Wheel bearing grease

[tasdrouille]

I'm changing my rear brakes on the TDI, and will also replace the wheel bearings while I'm there.

What in your opinion would be the best grease to use from a rolling resistance standpoint? I don't mind having to repack the bearings now and then. I'll need something that performs well during our cold winters.

Thanks,

Martin

[justpassntime]

You need to use wheel bearing grease. The reason...it is designed for high temps and any other grease will turn into a liquid when the bearings get hot and they do get hot.

[tasdrouille]

How hot do they get?

I would normaly use a grease like this one

The temperature range for this grease is -22F to 250F

But could I get away with this one instead?

It is rated for -58F to 230F and has much better friction properties. Since my daily commute is only 7 miles and we get attrociously cold winters, my bearings dont get usually very hot. However I sometimes do couple hours highway trips in the summer too, but the ambient temperature never gets really higher than 90F.

[MetroMPG]

Subscribed... nothing to offer, but interested in the advice.

[tasdrouille]

I have found an SKF document stating that both those greases are compatible. Could I just mix the 2 and come up with an hybrid grease? Or just take the LGMT3 (the standard one which is a third less expensive than the low temp LGLT2) and mix a bit of low viscosity oil with it?

[tasdrouille]

I work for one of the biggest industrial components distributor in Canada. I just wanted to see what people have to say here before I talk with one of our engineers.

[Johnny Mullet]

PENNZOIL 7772 WHEEL BEARING GREASE

[Concrete]

IMHO, grease doesn't mean jack, unless you use the wrong stuff!

I agree,
I appreciate the effort but this will be immeasurably small advantage
but there is potentially a lot at stake - like not rolling - that has to hurt FE
I would go with the first one and call it good.

Or just take the LGMT3 (the standard one which is a third less expensive than the low temp LGLT2) and mix a bit of low viscosity oil with it?

sounds risky to mix this sort of thing - it will not give you an average viscosity
you are likely to just get two lubricates still separate but swimming together

also when considering temp is not just rolling friction temps.
It is the temps generated you emergency stop from highways speed
or if you have to ride the breaks a bit on a long decent in the mountains.
you sure don't want to it to start drooling out the side of the bearing

I would like to hear what an engineer in this area thinks they can do for you
----Especially if it is Moose Drool

[Bror Jace]

tasdrouille, given your location (Great White North) and driving habits (modest trips) I'm 99% sure you'd be fine with the slightly thinner wheel bearing grease ... even if it doesn't mention automotive applications.

I'm a charter member of BITOG and have dealt with lubrication topics for nearly a decade. The thinner stuff should be fine. If you are repacking these yourself, I would monitor them every couple months and look for signs of leaking. If the grease stays in place, I'd clean and inspect them in 25,000-35,000 miles just to be sure everything’s doing OK.

Just remember lithium is a soap and lithium-based greases WILL foam-up and wash out if allowed to come into contact with water spray. So, sealing is critical and even a minor leak will allow moisture into the bearing and degrade the grease quickly.

BDC, I would imagine sphere-shaped bearings would have less friction … as the contact surface would be a lot less than roller/needle bearings … but I’d be concerned about load and the spheres scoring the contact surfaces.

Frank Lee has got it right, though. I’ve seen systems for trailer bearings that allow you to use a bath of gear oil to lubricate the bearing unit (instead of grease). It’s supposed to reduce operating temps, increase unit life AND increase fuel economy.

Remember, grease is a lubricant mixed with a hard soap/paste to try to keep the lubricant in place. If you are able to keep lubes (such as gear oil) in place without resorting to drag, you are better off (regarding rolling resistance) without the solid compounds. Using Google quickly, I was unable to find one of these systems as an example.

My pick … if I could have any grease in the world? Schaeffer grease:

Schaeffer Lubricants | Heavy Duty Moly Grease

#274 Moly E.P. Synthetic Plus Grease – NLGI #0

Better low temp and high-temp performance. If Schaeffer prints it, I'm willing to believe it.

[tasdrouille]

Thanks for the useful and interesting replies.

Our engineers looked for a suitable moose droll based grease, but the pour point of the base fluid is way to high for the application...

As others mentioned, the grease is apparently no big deal. Nonetheless, I went with Timken synth industrial grease which is NLGI grade 1.5 with a -50F to 356F operating temp range and a very high viscosity index. So it may make a small difference on short cold start trips. I chose this specific one mainly because I can get it for cheap.