wheel bearing oil bath.

[Jeremy Parrett]

      Need to know how much EP SAE 90 gear oil  is needed to drain and refill my 4 wheel bearing oil baths.

[Gerald Farris]

Jeremy,
If you are going to completely drain, replace the seals, and refill your steer and tag axles, it takes a little less tan a quart per axle. However, if you are just going to drain the oil at the drain plug in the cover, it will not take that much and a quart may do both axles.

Gerald   

[Mike Groves]

Gerald,

Last year I was quoted for draining and replacing the oil in my front axle of my '99.  I remember it being quite expensive but I forget right now how much.  Where does one drain that oil?  Sounds like something I could do easily based on your post.

Thanks,
Mike

[Edward Buker]

Mike,

There is a little plastic screw plug near the hub rubber cap. You move the coach until that is at the lower part of the wheel nearer the ground, unscrew and let drain. You fill through the rubber cap after pulling it. Be careful not to over tighten the drain plug, threads are plastic. Rubber cover has to be pushed in and fully seated all the way around. I think both front hubs took less than a quart together if I remember right.

Later Ed

[Mike Groves]

Well, I'll have to see if that cap comes off easily then.  One would think so since it is a cap to an oil reservoir.  I think perhaps the dealership didn't really understand my front hub system.  It may have been a question that I asked over the phone but it seems that I remember them saying to "to get all the oil out we have to remove the hubs" or something like that.  I think this may be the only item I've not changed the fluid out on since I bought the coach in September of 2013.

Thanks Ed,
Mike

[Gerald Farris]

Mike,
Draining the front hub oil through the drain plug in the front hub cover does not get all of the oil out, but you get 2/3s to 3/4s of the oil out, so you are not doing a complete oil change, but it is quick, easy, and cheap. To get all of the oil out, you have to remove the front hub and rotor assembly and lay it face down to drain all the oil. When I changed the front hub oil in my coach at about 135,000 miles, I removed both front hubs, drained all oil, replaced both front brake rotors, replaced front brake pads, and replaced both front hub oil seals.

If you change your hub oil, only use a full synthetic oil.

Gerald     

[Edward Buker]

Gerald thanks for pointing out the need to go beyond the simple drain and fill of the front hub oil using the method you described. It is a comprehensive brake evaluation and hub oil change that is really the best method.

Given you do not have the means to remove the wheels, and you are attempting to do this yourself, you can improve the oil bath that is left behind by flushing the hub with extra oil while the plug is left out. This is not as good as the method Gerald describes but it is better than a simple drain and fill, and it will at least replace the majority of the old oil.

Also doing this procedure after driving the coach for a few minutes before hand will allow any contaminants that may have settled in the bottom of the reservoir to be in suspension in the old oil. The intent of this post is to not have you neglect the hub oil change completely if you do not have the means to pull the wheels. Changing the majority of the oil will extend the bearing life over leaving old oil in the hub. If you have the means indeed pull the wheels.

Later Ed

[Jerry Emert]

Sounds like it would be cheap (relatively), easy and efficient to do it the easy way and just do it two or three times.  Each time you replace the oil it would be a higher percentage of new with the old oil.  Kind of like they say to do when changing transmission to Transynd.  Just sounds like a good idea to me.
Jerry

[Jeremy Parrett]

I like the quick method !  Reckon on doing it three times to get most of the old oil out.  thanks for all the advise.

[Mike Groves]

Thanks Gerald for restoring the faith I had in my shop, which is a Pape-Kenworth near Wilsonville, Oregon.  I guess they took me quite literally as you've described.

Mike