Maurizio Sarri finally fielded Ronaldo, Paulo Dybala and Gonzalo Higuain together from the start – and the trio were influential in helping the reigning champion record a first victory in three league outings.
The result was a formality by half-time at Allianz Stadium, Ronaldo getting a brace as Udinese struggled to cope with a pumped-up home team eager to bounce back from a 3-1 loss away to Lazio the previous weekend.
The Portugal international opened the scoring in the ninth minute, firing home a loose ball with an instinctive first-time effort, while it was Higuain's well-weighted throughball that set up for a second, finished with his left foot.
Leonardo Bonucci added a third before the interval, flicking in a header at a corner from centre-back partner Merih Demiral via a deflection off the underside of the crossbar, allowing Juve to ease up in the second half.
As the tempo dropped, the hosts relied on the evergreen Gianluigi Buffon - making his 478th Serie A appearance in place of the injured Wojciech Szczesny, drawing him level with Alessandro Del Piero's club record in the competition – to keep Udinese at bay.
The veteran goalkeeper - guilty of a costly error in the 2-2 draw against Sassuolo earlier in December - twice denied the lively Kevin Lasagna, while he also turned away a fierce drive from Seko Fofana.
However, there was little Buffon could do to stop Ignacio Pussetto getting a consolation goal in stoppage time, preventing the former Italy international recording a clean sheet.
Ronaldo had been denied a hat-trick by the post in the closing minutes but Juve coasted to a result that sends them above Inter, although the Nerazzurri can reclaim top spot when they travel to Fiorentina in Sunday's late kick-off.