Polyurethane Bushings, Can I tighten them now or wait until it's on the ground?

[WH23G3G]

On my 73, Can I tighten all the control arm nuts, strut rod nuts, and sway bar nuts before I drop it since I'm using polyurethane bushings? The factory chassis manual says to weight until the car is on the ground with the full load of the vehicle on it's tires. I still have to put the motor and trans in anyway. I thought I read in one of the Mopar Muscle tech articles where it was said it's ok to tighten the bolts up if you're using poly urethane because they're so stiff. I'm afraid after I finally get the motor,trans, fuel tank, lines, and everything else done and do I final check I might not remember to check the suspension bolts eventhough I will go through everything I can think of before I get it on the road.

[TylerCharger69]

I may be wrong,  but I don't see any reason why you can't go ahead and tighten them up...If I am wrong somebody tell me so...and for what reason

[Plumcrazy]

I would wait until the front end is sitting at it's normal ride height with rubber or poly bushings.
If you tighten it now the inner sleeve will be clamped in place.  When you get the front ends ride height set there will be a twisting force on the bushing that can shorten its life.
If you wait until you set the ride height before tightening things down you will eliminate the twist on the bushings when the car is just sitting there.

[firefighter3931]

I would wait until the front end is sitting at it's normal ride height with rubber or poly bushings.
If you tighten it now the inner sleeve will be clamped in place.  When you get the front ends ride height set there will be a twisting force on the bushing that can shorten its life.
If you wait until you set the ride height before tightening things down you will eliminate the twist on the bushings when the car is just sitting there.

 
Load the suspension first then tighten evrything down.



Ron

[chgr500]

Always tighten bushings in the loaded position.  Suspension won't settle properly if tightened in a hanging position.  You could use a floor jack on the suspension to load the bushings if it were on jack stands.

[Charger-Bodie]

  wait til its got the load on it !

[WH23G3G]

Is this true with just the Control arm nuts, or is it true for the K-member bushings, sway bar nuts, and strut rod nuts too?  I tightened them up to factory 50ft-lbs, I didn't want wait until I put the motor and trans back in and everything else and drop the car and have the whole K-member suspension and all break. Is that going to mess it all up now? The K-member bushings are Poly too and they got pretty tight when I torqued them down to 50ftlbs. It doesn't seem like it would work if you just had them in finger tight and with the addition of motor/trans and suspension components, it could break when you try to tighten it all up with all that load on there. But I think the chassis manual is assuming you've got the motor off the mounts supported by an engine hoist, so that's basically to the point where I am, right?

[firefighter3931]

No problem tightening the K-member bushings to spec before loading the suspension because there is no twisting motion on those. The rest i would tighten to spec after the drivetrain was installed with the suspension loaded. 


Ron