After venturing more than 300 miles round trip to Mt. Carmel, PA for my 120K mile service, the Z ran smoother and stronger than ever before. With the confidence that my timing belt wouldn’t suddenly become interested in martyrdom, I drove around for a few days locally enjoying the nice weather. I still have my KONI struts set to the softest ride setting as I continue to break in my Shiro springs, and the car feels balanced with much less rear end dipping under heavier acceleration. Even with daily driver tires, the Z grips the road much more tightly and consistently.
All this to say, 3 days after my perilous journey to Xenon, I noticed a “clunking” noise coming from the front suspension during tighter turning and bumps. After restoring my entire front suspension (writeup / info to come, once this repair and rear sway bar end-link replacement are complete), the culprit appears to be the only two components not replaced – strut mounts and/or strut bearings, both of which were re-used after being cleaned up during restoration. I set about getting my hands on a new set of strut mounts to replace the original ones and complete my suspension refresh.
Strut mounts, from what I’ve learned, are a wearable component with a set lifespan. Over time the strut mounts can crack and deform, and at this age even well cared for Z31s will need strut mount replacements if they are seeing real world road usage. So, first try: Nissan OEM part websites, like this, or this, or this, etc. They all have confusingly similar names, to the point I forgot which one I ordered my clutch master rebuilt kit and slave cylinder from (lol). None of them have the strut mount, which isn’t surprising.
Next, reputable 3rd party parts sites, like RockAuto. The preferred brand of replacement suspension parts where available for the Z31 is KYB, but the KYB strut mounts are out of stock on RockAuto, as well as pretty much everywhere else on Earth (more on that in a bit). Here are the current options for strut mount replacements on RockAuto as of 1/2023:
Same thing at The Z Store. We know these parts existed at one time, they are currently unavailable, sucks to suck. There are always eBay options, but I’m a bit sketched out about buying parts from random Ebay vendors and hoping they fit, or are even for the right car. As a last resort fine, but I’d like the most possible assurance that I won’t need to do this repair twice.
In the mean time, I went out and bought a set of used OEM strut mounts from a 300ZX used parts site, either 300ZXpartsforyou (wonderful guy, located on west coast USA) or Vintage Z Parts. The set I got is in fair shape, but ideally I wanted new components to ensure the best operation and longest lifespan of the suspension. I kept searching for either the KYB strut mounts, or some other alternative, but found nothing. Finally, impulsiveness and past-tense FOMO got the best of me, and I found a site that claimed they had the KYB strut mounts in stock for a fair price, so I pulled the trigger and ordered two.
Again, relief was short lived. I got an email about 2 hours after my order:
We are currently back ordered on this until end of next month. Please let us know if this is okay. Thanks.email@example.com
Well, wheels are already in motion. I decided to throw good money after forever-on-backorder money and ordered a pair of the MEVOTECH strut mounts from RockAuto. As usual, they arrived on schedule, exactly as described, boxes and hardware intact. I will be comparing the OEM mounts I have in the garage with these new strut mounts to see if there are any noticeable changes to dimensions or fitment. The MEVOTECH strut mounts did come with strut bearings as well, but I previously purchased KYB strut bearings as well, so I will compare those as well to see if they are interchangeable.
So I have my parts, and the replacement shouldn’t be too bad, outside needing to break out my Harbor Freight spring compressor one more time after all the use it got doing my suspension overhaul. Minus that, we already broke all the fasteners loose and replaced most of the components, so the only concerns I have are removing and replacing the strut assembly without hurting the ball joint boots and other delicate pieces. I’ll add a part 2 once the repair has been done, as a write up for replacing the strut mounts and any hurdles along the way.