I'm sure a welding shop could fabricate a shield to protect the plumbing. I'd stay off such rocky roads that would require them, you'd probably shake something else loose on a road so rugged that something would hit the drains.
The other strategy could be to use the type of twist lock fittings that join the slinky together to make the drains removable. That would keep them from being damaged by the tire alligators you might encounter on the highway.
__________________
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI
|