I had an '04 350 that I got to 175k+ miles, at that point it blew the engine oil cooler--$2700--fixed that and traded for an '07 with no problems at 12.5k.
For some help on the boot problem, you might check on
www.thedieselstop.com website. There were quite a few that had that problem. Another helpful Ford site is
www.fordtruckenthusiasts.com
or
www.fte.com
The '04 was SRW and only pulled the MS about 1200 miles, but no trouble pulling it. My DRW '07 is doing just fine, so far, when towing.