2017 2.0 petrol vs. 2.5 Hybrid

[mm450exc]

Been looking at the RAV4. Hybrid vs. petrol.

Hybrid just has a bit more weight, bit lower ride height (?), different four wheel drive system (electric rear). What is the real mpg difference? Anybody had both. Which one did you like better and why?

[FROSTYBALLS]

Initially have a look at the Honest John Real mpg pages - https://www.honestjohn.co.uk/realmpg/toyota/rav4-2013

[IanML]

You would expect the hybrid advantage to predominate if you do a lot of stop/go town driving - the energy recovery from decelerating and operating the engine mainly as a generator at best rpm.  If you do mainly long motorway trips, do not expect much advantage.

[mm450exc]

Drove both and only a minor difference on a short test drive.

How about the CVT transmission? Nice and simple. Does it work well and reliable?

[Mike169]

Hi.

I suggest you find out the exact name of the gearbox as there is one system that is troublesome and costs fortunes to repair.

Regards, Mike.

[PeteB]

The so-called eCVT transmission in Toyota Hybrids is generally regarded as bullet proof and nothing like the CVT system in most other cars (including most Honda Hybrids) that have it.

The Toyota system (sometimes called a planetary transmission) is fairly uncomplicated with a single central cog (Sun Gear), 3-5 (Planet) cogs around it in a carrier with a ring on the outside with its teeth innermost and meshing to the planet cogs.  One is connected to the main electric motor, one to the petrol engine, the other to the wheels.  Nothing slips, engages or disengages, swaps cogs etc.  There's no clutch or torque converter, it's so simple it's beautiful.  If one of the three pieces changes speed, one or both the others must change to compensate - for example:

• car is stationary, engine starts to charge the Battery, the main Motor/Generator (MG) must spin the other way.
• car starts to reverse (engine not running), MG turns the other way.
• using cruise control at 60 mph, come to a steep upwards hill: engine revs increase (car stays at 60), MG must reduce rpm proportionally (or even spin the other way).
• hard acceleration, car speed increases, engine revs stay constant - MG slows (possibly reverses direction) proportionately to car's speed increase.

Some nifty graphics are in this page: http://prius.ecrostech.com/original/PriusFrames.htm

Conventional CVT gearboxes contain a system of cones with a flexible steel belt and as the cones move closer and further apart the band is squeezed and changes ratio continuously, but this systems needs a clutch or torque converter to handle being stationary with the engine running while in gear.

There is a simple diagram in this explanation: https://en.wikipedia.org/wiki/Continuously_variable_transmission

I've driven a number of cars with 'conventional' CVTs, including Mk2 Nissan Micra auto, Honda Jazz CVT, Honda Civic Hybrid and Honda Insight Hybrid and they behave uncannily like each other and the technically different Toyota eCVT in response to accelerator operation.