The K-Gro PowerPro is a ridable lawnmower built for K-Mart by MTD and Murray. Released in 1997. Model numbers: 13AL452F120 (38", 12 HP) & 13AQ695H120 (46", 18 HP).
Sounds like a friction clutch/transmission issue, if it reverses fine but says 'nah breh' in drive i'm leaning towards a transmission/transfer case that needs to be opened up or at least shook to see if it jingles like a bell.
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