Prius on Motorways

[Berengaria]

Considering realising some capital by selling my low mileage petrol Avensis and buying an older Prius with higher mileage for less money.

I don't lot of motorway driving, so need something that isn't revving tiresomelywhen cruising at 70mph. I know the Prius is a CVT, but on a flat road with gentle throttle to maintain speed at 70mph what revs would a Prius Gen2 or Gen3 be doing at that speed?

[ian rooke]

The prius has not got a rev counter

[kithmo]

The Gen 2 would be revving more than the Gen 3, but I wouldn't say either was tiresome at 70 mph.

[Anthony Poli]

From my own experiences, I would say the road noise is more noticeable than engine revs at 70 with the cruise control. Maybe going up quite a steep hill on the motorway its a different story. My previous car was a 2004 corolla verso and to be fair I didn't consider that loud, but in a hybrid there will be moments when you are  guessing is the engine actually running. 

[PeteB]

10 years ago I took an original Gen 1 1.5 Litre Prius on a tour of Scotland, where we encountered some very serious hills.

A few were 1 in 5 (20%) inclines that lasted 5-6 miles.  With the cruise control set to 60 mph, the car was very relaxed and the engine did not feel or sound as though it was revving that hard.  It was not drawing on the Hybrid Battery either.  (Going down the other side was interesting, when the Battery maxed out half way down!).

As has been said, each later version of the Prius used lower revs in a given situation that the one before, so I wouldn't find it a problem.

My previous Gen 3 was very effortless on the steep hills on a trip in Devon last year too.

[danowat]

Technically it's not a CVT, it's an eCVT, they are quite different.

As for revs, you can use this simulation of the eCVT to give you an idea of the revs at any speed.

http://eahart.com/prius/psd/

FWIW, I can't hear the engine at a steady 70mph.

[Anthony Poli]

Probably the only time I hear the engine, is usually  on those hills where there is no opportunity to build up enough speed or momentum and you are forced to push harder on the accelerator. 

 

[johalareewi]

20 hours ago, Berengaria said:

on a flat road with gentle throttle to maintain speed at 70mph what revs would a Prius Gen2 or Gen3 be doing at that speed?

There isn't a simple answer because there are 2 engines. A petrol one (ICE) and an electric one.  Toyota hybrids use both at the same time and blend the power from each.

So you could be using the electric engine to overcome any friction and air resistance, or a little bit of ICE (say around 1500 rpm), or a mix.

Can you take one for a test drive on the M6?

[danowat]

According to the simulation I linked, the minimum amount of ICE rpm, at 70mph, is 1200rpm.

Incidentally, at this speed the MGU1 is doing -6500rpm and MGU2 +4200rpm

[QuantumFireball]

The simulation probably doesn't take into account external factors like rolling resistance, wind resistance, etc.

IIRC my 3rd gen Prius stays around 1800-2000 RPM on a flat road at 120 km/h (75 MPH). I can barely hear the engine at all. As others have said, road noise is the bigger issue at these speeds.

I believe the previous generation would be running at higher revs for similar speeds, but I have no personal experience.

[Cyker]

Yikes... I can't imagine the car would let the MG1 be run at -6000rpm for long periods of time!

Also, the ICE maxes out at 4500rpm in that thingy... I'm sure it revs higher than that??

[Berengaria]

Thanks everyone for your contributions - very informative.

 

The last few posts kind of touch upon the nub of things for me - the thought of either the engine or motor spinning at very high revs (3k+) for two hours solid doesn't seem very good for the mechanicals to me, particularly the Gen2 with a relatively small 1.5cc engine (small engine = smaller picces inside whirring around).

 

I was a passenger in a Gen2 a few years ago now, and from what I can remember, the journey on motorways and fast roads tended to be a mixture of the engine kicking in with very high revs (especially on acceleration; a bit like doing a kick-down on a traditional auto) and quieter periods.

 

I would be using it for regular motorway journeys lasting 2 hours, so especially with an older one (with what I'd be looking to spend, it would probably be 10 years old with upwards of 50k miles on the clock)  my concern is that a long journey at high revs would strain the mechanicals and lead to a breakdown with an expensive repair on what seems like a more complicated car. That said, from what I read about the Prius, it seems like despite being high-tech the drivetrain is very reliable; even in higher mileages - is that view correct?

