Dear Car Talk:
I have a new 2017 Honda Ridgeline. The speedometer is digital; it shows numbers only. It has no dial. However, it still has an analog tachometer. The transmission is an automatic 6-speed. Why do you need a tachometer with an automatic transmission? In the old days, the tachometer was a necessity for manual transmissions; with today's automatic computerized transmissions, it seems to be of little value. I would much rather have a speedometer dial instead of a tachometer. What do you think? -- Bill
There's no real reason a car with an automatic transmission needs a tachometer. You can drive that car 200,000 miles and never need to know what the engine speed is. Even if you shift it manually, the computer will prevent you from doing anything stupid, like over-revving the engine: It'll just cut off the fuel supply or spark when you approach the red line.
So why does it have a tach? Well, without it, there'd be a big hole in your dashboard. That wouldn't look good. They could put a clock there, but there's probably already a clock on the video screen.
I tend to agree with you. I prefer a speedometer dial to the digital readout. But you got what you got, Bill. There's hope for the future, however: More and more new cars are starting to come with customizable video displays instead of instrument clusters. So, instead of an analog speedometer, there's a high-definition LCD screen, and the computer creates an image of a speedometer that looks and acts like an analog speedometer, with a moving dial.
And with these displays, you can customize what you see on the instrument panel in front of you: You can make the speedometer and tachometer smaller, and see a large navigation map in the middle; or you can see your entertainment system's choices. You cansee "Judge Judy" yet, but that's probably coming.
And there's nothing stopping the manufacturers from letting you choose which instruments you want to see -- so you could have a speedometer instead of a tachometer, and your neighbor, Fred, could monitor his oil temperature in 7-inch grandeur. You'll be able to get that on your 2022 Ridgeline.
Actually, I find that there is one unsung advantage of a tachometer these days. Some cars are so quiet now that it's actually hard to tell if they're running. And with push-button ignition, you no longer remove the key after shutting off the ignition. So I'll admit to glancing at the tachometer from time to time, to make sure I've turned off the engine before I get out.