[DeTomaso] Rollers or Balls?

[MikeLDrew at aol.com]

In a message dated 4/22/12 21 46 8, fisher95020 at yahoo.com writes:


> I'm replacing my rear axle bearings while I renew all the suspension 
> bushings
> and have noticed some previous discussions on roller bearing conversions 
> for the
> rear axles.
> 
> I'm interested in folks opinions on the merits of changing out the balls 
> for
> roller bearings. 
> 
>>>Tapered roller bearings, you mean...just to be clear.   Ball bearings, 
needle bearings, etc. are all different forms of roller bearings.   The 
Pantera modification consists of replacing the standard ball bearings with 
tapered rollers.

> >Ideally,  I'd like data on long term roller bearing longevity,
> but failing that, I'm interested in opinions, and experiences.
> 
>>>When I first started playing the Pantera game, Dennis Quella's tapered 
roller bearing conversion was widely acknowledged as being The Hot Setup, and 
since I had to have The Hot Setup for everything, I made the move.   It has 
since served me quite well.

But I've also learned that ball bearings with proper axles work just as 
well for a fraction of the cost.   While I've been quite pleased with the 
performance of my setup, if I had to do it all over again, I probably wouldn't.
> 
> >On my car,  I noticed the outside bearings are rough and the inside ones
> (larger) are still smooth.   Curiously,  one side of my car has a shorter 
> spacer
> between bearings than the other side, although both carriers seem to be
> identical.   I suspect someone changed a bad bearing and put the wrong 
> spacer
> in??
> 
>>>Either that, or they were trying to compensate for axle wear by simply 
shortening the spacer and letting the new bearing wear on a different part of 
the axle.   While the outer bearing location is completely fixed, the inner 
bearing can 'float' along a reasonably wide range within the hub carrier.
> 
> >Lastly,  I'm running 335/17s on the rear, which I suspect are less than 
> ideal
> for handling, but who can resist the bada** 70's look they impart?   I 
> just
> changed rear rubber and noticed that the inside of the tires have worn 
> down a
> fair bit faster than the outsides.  I am contemplating compensating with 
> camber,
> but I suspect there may be enough flex in the rims, suspension and frame 
> that I
> might just have to live with the tires wearing uneven.  Any thoughts?
> 
>>>You never have to live with anything undesirable.   Ideally you should 
have close to zero negative camber (particularly with those wide tires--zero 
is the goal).   When new, the Pantera chassis might have been able to 
provide that, but over time, some cars have 'settled' and even with all the shims 
removed from the lower A-arms, there is still excessive negative camber.   
Some Pantera vendors sell enormously expensive adjustable upper A-arms to 
compensate, but this is completely unnecessary.   Instead, if you have 
excessive camber that you can't get rid of via traditional means, you can just get 
fixed-length, longer upper A-arms.   This will then afford you the means to 
adjust the camber by the conventional method, using shims between the lower 
A-arm mounts and the chassis.

Hall and Byars both sell the fixed-length A-arms.   I wouldn't buy them 
until you demonstrated to yourself conclusively that they were necessary, but 
if they were, I wouldn't hesitate to buy them.

And as for the axles/bearings, I'm a big fan of the almost-no-cost 
modification of replacing the standard single-row inner bearing with a double-row 
bearing.   It has almost twice as much surface area acting on the axle, and 
thus greatly reduced loading; the only thing necessary to install them is to 
shorten the spacer by the additional thickness of the double vs. single 
bearing.

I can send you a PDF article on the subject if you like....

Cheers!

Mike