From: "Tony Ingenoso" 

Why would this occur at a greater incidence than above ground vehicles?
Boots/seals routinely last for many years above ground in much greater
heat.

Silicones last for the life of the vehicle in fact unless physically torn.

"Robert Comer"  wrote in message
news:42ddc471$1{at}w3.nls.net...
> Any of these rubber or plastic boots are going to dry and crack when
buried
> in sand...
>
> - Bob Comer
>
>
> "Tony Ingenoso"  wrote in message
> news:42dd9d6a$2{at}w3.nls.net...
> > Via what mechanical mechanism does sand accomplish this magical
> > penetration
> > of sealed units?

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