Low RPM driving


#1

I drive a 1997 camry V6 with a 5 speed manual transmission. my daily trip to and from my job is 7 miles. To save on gas, I have begun driving my car by shifting up to 5th gear as quickly as possible, never going over 1400 RPM. When I get to 5th, I cruise at 1400 in 5th, which for this car is around 40 mph. I also take it out of gear and coast down hills letting the engine idle which it does at around 800 or 900 rpm. I’m getting better gas mileage, but I wonder if this way of driving is doing a number on my engine? This car, (probably one of only ten V6 manual camrys in the U.S. and the last year Toyota made the V6 Camry with a 5 speed,) can really get up and go and is a lot of fun to drive but not at $3.75/gal for 87 octane gas. thanks.


#2

Unless you’re lugging the engine no harm is being done.


#3

I agree.


#4

I too agree. No harm to machinery.


#5

When I’m “moseying along” in my '88 Accord LXi 5-speed I shift at 2000 (same firing rate as 1333 on a V6), maybe 2500 up an incline. Also reaching 5th gear ~40MPH. I get 25-28 MPG in the city. The engine runs great at 217K miles.


#6

I’ve been doing that with my truck lately and it’s jumped my milage about 4 mpg. The 1 thing I have to be careful with is it loading up on carbon. Every once in a while, I’ll lay into it on an on ramp and let the black smoke roll out the back.

I believe every once in a while you need to blow things out a bit when you do that, other than that, I don’t see a problem.

Skipper


#7

okay this is great; thanks very much–I didn’t want to wreck the car 1. getting hard to find manual cars in u.s. and 2. I want to drive this one into the ground so my next car can be an all electric vehicle.


#8

All electric in Chicago will at the least require a propane heater…


#9

I also take it out of gear and coast down hills letting the engine idle

Not a good thing to do. You should always be in gear so that you can gun it to get away from trouble. You will burn very little gas coasting in gear (in some cars, actually less), and you won’t overheat your brakes by riding them.


#10

Coasting downhill in neutral is unsafe, but I don’t think you are doing any harm to your car. If you drive an automatic gently and pay close attention to how it shifts, you might find it in top gear somewhere around 40 or 45 miles per hour.


#11

"I believe every once in a while you need to blow things out a bit when you do that, other than that, I don’t see a problem. "

According to a mechanical engineer friend: Another good reason to rev it up now and then is to prevent a ridge forming at the top of the upper piston ring travel. At high RPM the connecting rods stretch a bit and the rings go a little higher. If you go to a consistent, low top speed for many, many times then go higher the ring could hit that ridge and break.


#12

we don’t really have steep hills here. It’s more like gently rolling terrain. I have found that I get places almost as fast at 40 mph as I did before at 60 because traffic signals do a bit of evening things out. I never take it out of gear and coast in neutral. It’s always in gear but not engaged when I’m coasting. I bought this car in 2005. It is in great shape. The previous owners had to special order it. I am keeping it only because I have to make all-day cross country trips on expressways. Otherwise, I’d get a Smart Car or plug-in hybrid.