Wow!  They only last 6 years average?  Must be low end parts.  I know
for the years I worked as a Nissan tech the only time we had any
problems with the OEM parts was when the owners didn't change their
filters reularly and the filter media failed and let the junk through.

Now hoses and seals, that was something else.  Again the owners would
run various `magical' off the shelf cleaners through and wonder why
the hoses were ate out from the inside.  LOL  That's what ended up
leading to the voluntary recall on the Maxima's, Z's and a few others
for a certain time period to replace the hoses, filter and fuel rail
assemblys.  I was the `lucky one' that got to do those almost daily
for the last 2 years of my work.  Lucky is an operative word there.
;-)  The hose that ran from the bottom of the filter to the tank line
on the Maxima's was a P-A-I-N!  But hey, it was all free.  :-)

Wil