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
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 (http://www.amazon.com/gp/product/B002D3YSKU?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00)
Jason
use a real gasket
I don't have the assembly drawings but I certainly think a real gasket would be appropriate.
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.
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
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!)
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.
Requires a hub removal to remove ALL the old oil if going to synthetic
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.
I would make sure the inner wheel seals are not leaking while you're working on the front hubs.
For what it's worth you left the parts store with the oil I would have left with.
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.
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.
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.
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.
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.
nice they said that. They are wrong.
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?
They are standard on heavy trucks however usually the plug is seized in and the cap breaks before it comes free.
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.
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.
(https://www.foreforums.com/imagecache.php?image=http%3A%2F%2Fwww.hilineauto.com%2Fhuboil.jpg&hash=48513b80eac7e3b1caebc1b2b4cf5023" rel="cached" data-hash="48513b80eac7e3b1caebc1b2b4cf5023" data-warn="External image, click here to view original" data-url="http://www.hilineauto.com/huboil.jpg)
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.
I suppose you could call Foretravel and ask them yourself if it really bothers you.
The issue seems to be to use RTV or a gasket, I can never find the exact gasket, however cutting one from gasket material is very simple/easy. RTV has its place, but unless you are familiar with using it, would not recommend it as we have pulled engines down that had been RTV'd where the RTV had gotten into the oil pickup screen and that became an issue of no oil to pump. Not directly related to wheel bearings, but over use is not good, most weekend monkeys do not have the experience for proper use of it. Make a proper gasket.
But its your baby, so have fun.
It bothers me not at all. You started this thread which is entitled, "RTV or "real" gasket on front wheel oil hub?". Nearly 10 people responded to you and said use a real gasket--including guys that have done this stuff for many years. You choose to ignore this input and call up FT and who knows who you are speaking with...it may be a counter guy that's never turned a wrench.
Anyway, to get back on sealing stuff. I prefer #2 permatex as it doesn't harden like RTV. As dave mentioned, RTV breaks off and gets in bad spots and never disintegrates, especially in engines and fluid systems. #2 does well.
BUT, I pretty much exclusively switch over to anaerobic gasket makers like Loctite 515. It only cures where it is squeezed so any excess doesn't damage stuff. Also, it gives more time to assemble as it doesn't set up until squeezed. I used RTV the first time on my differential 3rd member install (I had to remove due to defective unit) and it was pain to clean. I used Loctite 515 the second go around and it hasn't leaked and was much less stressful to install due to no rush.
I called Foretravel to ask them what gasket to order after I agreed with all of you that I needed to order a "real" gasket. Foretravel told me not to because they have always used red RTV and it seals better than a real gasket. I never suggested using RTV to Foretravel, but they immediately suggested it to me. When I took my hubcap off I saw some of the old red RTV on there which is what Foretravel said they used. I'm not saying I agree with them. I would have used a "real" gasket if they hadn't told me to use RTV... and that's all I know about this other than the RTV seems to have worked... and I'm sure I didn't use too much RTV. If you disagree with Foretravel that's okay with me. I don't have anything at stake either way. I only added the information for the benefit of others who might read this looking for a solution. I always think I'm adding some important content that will benefit other readers but then I regret it and promise myself I won't post on here anymore... (sigh)
Found the stemco kit on ebay for my year,it has the red cap,the clear plastic piece,a seal,and a gasket.I would use a gasket
until proven it did not work.
Yes, please do... everyone please use a gasket.
I just had both front hub assembly's changed, because it seemed as thought they were weeping a little bit.The coach was in for a leaking radiator.(That is ordered).They checked over the major parts of the coach, airbags, shocks, brakes , all looks good.When I drove out he said he was not going to charge me for this visit.I believe the whole hub assembly(no bearings)was around $55.00 a piece, I could be wrong but for that cost its worth changing and it comes with a gasket.
Gasket material is pretty cheap at my parts house. I usually keep several sheets of differing thicknesses to make these types of gaskets. I also make (if I don't have a factory one) axle, thermostat, water pump, fuel pump, and/or pretty much any flat standard gasket. For me, it's just quicker and easier. ;D
TOM
Recently changed hub oil and researched the gasket,watched a Stemco video put out by Stemco,he specifically mentioned not
to use rtv as it can get in the bearing.Remember whatever oozes on the outside oozse on the inside also.Foretravel should have been using a gasket.
I like to use a gasket with a thin coat of Permatex 80019 Aviation Form-A-Gasket #3 applied to both sides. It allows for easier removal
of the two parts while leaving the gasket intact. That's not to say that it doesn't require some coaxing on bigger components like valve covers. In that instance I use a small block of wood under the lip and tap it with a hammer to get one end started.
I did exactly what Foretravel told me to do. I used the red high temperature RTV. It's been several years and several trips across the USA since then. The RTV hasn't leaked and the bearing hasn't had any problems. Call Foretravel and explain to them that they don't know what they're doing. I just followed their instructions.
Hey Scott - glad to see you're still posting, in spite of the flak.
I'm not saying what is or isn't correct, but when MOT did my front bearing replacement in Dec of last year, there was no paper gasket under the oil reservoir cover, just "red stuff", AND they reinstalled the cover with red RTV. Seems to be SOP with MOT.
Go figure...
Scott,you probably put the right amount on,from what I remember of the video they did'nt want somebody using the whole tube.
When I took mine apart I thought there was a worm inside there was so much silicone and it was clear.
Well now we are on to something I know a lot about. GASKETS. Having owned a gasket shop in east Texas for almost 20 years and made gaskets for Stemco in Longview. Things usually start out well and good. There are other things that take place over the years to change things.
1. The OEM manufacturer wants to save money and changes from one material to another.
2. A gasket material is substituted that is not compatible with the substance being sealed.
3. Someone along the way has tapped out a gasket on the flange (sealing surface) to be sealed and used a sledge hammer.
4. Improper torque. (Over torquing can warp faces) Inadequate prep of mating surfaces.
5. Gasket dressing is sometimes helpful on gasket surfaces prior to installation. On this I might just put a little antiseize on both sides of the gasket with your finger ir small brush.
6. Try and not re-use a gasket.
Good luck and have a great Sunday
John