Re: Warn hub munching.

["Owen Minor" <renarac@domain.elided>]

I knew exactly what you guys were talking about.

The flange that the wheel hub (not the locking mechanism, but the HUB that
carries the bearing races) mounts to on a Warn conversion is not designed to
take load in the direction that the conversion applies to it. In stock form,
this flange only carries the backing plate and some pull/compression force
along the line of the axle.

By attaching a hub to this flange you get all force acting with twisting
force on the flange about the same axis as the pinion shaft.
It can't be the housing anywhere from the location of the original bearing
race inward, because, at least, there is 90% of the force working on the
housing. Detroit didn't design with 10% failure margins during the time the
Dana 44 was designed. More like 50% minimum. Double margin is a good rule of
thumb on most stuff.

A non-floating axle doesn't work as a "truss". It carries the load as a
shear point right next to the wheel bearing. Any force translated to the
carrier is incidental and only aligns the axle.


-- Original Message -----
From: Tom Mandera <tsm1@domain.elided>
To: Daniel Nees <cookiedan@domain.elided>
Cc: Owen Minor <renarac@domain.elided>; <ihc@domain.elided>
Sent: Thursday, June 24, 1999 2:11 PM
Subject: Re: Warn hub munching.


> Daniel Nees wrote:
> >
> >    Tom is refering to the REAR axle full floater kit. The rear hubs on
>
> Right you are, Dan!
>
> With a centered rear diff.  In a semi-float (which, FAIK, was never a
> FRONT axle issue) the axle shafts bear part of the weight.  The only way
> for them to "share" this weight with the truck, is by applying pressure
> to the differential (side gears).  You have one bearing at the flange
> end, and a tire "outside" of that.  Granted, it's a short lever on the
> tire side, and a long on "inboard" at the diff, but it's still there.
>
> I'm theorizing that a full-floater by design has a stronger/thicker axle
> housing *TUBE* to support the weight.  When you convert a semi-float,
> the housing doesn't have this extra thickness, and the axle shafts are
> bearing no weight, so it flexes and causes the hub damage Dan mentioned.
>
> Truss it, and you're in business.
>
> I was reminded of this by a Jeeper.. that runs 36s or something bigger
> on his Dana 30.  Claims he hasn't broken anything since he trussed it
> (broke stuff left n' right before)
>
> He thinks that the truss keeps the Dana 30 housing from flexing which
> keeps other stuff from breaking.
>
> Still doesn't mean I'm dumping my '44 for a '30 tho. ;-)
>
> -Tom "gotta replace another front U-joint still" Mandera
>