Running in new wheel bearings?

[Ext User(Diesel Damo)]

Next weekend I'll be getting new wheel bearings all round, along with
the work on the diffs (engine rebuild has been pushed back to December
BTW). I vaguely recall hearing once that with new wheel bearings you
should "take it easy on them at first".

How exactly should one "take it easy" on them? Is there a speed I
should stay below? If so, for how long?

The work is being done in Canberra so it's a 200km trip home once I
pick it up. Going in that direction, it will also involve the worst our
road has to offer; serious corrugations and LARGE pot holes.

The rough bits will only start once I'm 30km from home, so there'll be
about 170km of fairly decent sealed roads before that.

Also, are there any considerations to take into account with new
limited-slip diffs? Do they need some sort of "running in" too?

[Ext User(OzOne)]

Just drive it!


On 26 Aug 2005 23:24:44 -0700, "Diesel Damo" <Diesel_4WD@yahoo.com.au>
scribbled thusly:

>Next weekend I'll be getting new wheel bearings all round, along with
>the work on the diffs (engine rebuild has been pushed back to December
>BTW). I vaguely recall hearing once that with new wheel bearings you
>should "take it easy on them at first".
>
>How exactly should one "take it easy" on them? Is there a speed I
>should stay below? If so, for how long?
>
>The work is being done in Canberra so it's a 200km trip home once I
>pick it up. Going in that direction, it will also involve the worst our
>road has to offer; serious corrugations and LARGE pot holes.
>
>The rough bits will only start once I'm 30km from home, so there'll be
>about 170km of fairly decent sealed roads before that.
>
>Also, are there any considerations to take into account with new
>limited-slip diffs? Do they need some sort of "running in" too?



Oz1...of the 3 twins.

I welcome you to crackerbox palace,We've been expecting you.

[Ext User(JD)]

Diesel Damo wrote:

> Next weekend I'll be getting new wheel bearings all round, along with
> the work on the diffs (engine rebuild has been pushed back to December
> BTW). I vaguely recall hearing once that with new wheel bearings you
> should "take it easy on them at first".
>
> How exactly should one "take it easy" on them? Is there a speed I
> should stay below? If so, for how long?
>
> The work is being done in Canberra so it's a 200km trip home once I
> pick it up. Going in that direction, it will also involve the worst our
> road has to offer; serious corrugations and LARGE pot holes.
>
> The rough bits will only start once I'm 30km from home, so there'll be
> about 170km of fairly decent sealed roads before that.
>
> Also, are there any considerations to take into account with new
> limited-slip diffs? Do they need some sort of "running in" too?

None of the work you outline should require any running in, but check
temperature of bearings after, say, 20-30km to pick up any faulty work, and
again after perhaps 100km. Hubs should be barely warm this time of year,
(unless you've been using the brakes heavily) and should all be the same
temperature to feel.
There should be no issues with the diffs. All the bits you are talking about
have ball or roller bearings and these do not need any wearing in. The only
bit that has significant sliding contact is the crown wheel and pinion, and
these should have been manufactured to match very accurately, and the EP
oil is designed to prevent wear from high pressure sliding contact between
the teeth anyway.
JD
JD

[Ext User(John_H)]

Diesel Damo wrote:

>Next weekend I'll be getting new wheel bearings all round, along with
>the work on the diffs (engine rebuild has been pushed back to December
>BTW). I vaguely recall hearing once that with new wheel bearings you
>should "take it easy on them at first".
>
>How exactly should one "take it easy" on them? Is there a speed I
>should stay below? If so, for how long?

If it's done by a competent mechanic there's no special treatment
required... but beware of excessive pre-loads. Checking the hub
temperatures after you've travelled a few km should give a good
indication (if they're running hot you've got a problem).

Patrols in particular (which are more difficult to set up than
Toyotas), are invariably stuffed by their dealer mechanics (who're
rarely competent). Front bearing failures after they've been worked
on are a common occurrence -- in spite of their consistently achieving
200,000 km from new without human intervention.

--
John H

[Ext User(Clockmeister)]

"John_H" <john4271@hotmail.com> wrote in message
news:9g80h1h57u6aq9devasq6o56k764otj8el@4ax.com...
> Diesel Damo wrote:
>
> >Next weekend I'll be getting new wheel bearings all round, along with
> >the work on the diffs (engine rebuild has been pushed back to December
> >BTW). I vaguely recall hearing once that with new wheel bearings you
> >should "take it easy on them at first".
> >
> >How exactly should one "take it easy" on them? Is there a speed I
> >should stay below? If so, for how long?
>
> If it's done by a competent mechanic there's no special treatment
> required... but beware of excessive pre-loads. Checking the hub
> temperatures after you've travelled a few km should give a good
> indication (if they're running hot you've got a problem).
>
> Patrols in particular (which are more difficult to set up than
> Toyotas), are invariably stuffed by their dealer mechanics (who're
> rarely competent).

On the contrary, but it's not the mechanics who get to do the wheel
bearings.

Front bearing failures after they've been worked
> on are a common occurrence -- in spite of their consistently achieving
> 200,000 km from new without human intervention.
>

It isn't brain surgery. We've done thousands over the years and have never
had a problem with them.