Yugoslavia broke off its relations with the USSR in June 1948 (see: Informbiro). Yugoslavia had never, ever, been a Soviet satellite.
Tito's refusal(s) to submit to Stalin were the reason the Yugoslav Communist Party was kicked out of the Cominform, and some historians argue that, had Yugoslavia bordered the USSR, Stalin would've intervened militarily.
Tito dealt with the Stalinists in Yugoslavia by sending them to Goli Otok ("Barren Island").
My apologies - I was mistaking the USSR invasion of Hungary and Czech for Yugoslavia. Those crazy Slavs! /joke
Yugoslavia, while Communist, did keep themselves separate from the USSR. I understand that they still had a significant trade relationship.