In the adventure of attempting to stop some coolant seepage, I had the opportunity to peek at the inside of the expansion tank hose where it connects to the turbo coolant line. Although the hose looked dandy from the outside, the inside was a mess of flaking rubber. GAPA shows two listings for the replacement (P/N 3531884); one looks like a Volvo part for $45.66, the other is from Mission Trading Company for $19.12. Anyone have any experience with Mission Trading....the temptation to go with the less expensive hose is almost overwhelming. Any thoughts on replacing the "gray" expansion tank filler cap with the "green" variety while I'm in there? Thanks!!