[Anthony Poli]

Some owners have clocked up 300,000 or more and without any major issues. Maybe the 0w20 oil might explain it.

As for revs, it depends on what speed you would be driving, when I first had mine, I did worry that I would break it. Over time I have gained confidence in the hybrid system and have adjusted to getting the best out of the car. 

 

[danowat]

11 hours ago, Berengaria said:

my concern is that a long journey at high revs would strain the mechanicals and lead to a breakdown with an expensive repair on what seems like a more complicated car. That said, from what I read about the Prius, it seems like despite being high-tech the drivetrain is very reliable; even in higher mileages - is that view correct

You could argue that the components of a hybrid are under much less stress than those of an ICE only car, as the load is shared across the MGU's and the ICE, and the way the transmission works, it means the ICE has to work much less harder, 70mph wouldn't be "high revs", the ICE is barely working above tick over on a flat road at 70mph.

I wouldn't worry about the MGU's spinning at high(er) revs, DC motors are quite reliable, and have little axial stress to deal with, as for it being a complicated car, hell yeah it is, but that complication also has benefits, for example the transmission only has 20 moving parts, as opposed to a mechanical gearbox that has 100+.

There is also the fact that the engine isn't an Otto cycle, it's an Atkinson, which means the engine is more efficient and runs cooler, plus there are no ancillary belts, all the pumps are electric.

Quote

I was a passenger in a Gen2 a few years ago now, and from what I can remember, the journey on motorways and fast roads tended to be a mixture of the engine kicking in with very high revs (especially on acceleration; a bit like doing a kick-down on a traditional auto) and quieter periods.

This will depend on how you drive, if you plant the throttle, the ICE will push to the limit and stay there (there is no 'kick down'), which for someone used to a car with just an ICE feels odd and strained, the car requires a certain driving style to get the best out of it.

Is a Prius for you?, TBH, I'd say no, it sounds like you are trying to find reasons not too, and in terms of economy and servicing costs, you'd probably be better off with a diesel, however, the next few years are going to be quite telling for diesels, I expect that there will be increases in tax in the near future.

I should probably add that I have only owned a Prius for a little over 2 weeks!, but in those two weeks I have found the car to be very unstressed, and it regularly returns 70+ mpg on my 20 mile mixed dual carriageway / A road / B road / city commute.

[QuantumFireball]

14 hours ago, Cyker said:

Yikes... I can't imagine the car would let the MG1 be run at -6000rpm for long periods of time!

MG1 is designed to run between +/-10k RPM, so it's well within normal operating specs. It's not an ICE, so motor speeds are not really comparable. Motors in Dyson vacuum cleaners run at over 100k RPM, for example.

Essentially you don't need to worry about it. The ICE is much more likely to fail than the MGs/transmission, e.g. head gasket failures, which are not unheard of with the Prius - but still very rare.

It's as capable as any other ICE car for long journeys, maybe even more so - I've done trips of over 250 miles, and would have no concerns driving the thing across Europe. They are extremely popular in Mongolia, a country with much more arduous conditions than ours (only about 10% paved roads?), and have proven to be very reliable. The 3rd gen is a marked improvement regarding performance and refinement for motorway driving though, so if that is the majority of your driving I would recommend that.

[johalareewi]

14 hours ago, Berengaria said:

from what I read about the Prius, it seems like despite being high-tech the drivetrain is very reliable; even in higher mileages - is that view correct?

In a word, yes.

[Mkuk0]

Keeping it simple, I had a Gen 2 (2009 model) for 4 years as a company car, during which I put 80k+ miles on the clock, the majority of which were motorway miles.  The car never missed a beat, at motorway speeds tyre noise was more intrusive than engine noise, the only time you became aware of the engine was if you pushed the throttle hard, ie to overtake. My daughter now has that car, and has put a further 30k miles on it and its still as solid as a rock.

 

You want one, go for it, you won't regret it.

