I was well pleased overall with the performance of the GMC on the first long trip in our Sequoia, from Raleigh to Harrisburg, PA and then to Oshkosh for the airshow. Came home 10 days later on a more direct route: via Indianapolis, Dayton, Charleston WV, Beckley, WV.
The total drive time was around 36 hours and maybe 2300 miles. The fuel economy ran about 8.5 - 8.8 mpg. I tried to run non-ethanol most of the way, using the Pure Gas app to locate stations, but had to fill with premium unleaded a couple of times.
Most of the way I drove State and US highways when able, and generally at 45-55 mph. At those speeds, my rig runs great and drives effortlessly. Smooth and quiet. So enjoyed a lot of small towns and cornfield-lined byways across WI, IL, IN and OH. It also ran the interstate easy at 62-70 at 2100-2200 RPMs. When the big trucks blow by, tends to move me sideways.
Going over the mountains, on the longest pulls uphill, the coolant temp climbed to around 230°, but was otherwise just perfect during all other times. It would cool off quickly and I just stopped for a bit whenever it was too hot. I experimented with dropping down into the S gear on the longest grades, which resulted in about 2900-3000 RPMs and caused more rapid coolant heating. The oil temps were fine.
I have a small seep from the right side valve cover. I think this contributed to it using about a quart of oil per 10-12 hours of drive time.
The living systems were good. The Black Tank monitor being INOP was just a minor issue. We learned that 3 days was the max between needing to dump. I simply stopped whenever the opportunity presented itself to dump and having the macerator makes it so easy. Love’s Truck Stops, some Rest Areas and the campgrounds provided plenty of opportunities to keep it empty, which also eliminated any fumes building up.
Enroute repairs were needing to re-wire the under-dash AC blower motor switch, which had stopped working. I got a new switch from Amazon and was glad to have fixed this. The old one looked charred and was hot. It was falling apart.
I also proactively replaced the carb fuel filter, so had no issues with it bogging down. I chose to do this while the engine was cold - the last time I had to do it on the side of the road with a hot-ass engine. The filter had a lot of rust particles, so I know I need to tend to dropping the tanks and cleaning/sealing them to stop the problem.
The shower and bathroom worked great, learned a good way to manage showering. I cooked one meal on the range to try out the gas burners and that was easy.
The Onan troll worked great, never failed to start up and kept us cool at every stop. We worked really hard on it, so I am very happy to have it become dependable.
So a success. I have my short list of mechanicals to improve: black tank, fuel tanks, heavier duty brake booster.
I got a lot of good experience with it in various conditions. I could pretty much live in it. Gratifying after such a long two years of working on it to feel it is reliable and useful.
By the way, we stayed at the Seaplane Base at Oshkosh. Here are a few pix:
The total drive time was around 36 hours and maybe 2300 miles. The fuel economy ran about 8.5 - 8.8 mpg. I tried to run non-ethanol most of the way, using the Pure Gas app to locate stations, but had to fill with premium unleaded a couple of times.
Most of the way I drove State and US highways when able, and generally at 45-55 mph. At those speeds, my rig runs great and drives effortlessly. Smooth and quiet. So enjoyed a lot of small towns and cornfield-lined byways across WI, IL, IN and OH. It also ran the interstate easy at 62-70 at 2100-2200 RPMs. When the big trucks blow by, tends to move me sideways.
Going over the mountains, on the longest pulls uphill, the coolant temp climbed to around 230°, but was otherwise just perfect during all other times. It would cool off quickly and I just stopped for a bit whenever it was too hot. I experimented with dropping down into the S gear on the longest grades, which resulted in about 2900-3000 RPMs and caused more rapid coolant heating. The oil temps were fine.
I have a small seep from the right side valve cover. I think this contributed to it using about a quart of oil per 10-12 hours of drive time.
The living systems were good. The Black Tank monitor being INOP was just a minor issue. We learned that 3 days was the max between needing to dump. I simply stopped whenever the opportunity presented itself to dump and having the macerator makes it so easy. Love’s Truck Stops, some Rest Areas and the campgrounds provided plenty of opportunities to keep it empty, which also eliminated any fumes building up.
Enroute repairs were needing to re-wire the under-dash AC blower motor switch, which had stopped working. I got a new switch from Amazon and was glad to have fixed this. The old one looked charred and was hot. It was falling apart.
I also proactively replaced the carb fuel filter, so had no issues with it bogging down. I chose to do this while the engine was cold - the last time I had to do it on the side of the road with a hot-ass engine. The filter had a lot of rust particles, so I know I need to tend to dropping the tanks and cleaning/sealing them to stop the problem.
The shower and bathroom worked great, learned a good way to manage showering. I cooked one meal on the range to try out the gas burners and that was easy.
The Onan troll worked great, never failed to start up and kept us cool at every stop. We worked really hard on it, so I am very happy to have it become dependable.
So a success. I have my short list of mechanicals to improve: black tank, fuel tanks, heavier duty brake booster.
I got a lot of good experience with it in various conditions. I could pretty much live in it. Gratifying after such a long two years of working on it to feel it is reliable and useful.
By the way, we stayed at the Seaplane Base at Oshkosh. Here are a few pix:
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