The first Chevy Colorado Duramax Tow Test by Fast Lane Trucks who give it a good run down towing a heavy load.
If you do a lot of towing having a diesel makes sense especially if you do over 20,000 miles a year a this will offset the higher servicing cost. Regular servicing of a diesel engine is a must if you want long life and minimal repair bills. Look after a diesel by having oil and filter changes at the recommended mileage and it will repay you many times over. A million plus miles without any motor repair is not uncommon, I have 2 friends who will vouch this. One has a light delivery van, other a SUV both at the million mile mark and both still going strong.
This Colorado is 4WD, engine is 2.8L 181 hp and 369 ft.lbs torque so has a reasonable amount of grunt for heavy work, as shows in this test.
If you are considering diesel you will enjoy this video.
If you are interested in other recent towing reports, here are the links: