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Topic: RTV or "real" gasket on front wheel oil hub? (Read 3163 times) previous topic - next topic

RTV or "real" gasket on front wheel oil hub?

I noticed a little bit of oil around the outside edge of the chrome baby moon hubcap on my front driver's side wheel and pulled it off to see where it was coming from. It appears the oil is seeping from the blue RTV gasket between the wheel hub and the aluminum Stemco thingy. It's not coming from the plastic window, or the red rubber cap, or the gasket behind the window. It looks like it's only coming from the gasket back near the hub itself. This brings me to my stoopid question. Is this really supposed to be RTV or is it supposed to be a "real" gasket? I looked at a parts illustration of a front wheel hub that Barry Beam posted on another thread but it doesn't show any gasket. The oil level is low in that wheel but I can still see oil down in there. Hopefully there wasn't any bearing damage. I'm going to refill it with 80W-90 because that's what the Rockwell manual says to use. I'll probably jack up that wheel and check to see how much play is in the wheel bearing and if it rotates smoothly or makes any noises. I'll also look at the used oil that comes out to see if there's any metal or debris in it. I noticed the Rockwell manual said to change the wheel bearing oil at 100,000 miles and I'm at 104,000 miles now.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #1

Scott

When I replaced my inner bearing  seal this summer I used the following gasket for the oil cap.

Amazon.com: Stemco Gasket 6-Hole 4024 330-3024: Automotive

Jason

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Jason
1999 U320 36'

Re: RTV or "real" gasket on front wheel oil hub?

Reply #2
use a real gasket
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: RTV or "real" gasket on front wheel oil hub?

Reply #3
I don't have the assembly drawings but I certainly think a real gasket would be appropriate.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: RTV or "real" gasket on front wheel oil hub?

Reply #4
I jacked up the coach and the wheel spins freely with no noise and no bearing play that I can feel. It doesn't seem like there's any bearing damage. I'll change the oil in that wheel bearing today because I need to drive the coach down to the grocery store tomorrow. It's a very tiny leak but it leaks all the time whether the coach is moving or parked, so I really should fix it... and I probably will next week... with a "real" gasket.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #5
Suggestion:
There are several vendors that can supply their version of HUB oil/lube.
AmsOil, Neo, Lucas, Royal Purple, etc., etc., all have excellent synthetic HUB oils.

As for changing bearings @ 100K.. nuts.  Change the lube and have a glass of your favorite adult beverage.
The steering axle bearings in my Class 8 lasted until it found a new owner @ 1.4 million.
I did replace the inner race(s) @ 350K (for piece of mind.)  pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Re: RTV or "real" gasket on front wheel oil hub?

Reply #6
Lucas hub oil has treated me well. I'd recommend refilling with it when you replace the RTV with a real gasket (my recommendation is for the proper, correct gasket!)
Matt
95 U300, 78k miles
Cat 3176 Jake Brake, HD4060.

Re: RTV or "real" gasket on front wheel oil hub?

Reply #7
It took me about an hour to clean off all the RTV some goon put on my front hub that was leaking. The gasket install took 30 seconds.
1998 U270 34'

Re: RTV or "real" gasket on front wheel oil hub?

Reply #8
Requires a hub removal to remove ALL the old oil if going to synthetic
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: RTV or "real" gasket on front wheel oil hub?

Reply #9
Rockwell says to change the hub oil at 100,000 miles but not the bearings, just to be clear. My bearing spins freely, doesn't make any noise, doesn't have any play in it, and it never ran completely out of oil so I think it's okay. I'll change the oil in both bearings and put "real" gaskets in. I just bought a quart of Lucas 80W-90 GL5, which was the best oil they had at the local AutoZone, the only parts store open on Saturday here in Los Alamos NM. I don't want to switch to synthetic oil unless I have good reason to do so.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #10
I would make sure the inner wheel seals are not leaking while you're working on the front hubs.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: RTV or "real" gasket on front wheel oil hub?

Reply #11
For what it's worth you left the parts store with the oil I would have left with.
Dub McBride 1996 270

Re: RTV or "real" gasket on front wheel oil hub?

Reply #12
When you get to the oil, get a small amount on your finger and wipe it across your palm.  Then look and see if it has an shiny (tiny) flecks like modern nail varnish.  If so you have a bearing problem.
I had one go bad on the old Grand Villa and it was only noticeable when a load was put on it, not by rotating it.
And, as has already been said use a "proper" gasket.
Brian.
2001 U320 Build #5865
Daihatsu Rocky Toad
VW Touareg
'82 F100 Stepside
Beech' Debonair

Re: RTV or "real" gasket on front wheel oil hub?

