I just took a hy35 off at around 268,000 miles. Truck was stock for the first 250,000 miles. Injectors and some sort of box the last 20,000. Turbo feels as tight as a stock one. I'm thinking with good oil change and not to much abuse it could be longer than the motor. You actually are suppose to have no metal to metal, good clean oil ought to keep any wear out of it.
My hx 35-40 probably has 125,000 miles on it in three different trucks. I don't see any signs of wear in it. I am meticulous about oil changes so that may have something to do with it.
Mines still spooling just fine with 411hp to the wheels. It has 182,262 miles on it. Granted it has a good amount of play up and down and you can see where the blades have scraped the housing just a little over time. Its had the chip and all for 60-80k miles. Ive run the dog crap out of it though. Im trying to get all I can possibly get out of mine though. That may sound stupid but Ive seen quite a few go out and not hurt the engine internally.
Diesel Bombers ® - All Content Protected Under Intellectual Property Rights Law of Registered Trademarks Reg. No. 3,494,401 Cls. 100, 101 & 104 Under Int. Cl. 38
USE AT YOUR OWN RISK WE HOLD NO LIABILITY FOR ANY CONTENT RIGHT, WRONG OR INDIFFERENT