They had trailed 2-0 and 4-3, but had enough guts and stamina to pull back and overpower Devils with a late surge.
The victory means they are five points clear of second place Cardiff, although the Welsh have four games in hand.
Sheffield had not had a whole lot of success against these opponents over recent times, and this season had been no different; they'd lost all three previous encounters.
And the Welsh served a reminder of that on 10 minutes at the Viola Arena when Belarus international Charles Linglet's wrist shot opened the scoring after a face off, assisted by Stephen Dixon.
Steelers, who hadn't won in Cardiff since March 2018, saw chances fall to Marco Vallerand and Nikolay Lemtyugov on the power play after Sean Bentivoglio was called for interference.
The visitors have potent offensive capabilities, but Brendan Connolly and Jonathan Phillips couldn't get the puck past goalie Ben Bowns.
And the middle period saw an exceptional save from Tomas Duba deny Devils a further goal, Blair Riley the frustrated party.
But with Aaron Brocklehurst sitting out a holding call, Devils were not to be denied, Matt Pope, scoring on the power play, helped by Mike McNamee and Gleason Fournier.
Steelers hit back quickly though, offensive d-man Marek Troncinsky engineering a chance for John Armstrong to backhand away - 2-1 to Cardiff at the half-way point.
With Shaone Morrisonn called out for hooking, Steelers had the chance of equalising and took it, Ben O'Connor finding his defensive partner Troncinsky who whacked in an unstoppable effort.
The momentum swung completely when Michael Davies made it 3-2 to Sheffield with a one-timer, assisted by Connolly and Brocklehurst; the only black mark being an off-the-puck injury to Vallerand, who later returned to the ice.
Three unanswered goals in seven minutes had tipped the balance in coach Aaron Fox's favour.
But the third period brought the visitors down to earth with a bump, Riley levelling at 3-3 with Tanner Eberle in the penalty box. Fifty seconds later, the rattled Steelers conceded a fourth from Joey Haddad. The goal was Devils at their best...but the best from Steelers was yet to come.
Armstrong had a chance to get his second before Sheffield finally equalised with Lucas Sandström tipping in Michael Davies' shot at 54:03.
It was all Steelers - and they took the lead again through the dogged, predatory instincts of Vallerand at 56:01.
A tremendous result for Sheffield - but Fox knows there will be plenty of twists and turns in the coming weeks.