I took my first long road trip in the car last week. I have used it to go 350mi one way several times, but never an extended family trip. Car is 1 year old. Duramax LT Sig with max tow.
Trip was Seattle > Oregon > Idaho > Utah > Las Vegas - Nevada > Idaho > Orgon> Seattle
Overall 2650mi, got 26MPG total, which included 3 days city driving in Las Vegas. Used a bit less than 1/2 tank of DEF on the trip.
Initially I was a bit disappointed in the mileage, since I have gotten 28-30 on previous road trips. However, I was loaded with 5 adult-sized people and about ~500lbs of luggage, and this was nearly all mountainous driving. Also, and perhaps significantly, the speed limit in Idaho and Utah is 80mph, and Nevada I was doing ~75 regularly on deserted two lane roads. So Overall I think not too bad considering city driving and the speed I was doing (>75mph) for 80-90% of the highway miles. Hoping the recent computer update they did (one day before leaving) didn't affect my future mileage.
The only minor hitch/scare, was on the way out of Las Vegas. It is a steady elevation gain for a few hours, and at a small town about 2 hours into that leg I stopped for gas (Ash Springs NV), just to get a bit so I knew I would have enough to reach the final stop for the day (Twin Falls ID). Pulling out of the gas station, I looked down to notice the high temp light illuminated in red on the dash. The lower temp gauge was fine though. No steam, no leaks. Pulled over, got out the manual, and read this can happen after a long ascent and stopping. Then I remembered a Quora feed I got in one of my trash mail accounts recently, that asked: "Should you let your engine run after a long drive before shutting down?" The answer was sometimes, and though I cannot remember the details, I think it specifically mentioned diesel engines, and that the engine can overheat after stopping, since there is no cooling going on after shutting down, and thus they can continue to heat up for a bit. Makes sense, though I don't know that I'll remember to let it run in the future. Anyway, started back up after 5-10 min, and the indicator was off, car ran fine.
Overall, the diesel Suburban is an absolutely fantastic family road trip vehicle.
Trip was Seattle > Oregon > Idaho > Utah > Las Vegas - Nevada > Idaho > Orgon> Seattle
Overall 2650mi, got 26MPG total, which included 3 days city driving in Las Vegas. Used a bit less than 1/2 tank of DEF on the trip.
Initially I was a bit disappointed in the mileage, since I have gotten 28-30 on previous road trips. However, I was loaded with 5 adult-sized people and about ~500lbs of luggage, and this was nearly all mountainous driving. Also, and perhaps significantly, the speed limit in Idaho and Utah is 80mph, and Nevada I was doing ~75 regularly on deserted two lane roads. So Overall I think not too bad considering city driving and the speed I was doing (>75mph) for 80-90% of the highway miles. Hoping the recent computer update they did (one day before leaving) didn't affect my future mileage.
The only minor hitch/scare, was on the way out of Las Vegas. It is a steady elevation gain for a few hours, and at a small town about 2 hours into that leg I stopped for gas (Ash Springs NV), just to get a bit so I knew I would have enough to reach the final stop for the day (Twin Falls ID). Pulling out of the gas station, I looked down to notice the high temp light illuminated in red on the dash. The lower temp gauge was fine though. No steam, no leaks. Pulled over, got out the manual, and read this can happen after a long ascent and stopping. Then I remembered a Quora feed I got in one of my trash mail accounts recently, that asked: "Should you let your engine run after a long drive before shutting down?" The answer was sometimes, and though I cannot remember the details, I think it specifically mentioned diesel engines, and that the engine can overheat after stopping, since there is no cooling going on after shutting down, and thus they can continue to heat up for a bit. Makes sense, though I don't know that I'll remember to let it run in the future. Anyway, started back up after 5-10 min, and the indicator was off, car ran fine.
Overall, the diesel Suburban is an absolutely fantastic family road trip vehicle.
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