Skip to main content ↑ ↓
Topic: Front wheel seal replacement on my 99 U270 (Read 1224 times) previous topic - next topic

Re: Front wheel seal replacement on my 99 U270

Reply #25 –
I have a lot of trouble believing that the correct end-play will affect wander.  We are talking about .001- .005". Can not understand wanting to go from .001" to zero or pre-load. 

Neither bearing nor axle manufacturers recommend this (if they do, please post link).
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: Front wheel seal replacement on my 99 U270

Reply #26 –
Quote from: Dave M –
Bob,
Tell us about the "Legal" adjustment as referred to wheel bearings per your "expert Foretravel mechanic"
Always learning new Legal requirements.
Tnx

The stemco video referenced here a while ago shows the seal installation and settings.

The narrator mentions several times the legal defense ability of using the dial indicator to verify the .001 to .005 movement of the hub after re installing it.

Harder to quantify preload.  Easy to be off.  Any failure would be a lawsuit.

Looks like to me they leave the bearings slightly loose to be able to fend off suits versus take the play out of a tapered roller bearing an unverifiable amount.

My long term chassis Foretravel dealer mechanic preloaded mine a bit. 

An experience and feel thing.

Watch the video and see what you think as to why?

My old Honda bike had a initial torque in the steering head bearings to align the roller pins then back off and retorque at 22 pound feet in the manual.

If no one has any wander at the .001-.005 that's great.  Just need the feedback.

Not loose.  Read between the lines on this maybe.
"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: Front wheel seal replacement on my 99 U270

Reply #27 –
Quote from: wolfe10 –
I have a lot of trouble believing that the correct end-play will affect wander.  We are talking about .001- .005". Can not understand wanting to go from .001" to zero or pre-load. 

Neither bearing nor axle manufacturers recommend this (if they do, please post link).

My 100k coach wandered and had a dead spot in it.  Unknown the play at that time in the bearings.

Re tightened the play and wander and dead spot were gone.

Wear?  Poor initial bearing adjustment when new? No idea

When I questioned my 30 year chassis mechanic his answer was he preloads the bearing a bit to take any wander out of the coach.  Period.

No call backs for him? Happier customer?
"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: Front wheel seal replacement on my 99 U270

Reply #28 –
Bob,
Agree with the .001-.005 adjustment on taper wheel bearings, my question is your mentioning the preloading of the bearings then adding a torque ft lb number.
The reason for the Free .001-.005 is for lube ability of bearings, with zero clearance, lube is an issue.
Also, wheel bearings loose enough to cause a driving issue would be detected by most fools early on.
Also slightly loose taper bearings last a lot longer than ones that are "Preloaded", zero clearance

Re: Front wheel seal replacement on my 99 U270

Reply #29 –
Quote from: wolfe10 –
I have a lot of trouble believing that the correct end-play will affect wander.  We are talking about .001- .005". Can not understand wanting to go from .001" to zero or pre-load. 

Neither bearing nor axle manufacturers recommend this (if they do, please post link).
1 to 5 mils can be a lot...especially with a 22.5 inch rim + tire there to amplify the play.


And here's the link--I'd say Timken knows what they are talking about....and I've posted this before: Timken knows more than all of us, so see what they say about preload (if preloading took away oil clearance, why would they say it's acceptable?): http://www.pirate4x4.com/tech/billavista/PDFs/Timkin%20bearing%20pre-load.pdf

Topic where I posted this: front wheel bearing preload?

Edit: NSK also has a PDF on preloading: http://www.nskamericas.com/cps/rde/xbcr/na_en/Preload.pdf

Preloading bearings is common practice.
1998 U270 34'

Re: Front wheel seal replacement on my 99 U270

Reply #30 –
Krush,

From your first link (see below) it appears that the bearings/wheel end design should be designed for preloading.

I do not have any information on using this technique on the OE Foretravel bearings/wheel ends. 

Always interested in learning something new.

So, do you want preload in your wheel bearings?
It depends on the wheel end design and the
quality of the components used. If the
traditional design is your preferred wheel end, be
careful to avoid excessive preload, the risks are
serious. However, new wheel end designs
utilizing Timken quality components create
opportunities to safely use slight preload,
reduce maintenance costs and improve fleet
profitability.
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: Front wheel seal replacement on my 99 U270

Reply #31 –
You can read the text and interpret as you wish. They state be careful to avoid "excessive" preload--probably added by the lawyers. But lets quote the rest of what it says: "If the traditional design is your preferred wheel end, be careful to avoid excessive preload". AND: "To date, there isn't anything available that will confirm that the fastener is providing the correct preload setting. Be aware that if you are attempting to set preload in a traditional wheel end, you are depending on the quality of all the components and the skill of the technician to get it correct every time. "

Is this not what I've been stating the entire time? There is no idiot-proof procedure to measure preload with standard bearings....it takes skill. However, requiring SKILL to preload is much different than saying, "preloading a bearing will cause it to fail. Don't preload, it's dangerous, etc etc." Open heart surgery requires great skill too, but that doesn't mean it isn't done correctly every day.

The other article link I gave is regarding bearing preload as well, and is not specific to wheel bearings.

We all can do as we wish, but wheel bearings are not some super-special fancy magic hunk of metal that the normal design practice of standard roller bearings can't be applied to.

The fact is that wheel bearings live a pretty easy life in not too difficult conditions.
1998 U270 34'