ONAN 5500 @ high elevations

Team Roper Heeler wrote:
My wife and I will be heading west in September. Overnighting around 9000'. What do I need to address to insure optimum performance. We currently live around 1,500'. Thanks for the help.

Gasoline powered generators do have a carburetor altitude adjustment,,,if you have a gasser....

Effects Of High Altitude And Extreme
Temperatures
If you travel at high altitudes or in extreme temperatures, your generator can lose power. In such lower-density air conditions, you can’t operate as many electrical devices as you could under normal operating conditions.
Power decreases 3.5% for each 1,000 feet above an altitude of 500 feet. For example, to operate at 4,500 feet (4,000 feet above rated generator altitude) multiply 3.5% x 4 (4,000 ft) = 14% power loss. Then multiply .14 x your generator’s power rating: 4,000 watts x .14 = a loss of 560 watts at that altitude.
Power decreases in extreme temperatures by 1% for each 10° F (5.5° C) above 85° F (29.4°C).
NOTE: The carburetor on a non-EFI gasoline generator may require adjustment at high altitudes. (See your Operator’s Manual or your Cummins Onan Authorized RV Service and Parts Dealer.)