Community Forums

geofferyh · 08-21-2017, 09:49 AM

Boy has this turned out to be a project. I am trying to locate SAE 90W GL-5 Gear Oil in bottles, and not 5 gal. buckets or more.

My 2002 W22 chassis has front wheel bearings that run in SAE 90W GL-5 gear oil. The only thing I can find in the auto parts stores or Walmart is 80W-90 GL-5. And, some of these indicate "synthetic" and not "hypoid". My manuals specifically indicate "90W GL-5 Gear Oil", and nothing about brands.

Also, I Hate to mix unknown fluids, so if I drain the hubs, What to use? and how much will be needed in total to refill both hubs?

AKIQPilot · 08-21-2017, 10:25 AM

Quote:

Originally Posted by geofferyh

Boy has this turned out to be a project. I am trying to locate SAE 90W GL-5 Gear Oil in bottles, and not 5 gal. buckets or more.

My 2002 W22 chassis has front wheel bearings that run in SAE 90W GL-5 gear oil. The only thing I can find in the auto parts stores or Walmart is 80W-90 GL-5. And, some of these indicate "synthetic" and not "hypoid". My manuals specifically indicate "90W GL-5 Gear Oil", and nothing about brands.

Also, I Hate to mix unknown fluids, so if I drain the hubs, What to use? and how much will be needed in total to refill both hubs?

Ran into the same problem years ago when servicing the front hubs on our Itasca. An 80W-90 GL-5 will have the same viscosity as an 80wt oil when it's cold, say 0f and the the same viscosity as a 90wt oil when warm. If you ever use your coach in a cooler climate then you should consider the 80w-90. If you strictly operate in warm weather then maybe the straight 90 should be used.

I could not find the straight 90 when looking years ago. A little research showed that I would probably be better off with the 80w-90. I bought a couple qts of the 80w-90 and topped off my hubs. That was 10 years and 30,000 miles ago. No issues and I don't expect to ever see any.

IMO the front hubs don't see near as much heavy use as the gears in the rear. I think the 80w-90 is just fine for all climates.

donhoward49 · 10-16-2017, 01:27 PM

good info, i am in process of changing the Differential oil. I bought Lucas Brand 75-90 synthetic gear oil.. sounds like i can use the same in the front hubs when I get around to that..
Jeffery, how much did you use..

1doodadd · 10-16-2017, 01:32 PM

This is what you use in handy fill bottles.

https://www.amazon.com/s/?ie=UTF8&ke...l_1yorerx3oj_e

geofferyh · 10-16-2017, 03:32 PM

Quote:

Originally Posted by donhoward49

good info, i am in process of changing the Differential oil. I bought Lucas Brand 75-90 synthetic gear oil.. sounds like i can use the same in the front hubs when I get around to that..
Jeffery, how much did you use..

I have yet to drain and refill the hubs, so I don't know total needs yet. I will use Lucas Oil 10043 (Qt.) SAE 80W-90 Heavy Duty Gear Oil. This meets GL-5 Standard and more. Fill to the black level mark (circle) on the hub sight glass.

The recommendation to use Lucas Hub Oil (formulated to stop leaks in steering axles and trailer hubs on heavy duty trucks) is questionable in my mind, especially if the hubs are not leaking. Its spec. sheet doesn't call out any API GL rating. It might be OK in an emergency until you could get the hubs serviced.

Arch Hoagland · 10-16-2017, 05:49 PM

Are you low on lube or are you just changing it?

donhoward49 · 10-16-2017, 08:58 PM

Quote:

Originally Posted by Arch Hoagland

Are you low on lube or are you just changing it?

I was thinking to change it? Do I need to??

Arch Hoagland · 10-16-2017, 09:08 PM

I don't know of any requirement to change it. I'm at 87,000 miles with no problems.

donhoward49 · 10-17-2017, 04:47 AM

well, I might not do it then. I have plenty to do without making work. Thanks

70ChevelleSS · 10-17-2017, 05:59 AM

Unless the lube looks cloudy or milky there is no need to change it. Just make sure the hubs are filled to the line on the sight glass.

vettenuts · 10-17-2017, 03:09 PM

I believe Chevron makes the called for 90W lube. There is a supplier near me who has it.

C Hammonds · 10-30-2017, 04:15 PM

Years ago, we used a product called APG-80 and 90 wt. gear oil for outboard engines. As I remember, there was an issue with oils that would foam. So, the APG 80 was used in the electric shift lower units; it was a Lubriplate product. There was also what was called "Hypoid 90". probably nothing to do with this application, but it was a 90 weight gear oil and for extreme service.
Carl