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Cuppa
3rd December 2019, 01:32 PM
I bought our car with about 153,000kms on it. Wheel bearings had been replaced at 150,000km.

Since then I have checked & repacked them at around 165,000kms, & 203,000kms. On both those occasions there has been no noticeable play in the bearings.
Last week I checked for play again (230,000kms) & found the passenger side to have noticeable play, & the driver side had some play, but less than the passenger side.

Because I'm having issues with a bad back I paid for a local mechanic shop to check the bearings & either re-pack them or replace them with bearings I have been carrying with us today.

I got the car back with the bearings having been examined, re-packed & readjusted. They had determined that my new bearings weren't required.

Knowing now that the bearings were still good, I could have just adjusted them without re-packing, but of course it would have left doubts gnawing away at me If I'd done that.

Soooo....... I know the bearings were good 27,000kms ago, & have checked the wheels for play a couple of times since then & found none, & surmise that the play/wear I discovered recently has most likely occurred
in just the past 10,000 kms, most of which has been a mix of dusty corrugated roads & low range 4wd'ing.

I have no option other than to trust the judgement of the mechanics (having told them of our plans to be driving around Cape York for several months), although it is fair to say that had I been doing the job myself I would have erred on the side of caution & replaced them even if they had felt & looked ok.

So really my question is ..... If next time I again do the job myself ..........If the rollers in the cage spin without any graunchinness (after cleaning), & no scoring or ridging on the cups can be felt with a fingernail, no visual damage, & no 'blueing' from overheating will they still be ok to repack. For play to have developed there must have been wear, but if the wear is even & smooth - how does one know whether to replace them.

As I said I'll probably replace them anyway ..... but would like to know if there is any way to know whether they have reached their 'wear limit' in the absence of damage?

mudski
3rd December 2019, 01:40 PM
Best way to tell is to clean them right up so there is no grease and check. If there is no pitting, track marks in the bearing cup that you can feel, visible wear is ok, and the cage and rollers on the cone look good, then I would happily re grease and refit. I used to remove and check mine every 12months like this when it was a daily.

Cuppa
3rd December 2019, 02:33 PM
Best way to tell is to clean them right up so there is no grease and check. If there is no pitting, track marks in the bearing cup that you can feel, visible wear is ok, and the cage and rollers on the cone look good, then I would happily re grease and refit. I used to remove and check mine every 12months like this when it was a daily.

Yep, that's what I've done previously Mark, but I guess I'm wondering if it's possible to reach a 'wear limit' without damage. Maybe so long as the wear hasn't gone beyond the hardened layer of the rollers or cups it's ok, but I'm also wondering if anyone can pick when it's getting close to that point, & if so how to tell? Otherwise each clean & re-pack is a bit of a lottery.

pearcey
3rd December 2019, 02:58 PM
G`Day Cuppa.
The two biggest contributing factors in bearing failure, are. One, over tightening, bearing heats up expands, and just keeps getting hotter and hotter untill the metal fails. Two, over packing bearings and HUBS, Hubs full of grease get hot and again expands either forcing the seal out or and or letting the grease past . the grease out side the seal then gathers dust ,grit ,etc and as the hub or shaft rotates the dust ,grit works its way past the seal and mixes with the over filled grease in the hub and then works its way into the bearings. Of-course there are other ways a bearing can fail, even a slight nick on a cup during instillation can cause failure, bit if on examination it all looks and feel right it usually is.
Safe travels mate.

Cuppa
3rd December 2019, 03:13 PM
Thanks both Mark & Pearcey. I guess if my bearings are still good I must have been doing something right!

MudRunnerTD
3rd December 2019, 03:24 PM
Yes as stated by Others it really is just a visual. If there is no visual defect then repack them and tension to spec. IMO if there is Any track mark at all then for the cost i replace them.

mudski
3rd December 2019, 04:05 PM
As pearcy mentioned about heat. Look for discolouration from heat. If there is any, change them out. When the hardening starts to wear off the rollers and/ or cups, you will see it. Its noticeable.

Hodge
3rd December 2019, 04:14 PM
Hi Cuppa.
Few weeks ago I had my front wheel bearings replaced.
I got them replaced for 2 reasons.

1. I wanted them replaced as I've clocked over 50k since owning the car, and I can't tell when and if the previous owner had the replaced.
2. Got the replaced as part of my get-rid-of-front-wobbles check list. (which worked!)

Prior to this, as part of attempting to fix the wobbles, I had the wheel bearings re-packed, re-tightened and I checked the tightness my self several times. The mechanic deemed the bearings in very good condition when checked and re-packed. This was around 10,000 prior to replacement.

Lo and behold, new bearings transformed my car. It's very smooth now, I can definitely feel it and most importantly it got rid of the wobble/shimmy I had in the 90-95km/h range.

This to me shows, even though on surface something may seem ok. Even tiny underlying issues can throw up drama.

For sub $150 front pair of quality bearings, for me it's a no-brainer from now on...

10G
4th December 2019, 11:41 AM
Yep I'm with Hodge here, for the price, as long as you can get the bearings, just replace them. My truck's up to 165,000 and I don't reckon the bearings have ever been replaced. They will be shortly.

What about rear wheel bearings, anyone ever look at them?

mudnut
4th December 2019, 01:56 PM
Yep I'm with Hodge here, for the price, as long as you can get the bearings, just replace them. My truck's up to 165,000 and I don't reckon the bearings have ever been replaced. They will be shortly.

What about rear wheel bearings, anyone ever look at them?

Yeah, about 60000ks ago, the rear oil seals leaked. Before fitting the axles, I took the advice given and repacked the bearings with some green water resistant bearing grease. All still good.

Cuppa
4th December 2019, 02:58 PM
What about rear wheel bearings, anyone ever look at them?

Had mine replaced in May 2018 at 203,000kms shortly before we commenced our current travels. Had no idea if they needed it or not, but thought it wise to get this checked out before travelling remote. Bearings need to be pressed in/out,so wasn't something I could attempt at home (or on the side of a bush track somewhere). Turned out I caught them just in time. One side was showing signs of running hot due to lack of grease & the other side had just the smallest weep of diff oil getting past the seal. The bearings are a lot bigger than in the front, (not sure if yours will be the same as on my leaf sprung ute with higher load capacity than the rear coil models). The mechanic felt that given the weight we carry, & probably the weight previously carried when it was a Telstra vehicle that 200k was about what he'd have expected. Lighter vehicles could expect a bit more.