqued at ride height. You have to make sure the pin rotates to the neutral rested position of the bushing before it's fully tightened. I've made that mistake once. For some reason, the bores the pin goes into were grabbing the pin and not allowing it to rotate back when the suspension was loaded from full droop.

That is a good tip, I will watch for that, thanks