Concrete Floor Cleaner?

[D45]

Short of using a power washer, what's a good way to get my garage floor clean(er)?

Dirt. Grim. Tire rubber. Needs some tlc but I don't expect miracles

Muriatic acid scares me

Thanks for any and suggestions

 

[FMB4]

Our pre owned 3 stall G floor has every type of stain you can imagine (dirty eng oil, gear oil, rust, and poly U and enamel paint, etc). I coated 2 stalls with latex G floor paint with acceptable results more that 5 years in (could use a re coat at this point). However, I left the single stall 'as is' for various reasons (I'm kinda lazy at my age). Anyway, I've tried a multitude of crete cleaners (both DIY blends and store bought stuff) with disappointing results. Dry sanding with name brand 80 grit wet/dry paper has worked the best with 'Krud Cutter' rust remover/converter being the best for rust stains.

 

[D45]

I wonder about renting an orbital floor scrubber and using a cleaning agent