Chiming in late here - I've found the CVs to get noisy when under heavier load and also after driving a while. 

Driving home from Las Vegas, I got into Kingman late at night (driving around 35 mph and occasionally stopping to let the joints cool) and was able to "rent" a grease gun with a needle tip from a mechanic at a TA truck stop. Joints were quiet the rest of the way into Phoenix. No visible damage done!

Karl Wolz
Sent from my electronic umbilicus

> On Oct 4, 2014, at 6:26 PM, Dave Mcneely <mcneely4@COX.NET> wrote:
> 
> Thanks Mark.  Rich has concurred also.  So I'll check the joints.  mcneely
> 
> ---- mark drillock <mdrillock@COX.NET> wrote:
>> Yes, the CV joints would be under maximum stress when you were climbing.
>> The extra effort by the engine that triggered the high speed fan was put
>> through the axles to the rear wheels.
>> 
>> Mark
>> 
>> Dave Mcneely wrote:
>>> Mark, thanks.  Would the CV joint/axle be more likely to knock under the conditions I experienced?  I was prepared to think it was an engine knock simply because of the conditions.  The knock did not recur at other times, and then reappeared when I climbed another steep grade.  I'll have everything checked when I get settled in at Spokane.  Meanwhile, I won't be driving the beast all that much, anyway.  As DeanB suggested, I'll switch to a synthetic oil, too.  After all, for one or two oil changes a year, the cost is trivial compared to tearing up an engine. If it makes a difference, it is cheap insurance.  mcneely
> 
> --
> David McNeely