Reply #13
Also check the oil you drain out. let it sit in a tray so the heavy stuff drops to the bottom then when you pour it out to dispose any grit will be shining on the bottom of the tray.
Toby a 94 u280
Cummins 8.3
6 speed Allison
Exhaust brake


Adopted by Derek and Annabelle

Re: RTV or "real" gasket on front wheel oil hub?

Reply #14
Drive the tire on whatever side your doing up on a 4x4 or 6x6 whatever then let it sit a bit before you take hubcover off it will let the oil Drain back  in the hub and reduce the mess.Then roll off the board and top off as necessary.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: RTV or "real" gasket on front wheel oil hub?

Reply #15
It's time to change the oil in the front hubs (100,000 miles) so my goal will be to drain out as much of the old oil as practical, install "real" gaskets, and refill the hubs with fresh oil.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #16
It's time to change the oil in the front hubs (100,000 miles) so my goal will be to drain out as much of the old oil as practical, install "real" gaskets, and refill the hubs with fresh oil.

If all you are doing is changing oil (no leaks) you are going to WAY too much work.

If changing fluid, remove the red center plug (no tools required).

Use any suction device (I still have my 30 year old transmission pump-- a $7 investment).

Suck out as much as you can.  Overfill (up to bottom of hole).  Suck it out again and refill to proper level.  Next time it is convenient, do the same. 

Total oil used-- less than one quart.  Total time less than 20 minutes.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: RTV or "real" gasket on front wheel oil hub?

Reply #17
I have a small leak, which was mentioned in the original post. I called Foretravel's parts department today because I wasn't sure what gasket to order and I wanted an exact part number. I was told to use RTV instead because that's what they've always used and it seals better than the "real" gasket. In recent years they have switched from blue RTV, which is what mine has, to red RTV because of the higher temperature rating.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #18
nice they said that. They are wrong.
1998 U270 34'

Re: RTV or "real" gasket on front wheel oil hub?

Reply #19
The red high temperature RTV seems to work. It's been a couple of weeks and still no oil leaks. I drove about 20 miles to the grocery store and back last weekend and the oil level is still the same. I didn't disturb the other wheel, which still has blue RTV on it but it's not leaking at all. When I took the hubcap off the leaking wheel I noticed the outer wheel bearing is completely exposed and any debris disturbed while cleaning off the old RTV can go right into the wheel bearing. The risk of contamination didn't seem worthwhile if there isn't any leak to fix. I did change the oil in both wheels because it may be over 100,000 miles... but I doubt it because I noticed some red RTV under the blue RTV so it's been disturbed previously. Foretravel told me they use red RTV at the factory. I looked in with a flashlight at the bearing on the leaking wheel and it appears to be in perfect condition with no discoloration. There wasn't any debris in the used oil from either wheel. I jacked up each wheel and can't feel any play in the bearings. I thought I'd feel a little bit because cars and light trucks always have some. I spun each wheel and there aren't any noises except the brake rotors contacting the pads slightly, which is normal... So now you have the results of my unscientific testing. It looks like red high temperature RTV works for sealing front wheel hubcaps, and that's what Foretravel said they use.

Oh, and my hubcaps have little pipe plugs in them for draining out the used oil, so I didn't use a suction pump. I believe those pipe plugs are an extra cost item that can be special ordered. Do other Foretravel coaches have those or did a previous owner install them on my coach? Maybe that was done when they used the blue RTV?
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #20
They are standard on heavy trucks however usually the plug is seized in and the cap breaks before it comes free.
Toby a 94 u280
Cummins 8.3
6 speed Allison
Exhaust brake


Adopted by Derek and Annabelle

Re: RTV or "real" gasket on front wheel oil hub?

Reply #21
Wow, that's surprising that a pipe plug in oil would seize. Mine came right out when I tapped on the Allen wrench with a hammer. It appeared to have red RTV on the threads intentionally, like you'd put pipe dope on the threads, so that's what I did when I replaced the plug. The red RTV was probably from Foretravel when it was originally installed. Hopefully the pipe plug will come out years from now when I have to take it out next time.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: RTV or "real" gasket on front wheel oil hub?

Reply #22
Mine also came right out when I drained them. No sealant on my threads, but the oil was pretty bad. A newpig form a funnel makes the job a clean piece of cake.

Matt
95 U300, 78k miles
Cat 3176 Jake Brake, HD4060.

Re: RTV or "real" gasket on front wheel oil hub?

Reply #23
I doubt foretravel uses any rtv at the factory when they build the coach. Why would I say this? Because I would wager the axle comes complete with hubs installed from meritor and ft just bolts the assembly on the coach.
1998 U270 34'

Re: RTV or "real" gasket on front wheel oil hub?

Reply #24
I suppose you could call Foretravel and ask them yourself if it really bothers you.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)