Depends on how many times it gets operated when in an 'unlevel' situation.
Those quick stops along side on ramps, those short rest stop situations where rig is a bit off level, those overnight stops that it's kinda level but not really etc.
20 minutes of -off level- operation can cause overheating issues with coolant due to disruption of gravity flow. The sodium chromate (anti-rust inhibitor) can crystallize due to the overheating......then it plates out on inside of tubing like a plaque. Damage is accumulative and permanent.
Turning fridge On/Off or leaving running has little affect.....thermal stresses are not significant ------fridge heat source cycles on/off all the time
Overheating/disruption of gravity flow is major source of failures.
No 'moving parts' so nothing to wear out.....
Keep it 'comfortably level' for longevity
Is it time for your medication or mine?
2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31