Is using 5th gear at 40mph messes up my engine?

[Syroyizhka]

I was driving with my friend the other day, and he yelled at me for using the fifth gear when i was going like 44 mph, I usually use it after 40 mph if driving on an even payment, however if its slightly up the hill I use 4th or even 3rd. He claims that he only uses the 5th on his Scion after 60 mph. Should i listen to him? cuz i think the manual said after 45 mph it was alright to use 5th. what are the most fuel efficcient speeds to change the gears, considering you're driving on a even payment?

[at3GG]

hmmm i use it sometimes at 30-35 when im not paying attention....no problems yet lol

[supmet]

I've heard 45 in 5th gear is the most fuel efficient the yaris can be. I've never heard it being bad for the car...

[Syroyizhka]

would it take more gas if I was going 40mph in 5th gear, even though i felt no stress on the engine, judging by the way it sounds and feels? (its pretty easy to tell when the engine is struggling in certain gear)

[at3GG]

me either....dont know why it would be?

[SailDesign]

I'll cruise at 45 in 5th on flat pavement. No problems. At that speed the engine is doing 1950 rpm, so as long as you down-shift for a hill ,you're not straining the engine. That rpm in 3rd gear is 28mph, and no-one will accuse you of straining the engine there.

[ChinoCharles]

We have a modded black hatch in Cleveland?! COME OUT OF THE WOODWORK FINE SIR!

[roxy1]

40 mph in 5th gear no problem and excellent mileage.

[Loren]

You'll hear this sort of thing from old school guys... or guys who have learned things from old school guys. The thing is, they're trying to compare the sophisticated 1.5 liter twin-cam, 16-valve, fuel-injected, variable valve timed Yaris engine to... some similar displacement 8-valve, carburetted, 70's era emissions choked engine. The Yaris engine makes at least 75% more power and torque than the low-tech equivalent, and it can handle running at low RPM just fine.

If you're NOT climbing a hill or carrying a lot of weight, and you don't mind accelerating slowly (or you're cruising), you're not going hurt the Yaris engine going even as low as 35 mph in 5th gear. Of course, if you're carrying a load or going uphill, use a lower gear.

[Syroyizhka]

Originally Posted by Loren

You'll hear this sort of thing from old school guys... or guys who have learned things from old school guys. The thing is, they're trying to compare the sophisticated 1.5 liter twin-cam, 16-valve, fuel-injected, variable valve timed Yaris engine to... some similar displacement 8-valve, carburetted, 70's era emissions choked engine. The Yaris engine makes at least 75% more power and torque than the low-tech equivalent, and it can handle running at low RPM just fine.

If you're NOT climbing a hill or carrying a lot of weight, and you don't mind accelerating slowly (or you're cruising), you're not going hurt the Yaris engine going even as low as 35 mph in 5th gear. Of course, if you're carrying a load or going uphill, use a lower gear.

thanx, rather know these things now rather than later...

[AlexNet0]

absolutely, I spend most of my time, now 60k miles on back road rural areas mostly around 40-45-50mph almost all of it is in 5th gear, no engine or tranny problems at all

[Syroyizhka]

Originally Posted by ChinoCharles

We have a modded black hatch in Cleveland?! COME OUT OF THE WOODWORK FINE SIR!

yes i had it for 6 months not many yaris hatchbacks here in cleveland, and with the rear yaris sign taken off, people call it a mystery car

[Kal-El]

Originally Posted by Syroyizhka

I was driving with my friend the other day, and he yelled at me for using the fifth gear when i was going like 44 mph, I usually use it after 40 mph if driving on an even payment, however if its slightly up the hill I use 4th or even 3rd. He claims that he only uses the 5th on his Scion after 60 mph. Should i listen to him? cuz i think the manual said after 45 mph it was alright to use 5th. what are the most fuel efficcient speeds to change the gears, considering you're driving on a even payment?

Sorry, but your friend knows nothing about cars. Being in 4th at 44 mph is actually starting to rev your engine higher than it should while cruising on flat ground. Keeping it in 4th until 60 (in a 4 cylinder car) is now racing your engine and should only be done if you need hard acceleration or actually going almost 60 uphill. So, if your just cruising on flat ground, you should shift into 5th after 40 mph for optimal mileage and the least amount of engine wear.

[IllusionX]

1500rpm on a flat surface is the bare minimum.

37mph would be the bare minimum in 5th@1500rpm. Actually it's more like 35-36mph, or a tad under 60kmh...

[Lafiro]

And what kind of milage are you all getting by doing this?

Wish I could, I mean at night the main highway is doing 65mph.... and the two lane state highway is at 75mph.....

Can't really be driving slow and causing trafic you know..

[nerp]

I drive 40-45 in fifth all the time. I average 40-42mpg this way.

[DerFlosser]

The threat is if you lug the engine. 40 in fifth on flat pavement is fine.

[Yaris Hilton]

There's no "threat" to "lugging the engine." Won't harm it, as long as you're not causing heavy detonation. Accelerating at ~70-80% load at RPMs peaking in the 1500-2000 RPM range before upshifting is a popular approach to improving fuel economy with a manual transmission in Yaris-class cars.