Ken Powell wrote:

 If we could do a survey, I bet we would not find ANY unmodified Ross
 boxes  with 500 hrs. at 130 HP average output.  I know that there is
 not any way to prove this, so you are right in that only time will
 tell for sure and we have only heard of a couple of failures - I
 wonder how many failures Ross knows about?  Ross's system might work
 fine in low HP applications, but ...  We do know that Ford designed
 the gears to have internal lubrication, which Tracy implemented and
 Ross did not implement.  Ford would not have incurred the
 manufacturing overhead for this if they had not felt that it was
 required for durability.  We do seem to hear about a lot of boxes
 that have gone back to Ross for rework - why?  I'm not trying to be
 difficult; I do believe that this box has a potential for major
 problems based on input from the members of this newsletter.

 Ken Powell

Jerry Hey wrote:

O.K.  Are there proven modifications?  Who is doing them?  Or should
I scrap the  Ross?

Not really. Art Luther is in the process of making some changes now.

I definitely would not scrap it. Do you need it right now? As time goes
on and people get more hours we will know more about what modifications
work. Also Ross gear boxes vary from unit to unit. Some work better than
others. It is therefore impossible to generalize about them except when it comes
to the need for a sun gear thrust bearing. It is best to put in a sun gear 
thrust bearing and see how it works in your application. Then fix it if 
necessary as they don't seem to fail catastrophically. 

OTH if you are bound and determined to scrap it, send it to me and I will
take it apart, photograph the parts, measure it and suggest and draw up 
some design changes for the thrust bearing and perhaps better gear oiling.

Paul Lamar
 
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