My V10 has 437,500 as of today, original engine and transmission. My combined weight is typically 22,000 pounds, and over 250,000 of those miles are towing miles.
I did preventatively replace the timing chains, coils, and injectors because I don't want a trip ever side-lined for repairs. Its still starts up strong every morning and doesn't smoke one bit. My transmission is totally un-touched except for adding a magne-fine filter, and a larger cooler (F53s all get the larger cooler stock).
My next van will be a V10 as well, but I don't plan on replacing this one until I pass 500,000 miles. And even then, I'll probably keep it as a spare.
