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Rear axle bearings - sealed or unsealed?
Danno66 - June 16th, 2013 at 07:31 PM

My '67 project will be lowered either one outer spline or one inner ( haven't decided yet ) but it will no longer always have the axle tubes sloping down so I am worried that the bearings may dry out. What do people think of sealed bearings or what life should I expect if my camber is always zero or negative?

Thanks, Dan


lou0060 - June 17th, 2013 at 08:14 PM

unless it is super super low you shouldn't have too many issues. Bearings must have lubrication and oil/grease starvation can lead to almost instant failure. Even with a bit of negative camber oil will work its way down, or up, to the bearings as you go round corners etc. If you are going really low or will do lots of long highway miles without much cornering then maybe sealed bearings would be better but doubt a couple of notches will be that servere. otherwise do the F1 weave left to right and that'll get the oil out to the wheels.....


Danno66 - June 17th, 2013 at 10:34 PM

Thanks Lou!
I have also heard people use sealed bearings but pop the inner seal out. This ensures oil gets to the bearing but the remaining outer seal ensures oil NEVER leaks onto the brakes if the O rings etc fail. .........I think thats a pretty GOOD idea!


vwo60 - June 18th, 2013 at 07:44 AM

Just pack your standard bearings with high temperature wheel bearing grease that is compatable with your gear box oil, works in the front wheel bearings.


68AutoBug - June 18th, 2013 at 01:06 PM

Quote:
Originally posted by vwo60
Just pack your standard bearings with high temperature wheel bearing grease that is compatable with your gear box oil, works in the front wheel bearings.



Hi Dan,

Front wheels don't have any oil??

plus there are two roller bearings in the front wheel hubs..
not a ball bearing.. and the oil would dilute the grease eventually... if using grease make sure its Lithium based MOLY grease... MUST Use this grease..
chassis grease is crap.. clay based usually...

I haven't read of anyone on here complaining of wheel bearings
wearing out prematurely because of low oil or no lubrication..

I would just leave it to the oil to lubricate the bearing..
just make sure the gearbox is full of Hypoid oil...
also a MUST USE oil...

make sure the bearing is a C3 and leaving one end sealed is a good idea..

cheers

LEE


vwo60 - June 18th, 2013 at 06:43 PM

If you leave one seal in how do you lubricate the original seal. if the grease is compatable with the oil it does not matter, just gives you some more protection.


68AutoBug - June 18th, 2013 at 11:34 PM

Hi

You would need to put a small amount of oil between the lips of the seal so they are lubricated..

I do that with all oil or grease seals otherwise they are dry and wear down fast until the oil or grease can get thru the inner lip..

and the grease [lithium based MOLY grease] won't hurt anything

cheers

LEE


Danno66 - June 20th, 2013 at 12:31 PM

Thanks for all the advice guys :cool:

OK, so I have just bought a pair of NSK sealed bearings 6306DDUCM
(Japanese quality so they should last a while ). I will pop the inner seal off, pack some more grease in and see how they hold up. Watch this space!

Cheers, Dan


68AutoBug - June 20th, 2013 at 12:50 PM

Quote:
Originally posted by Danno66
Thanks for all the advice guys :cool:

OK, so I have just bought a pair of NSK sealed bearings 6306DDUCM
(Japanese quality so they should last a while ). I will pop the inner seal off, pack some more grease in and see how they hold up. Watch this space!

Cheers, Dan


should have been C3 on the end of the bearings Dan
C3 are quality controlled or have finer tolerances..
but You should be OK... with Japanese bearings...

cheers

LEE


lou0060 - July 23rd, 2013 at 09:27 PM

sorry been missing this thread.

Lee, you shouldn't mix up lithium grease with moly grease. Lithium grease is def the way to go as it is formulated for "rolling " bearings. Use an EP2 Lithium grease. so called "moly" grease is a molybdenum disulphide grease and it actually is not suitable for rolling type bearing such as ball and roller bearings. It contains mircoscopic Mo2S particles which are actually harder than the bearing surfaces and if larger than the film of lubricant seperating the balls or rollers from the raceways can cause wear. This type of grease works well in sliding type bearings, CV joints, bushes, etc.

the C3 is a bearing with slightly higher internal clearance. Not so much more precision but actually more internal clearance so that when it get s hot is does not preload itself too much. It is commonly used in alternators and such which tend to run hot due to their environment.


hope this helps.


vw54 - July 24th, 2013 at 07:00 AM

Louie IS the Bearing Genius


HappyDaze - July 24th, 2013 at 10:07 AM

Good info. there, lou0060. Not many people - even those using bearings every day - know what those 'dots' or 'diamonds' mean.

Furnace or oven circulating fans run really big clearances when the shaft temp. is much higher than the casing. Some car manufacturers fit 2 or 3 dot bearings to allow for slight misalignment or flex in axles, and not so much for temp. differences.

It's interesting how they make the 'clearance' bearings.....the grinding is the same as standard bearings, but the temperature is varied for each different clearance.