Tag Axle Oil Level?

[swebster]

OK...got one for the 325 and longer crowd. My 86' 345 has Alcoas with those big truck style chromed axle covers on both the rear drives and tags. The covers on the drives are completely enclosed one piece units but the covers on the tags have those little clear plastic plugs in the center with a smaller rubber plug within the plastic plug (I've seen these on commercial trailers before). They have two circular graduated lines on the clear plastic for an oil fill level.

What concerns me is that both sides are bone dry. So dry in fact that I don't think they have ever had oil in them. I just noticed this fact after putting nearly 3000 miles on the coach (without any obvious issues with the tags).

So what gives? Is oil supposed to be in there? Are they simply a truck stop replacement and I can ignore the fill lines? Again, without the coach/chassis manual (yet) I'm guessing at this kind of stuff.

As always everyone's advice is welcome and appreciated!

[ViewRVs]

I actually have some paperwork on the tag-axle. I will be busy doing other things so kick (PM) me if I forget to check my documentation!

[uncleneal]

Fred,
Please post what you find out. I have an 85/86 345 with the same covers on the tag axles, but no plug in the hole. When I filled them with 90w gear oil, it just runs out past the lugs everytime I move the coach. I plugged the holes with electricial knockout plugs and duct tape - couldn't find the plastic plugs. A friend has an 86 345 - his has solid caps, and regular trailer type wheel bearings with grease.
Thanks, Neal

[ViewRVs]

I dug through all my stuff at home and I didn't find it. I think I stuck in one of my overhead bins. We are going over to the storage center tomorrow so I will check!

[cooperhawk]

I have a 1984, 345 Motorhome. I have the solid covers on the tag axle wheels. I have taken them off to check the brakes and found that the axle has the standard wheel bearings similiar to the front wheels or trailer wheels. No place to oil.

[swebster]

Mine appears to be the same (greased bearing trailer axles). Now I'm wondering how these axle covers got on there and if they were original AS was there a reason for them?

[uncleneal]

The reason may be as simple as that's what they had available when they built the '86 model. Seems like I've seen one that had rubber plugs that had the Airstream logo on them.
My xeroxed service manual gives a good bit of info about the tag axle brakes and the air suspension system, but dosen't say anything about the bearings or lubing them.
You could do like I did and put some oil in there. If it runs out past the lugs like mine did, it obviously dosen't have a seal to keep it in, and wasn't intended to have oil in it. Makes a fine mess on the Alcoa wheels.

Neal

[swebster]

I suspected this too. Perhaps they were a replacement at some point. Both rear covers seem to be SS and look fine the fronts are chrome and have rusted badly. I've taken to browsing the "chrome" ailses at larger truck stops and even online looking for replacements for the front (along with lug covers) and perhaps the tags now as well.

I've always wanted to do that - now I have a valid reason to! All of those bolt on lights and chrome...I can't help myself, I just steer over there.

[ViewRVs]

I dug through my 345 yesterday and could not find the paperwork I thought I had. Sorry.

[swebster]

Fred,
Thanks for looking. I think those of us that have looked all think that the tags are just greased bearing axles. Not sure how these hub covers got on there but I feel safe to replace with solids after looking at the hub itself.