Have a 2010 Mazda3, equivalent of a Japanese Ford Focus and the car has strut bearings. Replaced the original ones last year, about 130k miles. Front left completely shot, pieces falling off (its made out of plastic), ball bearings missing and completely dry. Replaced both fronts with Moogs, because they were cheaper and thought Moog is better than other aftermarket suspension brands, before installing them I opened them up and saw that they could use more grease so I packed some more in with this grease I had on hand.

[img]https://contentinfo.autozone.com/znetcs/product-info/en/US/vlo/VV614/image/4/[/img]

Seemed to fix the noise issue for about 6 months but the noise is back. Decided to get OEM strut mounts but am wondering if me adding more grease to the Moog ones had a negative effect and whether I should do it to OEM strut bearings. Should I just leave them be or is there a 'best' grease for packing strut bearings?

I was waiting for what others might have to say but, no one is replying. Here's my take on this.

Putting grease in the strut mount "probably" isn't a bad idea however, putting in the correct grease is more important. IDK what type of grease the manufacture of the strut mount slaps in there. But, what I am thinking is that the grease that they use is most likely a silicone type(or synthetic) and not petroleum based. Petroleum deteriorates rubber and this may be part of your problem with the strut mount(s) falling apart.

And though we're speaking about strut mounts and not brakes, this is one reason that it's best to use a silicone brake lube on brake caliper sliders etc., so the rubber boots don't disintegrate/fall apart ...IDK, just saying!


Good luck,

CB

EDIT:
Also, over tightening the mount(top bolt) to the strut could also be another issue you're having with the mount falling apart. Tighten but not over tighten!

You did nothing wrong except for using garbage parts, as long as you didn't forget a seal or spacer (if used when you put it back together. Those are 2 piece bearing shells and the grease you used is fine, they are a low speed high load ball bearing.
Get OE mounts and assemble as they come unless otherwise specified by the FSM, the originals went 130K the new ones will too.

Agree....bought the wrong brand of parts...


Moog is just coasting on the name now....most of it is garbage.....

Moog was one of the best in the business, now they rebox some real tat for all over the third world.
I got some bushings last month that were so poor I wouldn't even put them on a car, instead I ordered some poly made by a South African family company PSB and some from Power Flex.

The Power Flex VW strut mounts are the bar non and PSB make a nice rear carrier bushing, that has a good precision fit.

https://psbushings.com/

https://powerflexusa.com/

So when shopping for a grease for repacking strut bearings what kinds of grease and kinds of test numbers should I be paying attention to? I figured extreme pressure greases because struts can be submitted to high load conditions, like on bad roads with lots of potholes but also low-speed torque like when turning the wheel left or right.

For that particular type of bearing (very low speed, high load) I would use a 5% moly grease like Schaeffer 238.

OR for a high load and slow speed you can have great luck with a Texas Refinery (TRC)

880 Crown and chassis with MOLY

There is none better.