Steve-O I'm Rooting for Bam ... But Rehab's Just a Start!!!

1/14/2018 12:50 AM PST

EXCLUSIVE

Steve-O[1]'s glad his old friend Bam Margera[2] has checked into rehab, but as an expert on the topic ... he knows Bam's got a long way to go in beating his addiction.

We got a studious-looking Steve-O out grocery shopping in L.A.'s Franklin Village this week and asked him about his former "Jackass" co-star's recent struggles with alcoholism ... and he offered some rather blunt and earnest advice.

The gist -- Bam's got to surrender ... and stick to the steps of sobriety.

Steve-O says he hasn't spoken with Bam in a few months -- so definitely not since his DUI arrest[3] -- but it's clear he's concerned and wishing him the best.

As we reported ... Bam agreed to go to a California rehab facility[4] Friday, and we're told he's committed to getting control of his life for his family.

Steve-O's been sober for nearly a decade after getting clean in 2008 ... so listen up, Bam.

References^ Steve-O (www.tmz.com)^ Bam Margera (www.tmz.com)^ his DUI arrest (www.tmz.com)^ California rehab facility (www.tmz.com)

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