After 100k Miles, Plus Towing

[Whizzo]

My 2009 35d just rolled to 107,000 miles, and my extended warranty of course expired at 100k. I have been debating keeping the vehicle for much longer, but it still does so many things well.

I haul a 5000 lb / 2300 kg travel trailer (caravan) since 2012, and have been really impressed with the diesel’s towing performance and towing mileage (approx. 17 MPG). It has the factory hitch and brake controller assembly. I tow an average of 1000 miles per year.

Apart from routine service, in the past seven years the X5 has gone through a battery, a throttle switch, an idler pulley, brake pads, a new DEF heated tank, and a DEF software module reload. I chose to refresh the transmission fluid at 100K miles - after much discussion with my SA, and reading this board - as well as a cooling system flush and fill at 50k and 100k miles.

The SA pulled the intake at 100k, and was surprised that I had practically no carbon build-up. He was surprised, and figures there must be something different about my driving style, as most diesels he sees here in Texas have major CBU issues.

The month, during an especially hard trailer summer towing trip of over 2,000 miles, the “Reduced Engine Power” self-preservation mode kicked in during on particularly steep mountain pull. It reset itself at the next fuel stop, and has not recurred either towing or not towing in three weeks. No codes generated.

The service shop owner says he sees a half dozen X5s with over 150,000 miles on them, and says I should keep this one. What do you think about the lifespan of such an ’09 diesel?