front wheel bearing service interval

[356robo]

What is the recommended service interval (miles) for the front wheel bearing on a street only 911? ;repack or replace.

Thanks in advance,

Rob

[IROC]

Hard question to definitively answer, but on a street-only car, I would be tempted to go ahead and do it if you have no idea when the last time the bearings were messed with and then probably would only check them when replacing rotors, etc. As for repack/replace - if when you remove them and clean them they look OK, then simply repack and reinstall. Don't fix it if it ain't broke.

[Kraftwerk]

Was wondering the same thing... every 80,000 miles? Mine is a street only car (so far)

[spuggy]

Originally Posted by IROC

and then probably would only check them when replacing rotors, etc.

Factory workshop manual gives "check front wheel bearing" @ 6,000 miles for the '68 and 12,000 for the '69. Just sayin'.

I'm pretty sure they don't mean "grab the wheel and shake it" either - although any play detectable like that is way too much...

[IROC]

Originally Posted by spuggy

Factory workshop manual gives "check front wheel bearing" @ 6,000 miles for the '68 and 12,000 for the '69. Just sayin'.

I'm pretty sure they don't mean "grab the wheel and shake it" either - although any play detectable like that is way too much...

So you think the factory intended for owners to remove their hubs and clean and repack their wheel bearings every 6k miles (if they didn't mean "grab the wheel and shake it")? Maybe so, but how many people actually do that? And for those that do, how many find issues that require action? For those that don't, how many times does it come back to haunt them? I understand the factory recommendation (which I bet is a much longer interval for later cars), but having owned my car for 17 years and checked the bearings many times, I think a longer interval than 6k or 12k miles is pretty safe. YMMV.

For these cars nowadays, I still say to remove them, clean inspect and repack/replace as needed if you don't know when the last time it was done and then periodically check after that based on use, mileage, etc.

[Jesse16]

My knowledge of "bearings" and what I've been told by bearing manufacturers is that there normally is no "replacement" interval for bearings. (most normal applications which includes automotive) They are essentially designed to run "if clean" forever. The number of design cycles rotations is basically infinite. Only "unexpected failures or dirt make them fail. A brand new unit is just as likely to fail as an old unit. Basically, if you know they're dirty, doesn't hurt to clean them but you can also just keep them sealed and wait for failure if it ever happens. Of course, this doesn't include the non-metal parts like seals which do fail over time.
If you don't clean them well, you could make the situation worse actually by putting dirt into the system. My bearing philosophy is, never just take a bearing apart to replace or clean it without knowing there is a problem.

[Superman]

Bearings tend to last a long time, and replacing them for the heck of it is a bad idea. When they are bad, they make noise. That's when you replace them.

For routine maintenance, I would suggest removing the hub and at least having a look every couple of years. More often if your car gets driven through water/mud/snow. Be careful not to introduce dirt or contaminants. At least carefully wipe away dry grease, and spooge some new grease in there. For more persnickity guys, they can be cleaned and repacked. They're not easy to get clean. Again, make darned sure you are not introducing dirt. And be sure you put them back where you found them. Bearings and races are matched pairs.

[RWebb]

so, can we be pretty sure they will make noise before failing?

I wouldn't want a catastrophic failure with no warning...