[Sooty]

1 hour ago, Mkuk0 said:

Keeping it simple, I had a Gen 2 (2009 model) for 4 years as a company car, during which I put 80k+ miles on the clock, the majority of which were motorway miles.  The car never missed a beat, at motorway speeds tyre noise was more intrusive than engine noise, the only time you became aware of the engine was if you pushed the throttle hard, ie to overtake. My daughter now has that car, and has put a further 30k miles on it and its still as solid as a rock.

 

You want one, go for it, you won't regret it.

I fully agree with this.

My Gen 2 has 90K on the clock, I have done 58K of those. A lot has been motorway driving and I don't hang about.

At 75 - 80 MPH I only hear the ICE if I boot it to pass another vehicle or if going up steep hills with my right foot down near the floor.

Generally a very quiet car.

[PeteB]

Same here.  My 2nd Gen 1 Prius has 8k on it when I got it and 163k 9 years later when I sold it.  No problems at all on motorways, and each later version just got better.

Engine was still fine, but started to use a little oil between services (just added  litre after 6-7,000 miles).

Some time ago I heard it has passed 180k with its current owner.

[danowat]

I know it's off topic, but what is the highest mileage Prius around?, I heard of one with 600'000 on the original batteries, and I've seen a smattering of 300 - 400'000 mile ones.

[MEP's Yaris GS]

7 hours ago, danowat said:

I know it's off topic, but what is the highest mileage Prius around?, I heard of one with 600'000 on the original batteries, and I've seen a smattering of 300 - 400'000 mile ones.

http://blog.toyota.co.uk/bob-old-and-his-435000-mile-hybrid

[Anthony Poli]

21 minutes ago, MEP's Yaris GS said:

http://blog.toyota.co.uk/bob-old-and-his-435000-mile-hybrid

He had racked that up in the 9 years of owning the car, just wondering if he still has the same car .

[Berengaria]

13 hours ago, danowat said:

Is a Prius for you?, TBH, I'd say no, it sounds like you are trying to find reasons not too, and in terms of economy and servicing costs, you'd probably be better off with a diesel, however, the next few years are going to be quite telling for diesels, I expect that there will be increases in tax in the near future.

From what I'm hearing from people, a Prius could well be for me - reliable, an engine that isn't stressed, and simple yet robust mechanicals. Coupled with the economy and low VED, it seems like a justifiable choice. Only real real consideration is that at any age a Prius is expensive compared to the same age conventional car. £3-4k for a 12 year old car is quite expensive. The worth of my 12 plate Avensis probably only gets me a 09/10 plate Prius.

Yes, diesel cars are good for long trips, but require more maintenance than petrol and have more to go wrong. I had already discounted them for that reason, plus I live in an area where those with derv cars are likely to be punished very soon. That's the good thing about my petrol Avensis - diesel like economy without the nonsense, so should become more virtuous as a secondhand buy very soon.

A bugbear with the Avensis electronic parking brake coupled with manual transmission. A final question therefore is whether the Prius parking brake is wholly electronic or manually/mechanically operated via the pushing of the foot brake pedal?

[Anthony Poli]

9 minutes ago, Berengaria said:

From what I'm hearing from people, a Prius could well be for me - reliable, an engine that isn't stressed, and simple yet robust mechanicals. Coupled with the economy and low VED, it seems like a justifiable choice. Only real real consideration is that at any age a Prius is expensive compared to the same age conventional car. £3-4k for a 12 year old car is quite expensive. The worth of my 12 plate Avensis probably only gets me a 09/10 plate Prius.

Yes, diesel cars are good for long trips, but require more maintenance than petrol and have more to go wrong. I had already discounted them for that reason, plus I live in an area where those with derv cars are likely to be punished very soon. That's the good thing about my petrol Avensis - diesel like economy without the nonsense, so should become more virtuous as a secondhand buy very soon.

A bugbear with the Avensis electronic parking brake coupled with manual transmission. A final question therefore is whether the Prius parking brake is wholly electronic or manually/mechanically operated via the pushing of the foot brake pedal?

Remember the Prius isn't the only hybrid 

[kithmo]

Mechanical parking brake via foot pedal and electronic transmission lock via "P" button which also automatically engages when you turn the car off.