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Discussion Starter #21
Basically yes. as long as the suspension is at ride level and those forces on the suspension are in place. If you can put the rear wheels on to do this I would. You could also loosen the rear front control arm at this time and re-set that as well. No other bushing on front needs to be set in this manner.

I will tell you, once I made this mistake. I installed new bushings on a car, did not set it at ride level but instead up in the air. Car sat 1" higher and wore the bushings within a few months. This was when I was much younger and ignorant to this.
Learned my lesson.
I've never had a car that needed this, there was always play even when torquing down bushings. The resistance came from the shock/spring only.

Also while I'm down there I need to torque the ball joint nuts as well, those should be set fully loaded.
 

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Mostly European cars I have had to torque bushings down in this manner.
 

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To add to my post above (sequence... did I get the sequence right?) then in theory I could also drop the car on to 4 jack stands mounted under the hubs which would then basically have the weight of the car on the points it should be, while still giving me room to work.and then torque all bolts.
Where exactly would you locate these stands under the hubs in a way not to endanger your safety? The front jacking points could surely be use at least. Would something like positioning the car with a brick under each wheel suffice to give enough clearance to access the bolts? Or mostly tighten the bolts then drive cautiously to a garage with four-post ramps to lift it and safely do it properly?

Don't forget about the positioning of the brake balancer arms - if the adjuster nuts (M5?) have been undone the position will need to be correctly reset; though don't ask me how.

Good luck with it all.
 

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Discussion Starter #24
Where exactly would you locate these stands under the hubs in a way not to endanger your safety? The front jacking points could surely be use at least. Would something like positioning the car with a brick under each wheel suffice to give enough clearance to access the bolts? Or mostly tighten the bolts then drive cautiously to a garage with four-post ramps to lift it and safely do it properly?

Don't forget about the positioning of the brake balancer arms - if the adjuster nuts (M5?) have been undone the position will need to be correctly reset; though don't ask me how.

Good luck with it all.
So currently the car is on a set of Quickjacks

https://www.quickjack.com/

The car is about 2 feet in the air right now. I can easily place 4 jackstands at their highest safe points under each hub (under both rear strut bodies, and under the balljoints up front) and then lower the car down on to them just enough to load up the suspension and clear the bottom of the car. So they will still be there in a worst case scenario, just without load on them.

My backup is my friend works at the shop that does my inspections/alignments so I could drive it there (about a mjle) but i would have to pay them to torque the bolts. Thats a worst case though, I actually have Longacre toe plates, Camber and caster gauge and so on so I would rather be doing the alignment myself and just do the inspection there when done.
 

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If the spacers fit over the ends of the inner steel sleeve of the bushing there is no need to load the suspension before torquing up the bolts. The diagram indicates this is how the spacers fit. Do they? Looking at the thread I linked you to it certainly looks that way. If that's not the purpose of these spacers it's hard to see why they are there at all.
 

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Michael, what I don't think you're taking into account is the fact that this is not a model car sitting on your desk. It's a 3000lb vehicle designed for speeds well in excess of 100 MPH. A metal sleeve sliding over a bolt with no lubrication beyond initial greasing is not a feasible bearing design for (at least) three reasons:

1) Going down the road at highway speeds the suspension is in constant motion. The friction would quickly overheat the surfaces.

2) When a bump is hit at these speeds there is a tremendous twisting force on the suspension members due to the force vectors involved - hitting a bump produces both an upward force on the wheel as well a backward force. This would cause the sleeve to bind on the bolt unpredictably.

3) Even if the first two were not true, a sleeve sliding on a bolt would wear out extremely quickly.

Therefore the metal sleeves of a rubber bushing MUST be held rigid on both the inner and outer sleeves. The rubber provides the range of motion necessary. This is a pretty universal suspension bushing design and it's well understood in an engineering sense. The rubber thickness and durometer are carefully chosen to accommodate the designed range of motion.
 

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Therefore the metal sleeves of a rubber bushing MUST be held rigid on both the inner and outer sleeves. The rubber provides the range of motion necessary. This is a pretty universal suspension bushing design and it's well understood in an engineering sense. The rubber thickness and durometer are carefully chosen to accommodate the designed range of motion.
Exactly! Exact reason why you cannot torque them down up in the air, they will be set or rigid in their positions. Place the car on the ground at ride level and you have twisting to the rubber occurring without anything happening, just sitting at ride level. This causes many issues from quickly wearing out the bushing by maxing it out when it encounters any motion, sometimes ride height change, alignment issues, handling issues and so on.
 

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My initial view resulted from the absence in the ARDONA shop manual of any reference to torquing the suspension bolts only after compressing the suspension to normal ride height. Perhaps this is because ARDONA presumes all mechanics would know to do this.

