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DGG
10-15-2012, 09:17 AM
I installed the springs this weekend on my 109 station wagon rebuild. What do I do to finish the installation, just torque the bolts down? What is the torque, is it 70ftlbs? The workshop manual says to compress the springs, then tighten the bolts, is this true for the parabolics?

Thanks,
Doug

I Leak Oil
10-15-2012, 10:52 AM
I leave the shackle bolts slightly loose, drive around for a couple miles, then torque them to 70 ft-lbs. while the truck is sitting at ride height on a level surface. Works well for me.

I've read that preloading the bushings in the manual too....I don't quite understand why.

jonnyc
10-15-2012, 11:08 AM
I left everything loose-ish for about a week, and aimed for potholes, speedbumps, and manhole covers. Settled the springs down nicely and tightened everything up to spec.

DGG
10-15-2012, 11:39 AM
Thank you.

ArlowCT
10-15-2012, 06:51 PM
It depends what type of spring bushing you are using. If staying stock (rubber with built in shelve), yes drive around some before you torque them to spec. If using poly bush there is no need to "settle" the suspension. The shelve for the poly bush is free to rotate and should not preload the springs in any way. This causes a softer ride but they do not last as long. IMHO I would rather have the nice ride and replace often, the poly is just too easy to swap out!