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Some guys have had problems with these coming loose. They've added jamb nuts, heim ends, used locktite and all kinds of things to keep that from happening. What I found was that as the suspension travels up and down, it doesn't do that in a straight line, it's a bit of an arc. As such, this causes the strut rods to twist as the suspension travels. That's what loosens the jamb nuts. To prevent this, don't over tighten the through bolts that go through the bushings. Those are self locking nuts and only need to be tight enough to eliminate any back and forth slop between the bushing and the mounts. The strut should be able to move up and down with the suspension. After talking with the guys at Van Steel, this is how I installed mine and they haven't loosened themselves once in years.
Some guys have had problems with these coming loose. They've added jamb nuts, heim ends, used locktite and all kinds of things to keep that from happening. What I found was that as the suspension travels up and down, it doesn't do that in a straight line, it's a bit of an arc. As such, this causes the strut rods to twist as the suspension travels. That's what loosens the jamb nuts. To prevent this, don't over tighten the through bolts that go through the bushings. Those are self locking nuts and only need to be tight enough to eliminate any back and forth slop between the bushing and the mounts. The strut should be able to move up and down with the suspension. After talking with the guys at Van Steel, this is how I installed mine and they haven't loosened themselves once in years.
And this binding is my primary concern with the poly equipped struts- either the OEM type or the adjustable ones. If the through bolts are being left loose enough to avoid the jamb nuts being forced loose through torsion, something's wrong. The play being introduced means there's the same or more slop in the suspension than the rubber bushings that were removed.
Mike, loose isn't really accurate I guess. Just not so tight that they bind, so the struts can move up and down is all, but tight enough so there's no slop in them. The poly bushings should reduce any deflection you'd get from rubber bushings (honestly, if that's the only change you made in the suspension, I can't believe you'd notice any difference at all). If you can't get that movement (and I suppose rubber bushings allow enough movement because the rubber gives compared to the poly), the rods will twist. Not much at all, but enough for the adjustment nuts to come loose.
There's several suspension points on C2/C3s where 3D movement is designed into the joint and all effort must be made to not restrict this. The strut rods and trailing arm bushings are perhaps the most important. The basic flaw in using poly in these joints is that it allows movement in only one plane and by design is rigid in all others . You've gotten around the second plane of movement (torsion) by loosening the through bolts, but this does not address the need to also allow the strut rods to move fore/aft as the suspension moves away from the static neutral position. The strut rod does NOT remain perpendicular to the through bolt as the suspension moves.
The best solution is to use a Heim joint, but the OEM rubber bushing is more than adequate in controlling movement for anything other than full race situations.
Mike, loose isn't really accurate I guess. Just not so tight that they bind, so the struts can move up and down is all, but tight enough so there's no slop in them. The poly bushings should reduce any deflection you'd get from rubber bushings (honestly, if that's the only change you made in the suspension, I can't believe you'd notice any difference at all). If you can't get that movement (and I suppose rubber bushings allow enough movement because the rubber gives compared to the poly), the rods will twist. Not much at all, but enough for the adjustment nuts to come loose.
My turn for more coffee now...
Thanks for the great tips. I will make sure I follow the advice. Cheers.
decided you didnt deserve , sides you went and got coffee and started posting good tech. how was the beer?
I dont mind being told I'm wrong, just want to learn from it.
I used poly bushings in the OEM strut rods for years and they never loosened but squeaked too much for my liking. Changed to competition adjustable with heim joint struts a few years ago and they have been great for ride, handling, and no noise. The rods don't flex under load, they keep the camber perfect, they eliminate unwanted camber change under load, and have made the rear end feel attached to the rest of the car! I would never go back to a strut with rubber or poly bushings.They are a great investment at about $200 for the pair-money well spent.
For BrianPA- you went to extra work for nothing by swapping the hardware, but it did no harm. The adjustable strut rods are similar to a turnbuckle. The ends must stay still while the centre section is rotated to lengthen or shorten the total length. That's why there's a left and right thread on each unit.
It took only a few seconds to swap the hardware for the Left/Right thing, the killer was when I realized I didn't balance the threading exposure and had to re-install one end of each strut to fix!
Glad to know that C3 struts should the same size on each end. I really didn't want to have to do that again.