Thanks to new fuel-economy rules and an influx of excellent 4-cyl. engines, the V-6 is under pressure. Once an industry mainstay, auto makers are dropping the venerable powerplant at an alarming rate, most notably in the growing cross/utility segment.

Hyundai, Toyota and Ford no longer offer V-6s in their midsize CUVs for the ’13 model year. A surprising number of midsize sedans are going without as well, including the Ford Fusion, Kia Optima and Chevy Malibu.

Audi started offering only 4-cyl. engines in its entry level A4 several years ago in the U.S. Mercedes-Benz and BMW now offer I-4s in a growing number of their U.S. vehicles, although they still offer 6-cyl. engines.

Even the hefty Ford Taurus can be powered with an inline turbocharged 4-cyl. The 2.0L EcoBoost, a winner this year, landed in the fullsize sedan and the smaller Focus ST, and both produced excellent results.

In defense of the V-6, there are some excellent competitors – and winners – this year. Audi’s 3.0L TFSI, Chrysler’s 3.6L Pentastar, and Honda’s 3.5L all placed in this year’s competition, as well as BMW’s iconic 3.0L I-6.

But the competition among engine types is fierce. The industry seems to agree there always will be a market for 8-cyl. engines in muscle cars, fullsize pickups and big SUVs.

And then there are electric powertrains, which didn’t make the cut this year but still are ones to watch in the coming years as engineers continue to fine-tune their development.

So where does that leave the classic 6-cyl. engine? In many cases they are replacing V-8s, but that seems a bit too limited of a role.  

Historically, V-6s have dominated the 10 Best Engines list. Nissan’s superb VQ engine earned a spot for a record 14 years in a row.

Chrysler’s Pentastar V-6 is on a streak right now with three consecutive wins since its introduction, and it just proved it has no problem filling in for a smaller V-8 in a pickup. Audi’s 3.0L now has made it on the list four years in a row and left us feeling like we never need to see a V-8 again.

Increasingly the challenge auto makers face is finding the ideal use for the V-6. As this competition has shown, there still is a place for the V-6 when all the pieces come together.