This "clocking" of bushings is really interesting. Are you saying that in order to make sure the bushings do not twist at static ride height you need to compress the suspension to static ride height as you tighten the bolts on the bushings?

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Lots of truth here. You get what you pay for. Speaking of suspension, I will use my front end links as an example. I have the enormous Hotchkiss anti-sway bars and after about 2 track days my front end links started clunking loudly. I upgraded to SPL front end links that have given me zero issues in years, but they certainly cost a lot more.

 

Correct. Your suspension has to be set to static ride height before tightening any pivoting bushings. This is how its done when the car is assembled at the factory

If you change your ride height, you need to now re-clock all the bushings that pivot. I recommend a re-clock for anything more than a 0.5" drop - every car's suspension motion is different, however.

Universal rule though....never ever tighten a pivoting rubber bonded bushing when the wheels are drooping (like when a car is on jackstands). You'll do a ton of damage to the bushing when you set the car down on the ground.

Some cars have bushings that have to be pressed into a properly clocked position. Think rear trailing arm bushes on 90's Honda's.
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Ha! SPL was one of the examples I was going to mention regarding a part that's truly created to a more durable spec than OEM. Maybe not in the long-term, all weather use department since the joints are not booted. But if you want an endlink that's truly stronger than OEM...the SPL is your choice.

In comparison, I doubt an "OE replacement" link would last 10K miles even with a stock sway bar.

 

Yes. Upon installing an ARM and tightening you lock the inner metal barrel with the chassis leaving the rubber of the bushing to do the work. I dont know of any manufacturer that clocks bushings from factory, this could be because the stock height does not need it or that it would be extremely difficult for a workers in the assembly line to preload bushings prior to. So in the air and only then will be the only time the bushings will be at rest. Even on static height the bushings provide feedback.
So if an aftermarket company develops springs that were tested in a car that without clocked bushings then the results should be tested on non clocked bushings.

The issue I see here is if you clock them to extend their lives you'll remove some rebound in the spring/shock though it might sound like minimal, when all four corners are trying to get back to resting form it should help. It would have been interesting to document the any changes in ride/comfort with and without clocked bushings however I doubt we will see that from you.

 

Hugh, you will now and forever be known asicon17:

 

Bushings are all 100% for sure clocked to stock ride height from the factory. Its done on jigs or via measurement during the individual assembly phases.

Some Acuras even come with holes in the unibody to put a straight rod through as a guide, in order to clock control arms during assembly.

An example of this proof on a G37 would be if you've ever had a car on jackstands and disconnected the front UCA ball joint and watched the UCA spring upward. I'm sure some of you can relate.

But yes...bonded bushings add to effective spring rate.

Even unbonded poly bushings add rate via friction.

Only cars with spherical bearings will enjoy a "zero bind" condition.

 

This is really interesting. I have been to a lot of different car factories and watched assembly, but I cannot think of any instance where suspension parts were installed with the car at ride height or where the suspension was compressed to compensate. I wonder if there are a lot of companies that do not do this or, more likely, I never knew it was a thing and noticed.

This got me thinking about repair shops. I wondered if most were familiar with this. I just asked a bunch of my more experienced technicians and only 2 were even familiar with it. One said he always tried to use a drive on lift so everything was compressed when he loosened and then re-torqued the control arms. The other technician showed me few points on an Altima up on a lift (much easier than what you described on our cars) and said that it was recommended, but he thought the small degree change was usually not enough to do much damage because the suspension was in constant movement anyway.

 

Factory parts are sometimes bought as assemblies. Entire front subframes, for example, can come from a "supplier".

But yes...they're using jigs or some sort of angle setting to make sure they are clocked.

As far as technicians go...maybe they haven't been taught to do this. But check out any FSM for any car. See what it says about installing a new control arm, for example.

 

Fascinating. I'm sure you're right. It just scares me when you think about how many shops put on aftermarket parts and I would be willing to bet that 80-90% of these technicians either have no idea about this or just don't do it.

 

Its a time consuming process to do things like this. Most techs don't feel they're presented with enough time to do this kinda stuff.

NO OFFENSE to anyone who is a tech. But... this is similar to how lots of bolts that should be torqued just get some rough amount of ugga duggas...

 

That is very true and also the reason I usually turn all the wrenches on my own car. I think I only had one of my techs work on my car for the headers because I knew it was a time consuming PITA and the front upper control arms because I have not had anyone show me how to use our fancy new alignment machine yet.

The headers were worth it, but I almost immediately regretted having someone else install the front upper control arms. He put one in upside down and wondered why the alignment was off. (I'll give him some credit on this because they do look very similar if you have not installed them before) But then they started making a lot of noise. It turns out that he did not torque any of the bolts attaching the FUCA's to the body and they came loose on the driver's side?? Worse yet, I got more noise from the sway bar because he left the driver's side end link completely loose. And this was from a Master Certified Nissan technician. Yikes!