i don't have rancho shocks, but i do recall that rancho used their warranty as a marketing differentiator...but like i said, i got no experience dealing with how well they honor the thing. But it might get you a free replacement set??? If you wanna stay with Rancho, seems to be worth a shot:
Rancho Warranty Details
Oh yeah, even tho it could be said that what we do to our rigs might not qualify as "normal operating conditions" but then again Rancho markets em to us under claims of suitability for wheeling, so there shouldn't be any issue there... <img src="/forums/images/graemlins/cheers.gif" alt="" />
good luck,
/natebear