NetFurie

Anyone have any idea as to what could cause strut bearings to break... a lot? I replace them and 3 months later I hear the annoying clunk of the spring winding and slamming back into place.

I've been lowered on Illuminas for the past 6 or 7 years. Very modest drop. But in the last 2 years or so these bearings just keep shredding.

I've tried replacing the mounts and I've made sure both surfaces are very clean before putting in the new bearing. The top nut is torqued to spec (50 ft-lb). I've also tried removing the strut tower bar.

What else could be causing stress in this area?

Doomi30

iTrader: (1)

very bad luck?

Nealoc187

iTrader: (23)

did you replace the mounts with other used mounts, or were they brand new oem mounts?

it's a long shot, but I can't see how anything besides the condition of the mounts would affect this.

are you sure you're installing them correctly?

NetFurie

I bought new mounts (from Nissan) when i put on the illuminas several years ago.
When the bearings first shredded 18 to 20 months ago I just replaced the bearings (from napa).
4 to 6 months later they broke again so i bought new bearings and mounts from autozone.
Few months after I bought just the bearings from Nissan.
3 months ago the driver side went again so i just replaced that.
Now they're both gone again.

I'm pretty sure I'm installing them correctly; lip on the bearing is facing up.

Alignment maybe? It has been a while... don't know if that has anything to do with it or not but I'll give it a shot. Tire wear is even though and it's not pulling.

njmaxseltd

iTrader: (19)

I've never heard of that bearing shredding like you say. I've reused old bearings after disassembly and a regrease with no problems either. Something isn't right with your suspension install for those to be going bad like that. Is the upper spring perch clocked correctly? OUT stamped on the top faces out and is in line with the struts lower mount flange? Have you ever changed the rubber spring seat on the upper perch?
The torque of the top nut puts no load on that bearing. The weight of the car on that corner is the load on the bearing. The top nut only secures the strut to the mount. The upper perch is held up against the bearing by the spring and the weight of the vehicle.

JtzMax

iTrader: (5)

This is interesting, I don't have any idea what could be causing this, so I will not even speculate, but I'm gonna follow this thread to learn.

I really don't think it has anything to do with alignment though - how would it?

Nealoc187

iTrader: (23)

there's no way alignment could cause it. the strut bearing must be not getting seated correctly or some part is faulty/damaged/not installed correctly.

NetFurie

No, I've never changed the rubber seat. Aside from the strut and spring the only things I've changed are the mount (insulator, not the bracket), and the bearing. Everything else is original. Looking at the FSM exploded diagram again I may be missing the spacer at the top... unless it's just stuck up inside the wheel well.

As far as the perch... i paid attention to this when i first replaced the strut/spring. But to be honest I didn't even think about it when just replacing the bearing or mount. Since I didn't have to touch the perch I just assumed it was in the correct orientation. But this may explain it. Thanks for the tip.

WhiteMaxima9600

not sure, but for the annoying clunk turn up the radio works for me.

JtzMax

iTrader: (5)

Awsome! Turn up the radio .... as opposed to fix the problem, interesting.

NetFurie

I replaced both mounts and bearings again tonight. the old mounts looked pristine but I swapped them out anyway.

Also, "OUT" on the perch was indeed facing out on both struts (inline with the bottom mounting bracket). The bad part is that "OUT" was mostly scraped off. And I could see a corresponding scrape mark from inside the wheel well. I can only attribute this to the missing spacers for which i could find no trace of. I'm guessing this must have been allowing some lateral forces that destroyed the bearings?

Autozone didn't carry the spacers so i made my own out of some gasket material that was probably an eighth of an inch thick. This will just be temporary until I can find the actual ones.

I don't know if i just forgot to put the spacers back when put on the illuminas several years ago... or if they just got destroyed and fell out. Anyone know what they're made of?

jdooley

The "spacers" you mention are actually, really, just gaskets. They will typically glue themselves to either the underside of the strut tower or to the upper strut mount. So if you didn't notice them they maybe stuck in there. I doubt there presence is important for pops or clunks it most likely seals inner fender water from getting into the engine compartment and/or getting between the two parts and corroding them.

njmaxseltd

iTrader: (19)

The spacers you refer to are indeed just gaskets. Great job in making them yourself. I did that years ago when mine tore. The fact that your upper perches are scrapped tell me that they were not clocked correctly at some point.

Do you have a picture of the distroyed bearings you took out? Post them???

NetFurie

I do stil have the bearings i pulled out. I'll take some pictures when i get home.

Perhaps the scraping on the perch was a result of the broken bearing... and not the other way around.

At any rate, I took the car in to NTB to have it alligned. I understand it should have nothing to do with this problem but it had been a while... plus it's free (5 year warranty). I also asked them to take a look at the strut and anything connected to it. They couldn't find anything wrong with my strut installation but they did find two bad motor mounts. I wish I undertood all the mechanics under the hood so i could quit asking stupid questions.. but could bad motor mounts contribute in any way to an unstable strut?

