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Unread 11-16-2016, 05:23 PM
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Default Strut and Shock Mount TOP NUT TIGHTENING

The tech tip video below is important and we wished more people would abide by the advice it gives.



The only safe way to make sure the strut top nut gets tight is to use an impact wrench, either pneumatic or electric. There is not a safe, effective way to "hold" the strut shaft while you tighten the top nut with hand tools. You can almost get it tight enough... but the shaft wants to spin to counteract the torque of the top nut.


This is one of those times you NEED to use air tools to get the job done right

To properly tighten these Nylon-locking strut top nuts properly you have to "impulse" the nut with the impact gun. You will never get it truly tight with hand tools. A typical M14-1.5 nylock top nut needs 71 N-m (52 ft-lbs) of torque. That's nearly impossible to tighten with a proper torque wrench (mostly because there's no way to hold the top of the shaft at the "flats" or "hex") so we always use an impact, pulse the nut down, and then watch and listen. Watch for the nut to stop moving down the shaft - the same number of threads are visible. Listen to when the sound of the impact gun changes pitch, then you know you've bottomed the parts on the shaft and it is tight.

Removal is the opposite of installation: pulse the impact gun and it should come off after a few tries. If the strut shaft or nut are showing signs of corrosion, pre-spray the threads and nut with a rust penetrant like WD40.



I cannot over-emphasize how important this is when installing the top nut to any shock or strut shaft, any brand. If the top nut is even a little loose, even a 1/16th of a turn loose, the shaft will act like a slide hammer and the top mount will rattle, make noise, and wear our the Teflon lining on the spherical bearing in just a matter of days. Then the sphericals have to be replaced. This is 90% of the cause of noise complaints we hear - improper installation of the strut top nut.



The method to install or replace the spherical bearings is tricky and isn't something you can do at home. We use a custom machined arbor press just for this procedure, which properly aligns the new spherical bearing into the bearing holder. Then we replace the retaining ring, and inspect the other parts of the camber plate. We sell thousands of camber plates a year yet only replace 2-8 spherical bearings per month, so the design we use has a very good track record for longevity. If we get a noise complaint and see a worn bearing, we always want to know why a spherical failed. We will ask questions from the customer to make sure it wasn't an installation issue - which it turns out to be about 90% of the time.

Last edited by modernbeat; 11-16-2016 at 05:41 PM.
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