Sarah Palin has no love for the daddy of her grandson ... because she just barked out to TMZ that Levi Johnston is a 'deadbeat dad.'
As TMZ previously reported, Levi just filed legal docs asking for 50/50 joint custody of 4-year-old Tripp. He says it's in the boy's best interest.
As for whether Levi should get joint custody ... Palin is incredulous.
But here's the rub ... Levi is roughly $66k behind in child support.
Palin's disdain for Levi is palpable. Watch the video ... you'll see.