It looks like ODOT is planning a grade separation for SH-4 at Fox Lane:
https://sh4atfoxlane.publicmeetinghub.com/alternatives-considered
The preferred alternative (3A2) is a diamond exit,
which is what they need to build, even if they end up having to build it in phases with first a Super 2 arrangement and then Interstate quality dual roadways.
All the at-grade alternatives on that page
suck. I can't even believe they have roundabouts as possible "solutions." Ugh. I pray the 3A2 alternative wins out. That would at least extend a 4-lane freeway from the OK-4/I-44 interchange a little farther. It's also important to note the ROW needed for the diamond exit at Fox Lane is already secure. In Google Earth you can see the easement barriers for the roadway based on how the terrain looks. ODOT or OTA could get a 4-lane freeway extended as far North as Rock Creek Road without having to buy any extra ROW.
ODOT would be wise to buy ROW at SH-37 for a grade separation.
They'll have to buy and clear several properties along OK-4 leading up to the OK-4/OK-37 intersection. Three of the four corners at that intersection are occupied by properties. ODOT/OTA would have to buy and clear the properties on at least one side of the road to make room for the freeway and exit. The Western side of the road has fewer properties, but some are going to be pissed about a church getting bulldozed to make way for a super highway. But it's something ODOT/OTA need to do to be honest. That H.E. Bailey turnpike extension needs to at least make it over the Canadian River (and those twin bridges they built in the 1990's). If a OK-4 freeway/turnpike could at least make it into the South edge of Mustang it would leave a fairly short
Breezewood along S Sara Road and OK-152. Over time ODOT/OTA could come up with some creative way to bridge that gap.
Is there still a 4 way stop at OK 3/OK 4? There was in 2007.
Do you mean the OK-3/OK-4 intersection on the Northwest outskirts of OKC? Or do you mean the
OK37/OK-4 intersection in Bridge Creek? In either case, the answer is yes.
Both intersections have traffic signals.