As an aside, they want 650 to replace the two motor mounts. I couldn't find a write-up on how to do this so i'm still searching. Is 650 way too much? On a scale of 1 to egr tube removal how difficult a DIY is this?

Thanks,
Gavin

Trini Boom

iTrader: (5)

Umm yeah guy $650 is highway robbery. The mounts are $100 each OEM and only takes a few minutes to replace. Which mounts were they referring to?

eFLO

iTrader: (2)

you can even go ebay with the mounts, ~100 all four, i don't think anyone has had problems with them..not sure how hard it is but i believe u have to drop the crossmember if it is the front and rear mount.

NetFurie

They said the right and front mounts were shot. I wish i had the car in front of me to see exactly how accessible these are.

JtzMax

iTrader: (5)

First, let me start by saying - there are no stupid questions, ever! If you don't know, then you don't know. No shame in it, and once you ask the question, then you do know! And knowing is half the battle, right? GI JOE! WooT - sorry, childhood moment. lol

Anyway ... for the mounts, no way it would cause bad struts, if anything it'll ruin your axles or the other mounts, but that's it. To check the mounts, you'll need about 2 minutes of time and your eyes. Start the car (park or parking break on), pop the hood, grab the throtle cable, give it a short pop and watch the engine. If it rocks excessivley (front to rear / rear to front) then that shows bad mounts. You have 4 total and you can only see 3 of them (the one on the DS is actually a trans mount). The 4th one is on the back side of the block (by the firewall). Watch as you pop the throtle and see how much play you see. As far as replacing them, it's not that hard. And $650 is wayyyyyyy to much IMHO for that job. You drop the cross member and they are both right there. The front one you don't even have to drop the X member. I'd say it's a 6 / 10 (10 being hardest). Anyone else agree?

Trini Boom

iTrader: (5)

The right one meaning the passenger side mount? Also, the front mount, you will need to check to see if you have the regular one or the electronic controlled mount.

njmaxseltd

iTrader: (19)

Yes

NetFurie

Great. Thanks for the info! I'll try and tackle the mounts this evening. I found a write-up on another site for the maxima. Looks straight-forward enough with the hardest parts being busting the bolts loose and realigning the holes.

So, I'm still stumped on the strut bearing issue. If they break again soon I'll have some shop do it. I can't fathom how i could have screwed up the install but there doesn't seem to be another explanation.

NetFurie

I guess so. NTB just said "right" mount. I checked the FSM... I presume they mean the one up by the timing chain. But I'll confirm when i pick the car up.

StevieB

iTrader: (1)

A couple of years ago I completely trashed a new strut bearing within a few months after installing a Tokico HP suspension-I deduced it was from overtorquing.Unless your torque wrench gets calibrated regularly, the torque reading could be noticeably off, as was mine.The FSM torque spec range for the top strut bolt is 43-58 ft/lbs. I'd suggest you torque it to 45 ft/lbs and give yourself that much more margin.

NetFurie

Here are the beauties.

Trini Boom

iTrader: (5)

^^^ jeez, never seen bearings in that condition even if it was the original one for years....and this is only a few months?? You have a serious problem. Lets hope the new ones don't wear out that quick.

JtzMax

iTrader: (5)

That'll buff right out man, what's the problem?

njmaxseltd

iTrader: (19)

You sure you're not putting them in upside down? Never seen anything like that in all the suspension work I've done on 4th gens. The lip goes up, and the mount sits down on the bearing.

Again, the top nut doesn't put any load on the bearing. The top nut only secures the strut shaft to the mount. The bearing is literally held in place by the force of the spring pushing up on the upper perch and the weight of the vehicle once it's down on the ground.

NetFurie

Yep. The one on the right was in the car for 3 months. The left for 6 to 8 months.

And again, everything was fine for 4 years after the initial install of the Illuminas. It's just been in the last 18 months this has been such an issue.

Trini Boom

iTrader: (5)

Hmmmm......I went back and re-read this thread and noticed something missing after what mjmaxseltd stated here.


What springs are you using? The OEM or you bought a different set?

NetFurie

yeah... I'm positive I'm putting the bearing in correctly. It sits flush against the perch (upper spring seat), then the lip fits up inside the mount. The only thing that makes sense to me is something is allowing lateral movement in the knuckle... thus trying to bend the strut and putting stress on the bearing?

NetFurie

I can elaborate a little on my opening post... I lowered the car on Tokico Illuminas several years ago. These struts came with lowering springs. If I recall, it's about a 1.5 inch drop. I chose the illuminas because it was a relatively minor drop and I didn't want to sacrifice too much comfort for sportier ride.

njmaxseltd

iTrader: (19)

Their definately in right.

If you had that much movement in the knuckle you would have serious drivability issues.

I'm at a loss as to whats causing your failure.

speedofsalt32

why don't you put your strut together, exactly how you put it together inside of your vehicle and take a picture of it from a few angles, to help us help you diagnosis the situation