I can’t believe in this day, they would still be using timing belts. And in the back of the engine of all places. This makes about as much sense as Ford with their stupid internal water pump design on the ecoboost. I suppose they don’t care who they piss of by doing it this way since it’s usually the third owner by the time the repair bill comes in.Please do not buy a modern diesel, especially in a small truck that doesn't need it. ESPECIALLY if you plan to keep it. There is ZERO problems with the V6 in the modern Colorado/Canyon nor is there any issues with the 8 speed transmission. 3.6L problems were back in 07-10. It's a good engine now. The 8-speed problems were very minor (especially compared to issues with the 6L) with the early ones having converter/fluid problems and fluid temp sensor issues.
BTW, when that engine does need the timing belt replaced, the transmission has to come out because it's on the back of the engine. Please make sure a smaller truck is what you want. You'll pay slightly less for a truck that will be nearly worthless in 6-9 years versus a full size truck that will retain value well. Not much market for a small truck up here so for new sales the full size outsells the mid by probably 20:1 new.
But yeah, the time for small diesels passed about 10-15 years ago when they started with the exhaust scrubbing equipment. The up charge up front plus the high price fuel, def and eventual repair bills make these a nonstarter for me. I really think I’d come out better with total cost of ownership going with a 3/4 ton gasser than a new small diesel.