Are you using 'auto' or 'manual' leveling?
I've noticed 'auto' tend to raise the MH higher at times...
When parking at home where I know the driveway is level side to side - I manually drop the front jacks just enough to get level (and only do that when I'm going to run the fridge - as it is very finicky compared to my last RV.)
If you only have a slight slope - I'd expect this to level without raising the wheels off ground.
Otherwise if you don't want the front wheels off the ground - you would need blocks/ramps under the wheels first - not just under the jack pads.
Blocks under the jack pads just change how far the jacks need to extend - won't change the final height of the wheels.
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