There are a couple different ways to service your gennie.
Our gennie drops out the bottom, but we can change oil, oil filter, spark plug and gas filter from the front without moving anything. I wouldn't think routine service would ever require dropping the generator.
You seem to feel its on a slide-out tray. Can you see the tray? Is it bent and that's why it won't slide? You can probably take out some of this theoretical bend with a jack from underneath the tray.
If no tray, look underneath; you should see 4 big bolts (or more) holding the gennie down. On some units, you can loosen the front 2, and the gennie will tilt toward you for access to top and back.
On others, you must loosen all 4, and lower the generator out the bottom (you need to have a hydraulic automotive jack under the gennie to lower it).
Life rocks when your house rolls
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