Will Onan Cummins Diesel Generator CM94RR Work At 8,500 Elevation In Colorado?
Updated 08/15/2025 | Published 07/16/2025
Question:
We spend our summers in southwest Colorado and often boondock above 8,000 feet. Our current generator gets grumpy in the thin air. Will this one handle the elevation? 2019 Newmar Canyon Star 3927 Toy Hauler
asked by: Mark A
Expert Reply:
Absolutely, Mark and Wendy.
The Onan 6000 watt generator # CM94RR is an onboard diesel unit with a 3-cylinder liquid-cooled engine that’s designed to auto-adjust for elevation. It performs much better at high altitudes than most gas generators, especially when paired with a load-sensing inverter-charger. At 8,500 ft you won’t see a major difference in performance, and no rejetting is needed.
Just add a winter diesel additive if you’re up there during cold snaps. We’ve seen rigs run this generator at 10,000 ft in Colorado with no issues.
As a side note, you may be able to get a high elevation jet kit for your generator if you let me know what you have.
Product Page this Question was Asked From
Onan Generator - Quiet Series Onboard RV Generator - 6,000 Watts - Diesel
- Generators
- No Inverter
- Diesel
- 4001 Watts or More
- Onboard Generator
- 12V Output
- Carbureted
- Electric Start
- Cummins Onan
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Andrew N.
8/15/2025
Hey Mark and Wendy, did you get a chance to try out the Onan 6000 watt generator at high altitudes? I'm curious to know how it performed for you, especially since it’s designed for those conditions. Let me know how it went, as it could really help others who camp in similar spots!