[DeTomaso] Rollers or Balls?

[JDeRyke at aol.com]

In a message dated 4/22/12 9:46:09 PM, fisher95020 at yahoo.com writes:

> I'm interested in folks opinions on the merits of changing out the balls 
> for roller bearings. Ideally,  I'd like data on long term roller bearing 
> longevity, but failing that, I'm interested in opinions, and experiences.
> 
David, I was also curious early on in our ownership. So I got a spare rear 
carrier and altered it for tapered roller bearings, using my own design. I 
installed the rollerized upright on our car on one side only as a direct 
comparison. I documented the build with dwgs etc in the Aug '99 POCA Newsletter. 
THe car has gone some 70,000 miles in the subsequent 12 years, with 
absolutely no difference between the stock setup on one side and the tapered roller 
setup on the other. Matter of fact, I often forget which is which until I 
look at them with a rear wheel off. Note- the ball bearing side got a welded 
stock axle to properly fit the ball bearings to the axle- something many 
Panteras did not get as stock. If the press fit is too loose, the ball 
bearing(s) will tear up the softer axle, resulting in wobble. Tapered roller bearing 
conversions really don't need a press-fit axle, but all the commercial 
conversions install a billet axle anyway.

> 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??
> 
Probably not. The inner bearing is only locaed in the carrier by the 
spacer, so a shorter spacer does no harm. Some Pantera mechanics face the spacer 
ends in a lathe whenever the assembly is taken apart.
> 
> 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?
> 
Uneven rear tire wear in the rear is common for a whole range of reasons, 
especially with super-wide tires. The rear suspension tends to collapse 
inward at the top, giving 2-3X more camber than is desirable. The stock bay-brace 
does not hold the upper part of the rear suspension firmly, and most 
aftermarket aluminum braces are identical in design so are similarly useless 
structurally. The black steel Hall brace has much longer ends that fit tightly in 
the welded pockets attached to the inner fenders, and DOES work well to 
brace the suspension. There are other structural bad-news things that accompany 
super wide rear wheels & tires besides uneven tire wear.
Good luck- J Deryke