I have 3/4 ton with the 6.5 TD. Although I've had to do quite a bit of repair work to it (A/C compressor and coils, turbo waste gate, engine & tranny mounts, fuel lines, oil lines, harmonic balancer and a few others) I'd say it's mostly because the truck is old and has over 200,000 miles on it. Engine runs like a top, absolutely no blowby and the tranny is rock solid. I've made several trips from TX to TN, driven it from PA to TX, pretty much all over the place. Most comfortable highway cruiser hands down. Had to change the final gears to 3.73 from 4.10 for better mileage. Now I get a whopping 17-19ish mpg on the highway at 65.
the full review
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