I have no vested interest in being right or wrong, only in understanding the suspension design and the repair process.
 

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I have no vested interest in being right or wrong, only in understanding the suspension design and the repair process.
The rubber bushing is an extremely interesting piece of technology. It's a really simple piece of kit, but it brilliantly solves a complicated engineering problem: how to design a joint that maintains geometry while allowing for twisting and flex (no matter how rigid a suspension part, there is always SOME flex) AND dampening noise and vibrations while being reliable, low maintenance and economical to manufacture.

The rubber bushing is also somewhat counterintuitive as you pointed out because it does not really allow free movement - but it allows free enough movement within a very small range of motion. But a surprisingly small range of motion is all you need. When you tighten the bolts with the suspension weighted, what you're actually doing is setting the center of this small range of motion.

According to this article on Monroe's website it was invented by Walter Chrysler himself in the '30s...

https://monroeengineering.com/blog/the-beginners-guide-to-bushings/
 

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Just an idea.

Could not the inner arm ends, against the subframe, be held at the correct angle and tightened before the outer bolts are fitted, and then, with the car slightly raised from the ground just enough to fit the outer bolts, the car could then be lowered to the ground and outer bolts tightened on the deck, in the correct position/loading?

As for getting the right arm angles at the subframe end, they could be measured/photgraphed before dismantling.

Any thoughts?
 

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Discussion Starter #34
Just an idea.

Could not the inner arm ends, against the subframe, be held at the correct angle and tightened before the outer bolts are fitted, and then, with the car slightly raised from the ground just enough to fit the outer bolts, the car could then be lowered to the ground and outer bolts tightened on the deck, in the correct position/loading?

As for getting the right arm angles at the subframe end, they could be measured/photgraphed before dismantling.

Any thoughts?
In theory sure, but that sounds a bit too much like a guesstimate that may be somewhat off. Also if the old bushings are trashed your measurements won't be good.
 

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In theory sure, but that sounds a bit too much like a guesstimate that may be somewhat off. Also if the old bushings are trashed your measurements won't be good.
Surely if trashed old bushing or not, won't the angles recorded on the car on the ground still be accurate? And even if measured off the ground, after subframe removal via the outer bushes, won't even trashed inner bushes not under load revert to their correct positions? There is no 100% fixed angle here - the bushes by their very nature have a degree of play so as long as they are tightened at least close to the ideal should it not all be fine?
 

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Discussion Starter #36
Surely if trashed old bushing or not, won't the angles recorded on the car on the ground still be accurate? And even if measured off the ground, after subframe removal via the outer bushes, won't even trashed inner bushes not under load revert to their correct positions? There is no 100% fixed angle here - the bushes by their very nature have a degree of play so as long as they are tightened at least close to the ideal should it not all be fine?
In theory yes, but IMO a margin of error exists and if theres a way to avoid that which could significantly affect longetivity thats the best route. In mean in theory you could get 4 wood planks as well, drive the car up on them that will give you a few inches to work with to wiggle under there and torque them down.

Or do it your way and then when you bring the car to be aligned have the shop loosen and re-torque.
 

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I've not used a spring compressor but it seems to me that this would work. If you can measure the spring length at normal ride height just use a spring compressor to achieve that length and bolt the suspension up and torque it.
 

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Discussion Starter #39
I've not used a spring compressor but it seems to me that this would work. If you can measure the spring length at normal ride height just use a spring compressor to achieve that length and bolt the suspension up and torque it.
As someone who has used a spring compressor this is a terrible idea.

First off once you compress the spring you would still need to jack up the corner you're working on to the spring as the damper doesn't compress with a spring. Secondly external spring compressors which is what you'd need to use are ultra dangerous and can result in serious gruesome injuries should it slip off. I say this because I have actually seen this happen more than once. There are some better ones out there these days but its not a quick simple tool to use inside the strut tower.

This is a problem that can be solved by driving the car up on 4 double wood planks, or hitting a local shop, or 4 jack stands under the hubs, all of which are faster and significantly safer.
 

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Rougue Leader, you are right. I totally missed the element that the damper will remain fully extended. Glad you pointed it out before I tried it and had one of those 'Duh' realisations. Would be confident the compressors wouldn't slip off as they would hook around the curved bottom of the strut and the spring coils but the exercise itself would be totally pointless, as you have correctly pointed out - unless something like a bottle jack was used to squash the damper too - wouldn't lift the car with the spring compressed.

Personally not too keen on the plank idea stability wise so have got round it here by buying a pair of wide car ramps to safely raise the rear wheels enough to gain bolt access, while the front can be raised with a trolly jack and axle stands. Problem solved, at last.
 
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