2025 model year: CVT, transmission, or one gear direct drive?

[twiggy144]

I am confused about how the front wheels are driven by the ICE. First I tought there was a CVT, but I am getting information it is a direct drive, using one reduction gear only.

What would be the reduction ratio of this single gear ? Also, if there some kind of a clutch to disengage the ICE from the front wheels?

Thanks for your input! Love this forum!

 

[AndyInOz]

I like to post this explanation of the GKN e-Drive when people ask questions like this:


https://www.gknautomotive.com/en/sy...ic/multi-mode-dedicated-hybrid-transmission2/

There is a hydraulic clutch inside the e-Drive, which operates only when the engine is driving the front wheels.

Unfortunately, I don't have any info on the gear ratio.

The car also has two 'transfer cases' which split the power from the motors between the wheels as required. (i.e. front motor left/right, rear motor left/right).

I suspect that transfer cases were used because it suited the East/West alignment of the electric motors, and also because they take up less space than a differential, but that's beyond my skill set...

 

[twiggy144]

A picture is worth a thousand words. An animated picture is worth even much more. Thanks!

Looking at the animation, and guessing the respective different diameters of the gears, I am roughly guessing the gear reduction ratio is in the range of 4:1 to 2:1 ; in other words, a low gear. The gear reduction ratio is probably in the same range as the gear reduction ratio of the first or second gear of the 3 speed automatic transmission installed in cars from the 60's and 70's. For the record, my first car was a 1975 Ford Pinto with a 3-speed automatic transmission.

 

[AndyInOz]

I'm not so sure of the above.

The engine doesn't directly drive the front wheels at speeds below 80 kph (IIRC) so it is more likely to be a 'high gear' i.e. equivalent to forth or fifth.

I'm also pretty sure it's not an 'overdrive' because of the way the engine revs while at those speeds.

When I've driven cars with 'overdrive', the engine revs drop down to about 1500 rpm while maintaining speed on the flat, whereas the PHEV engine hovers around 3000 (according to my ear anyway).

Sorry I don't have more technical info for you, it must be documented somewhere, but I haven't been able to find it.

 

[PHEV07]

Read thru this plz.

https://saintleonardmitsubishi.com/en/mitsubishi-cvt-transmission

I will post more info when I get a chance.

 

[PHEV07]

Here is another video explaining the EV, Series and Parallel modes in 2018 model

 

[BobK]

Read thru this plz.

https://saintleonardmitsubishi.com/en/mitsubishi-cvt-transmission

I will post more info when I get a chance.

I think the first part is referring to the gas Outlander with CVT rather than the single gear GKN unit on the PHEV.

 

[DaveL59]

I guess the question tho is are the new platform models since the merger with Renault etc based on the same EV and drivetrain as the original Mitsu version?

I don't know and since the UK has no access to those I guess we've no easy way to verify.

 

[twiggy144]

Trying to determine the E-transmission gear reduction ratio. To calculate this, I need to know the engine RPM for a given speed, which I dont know yet. Until I know the engine RPM, I have assumed a RPM of 2000 at 100 km/h, and using this hypothesis, I can derive the E-transmission gear reduction ratio, as follows:

C = R / V * W x 60 minutes per hour x 1 kilometer / 1 000 000 millimeter

where:
R = engine RPM (revolutions per minute)
C = E-transmission reduction ratio
W = wheel circumference (millimeters)
V = vehicule speed ( km per hour)

and where:
W = wheel circumference = D x pi
D = wheel diameter = tire height x 2 + rim diameter


using a tire size of 235-60-18, we have :

tire width : 235 millimeters
tire height to width ratio : 60%
rim diameter : 18 inches

tire height = tire width x tire height to width ratio
tire height = 235 x 60% = 141 millimeters
rim diameter = 18 inches x 25,4 mm / inch = 457 millimeters
D = 141 x 2 + 457 = 739 millimeters
W = 739 x 3,1416 = 2322 millimeters

this means for each complete revolution of the wheel the vehicule moves by : 2322 millimeters


Going back to my first equation :
C = R / V * W x 60 minutes per hour x 1 kilometer / 1 000 000 millimeter
and assuming a RPM of 2000 RPM at 100 km / hour, we have:

C = 2000 / 100 km / hour x 2322 millimeter x 60 minutes per hour x 1 kilometer / 1 000 000 millimeter
C = 2.78

Conclusion: the E-transmission gear reduction ratio (ICE engine to wheel reduction ratio) is 2.78.

This number compares to a conventional transmission in "high gear" where the gear reduction ratio is close to 1.0 to 1, but also where the reduction ratio of the differential is close to 3.0 to 1, for a total net reduction ratio of 1.0 x 3.0 = 3.0.

Any comments ?

 

[AndyInOz]

Since your model depends on the RPM at 100 kph, it's a good idea to measure that value.

I would have guessed a higher value, say 3000 to 3500.

 

[twiggy144]

Since your model depends on the RPM at 100 kph, it's a good idea to measure that value.

I would have guessed a higher value, say 3000 to 3500.

I will measure true RPM as soon as I have the possibility, and report back here.

 

[littlescrote]

OBD scanner will tell you rpm.

But honestly, why bother?

 

[twiggy144]

OBD scanner will tell you rpm.

But honestly, why bother?

( I am a car mamiac. I am obsessed by mechanics. )

 

[michael8554]

Why not just measure the diameter of the wheel and tyre on the car ?
An average of the height up from the road contact point, and 90 degrees from that.

 

[twiggy144]

Good idea if you have a tire close by. I dont have my Outlander yet. Will be delivered next week. In the meantime, I used some calculations.

 

[twiggy144]

Also, I was curious how the single gear transmission was engineered.

Conventionnal transmissions have several gears with several reduction ratios to gradually and smoothly bring the car from stopped to full speed. CVT' s will do same but with infinite reduction ratios by design.

The single gear ratio of the Outlander's E-transmission is a "high gear" . Because of that, I suppose when starting the vehicule from stop, the electric motors are first used, and if required, the clutch that engages the ICE in parallel mode will do so when a minimum speed has been reached. It's difficult or impossible to start a conventionnal vehicule from stop with a high gear.

 

[AndyInOz]

Also, I was curious how the single gear transmission was engineered.

Conventionnal transmissions have several gears with several reduction ratios to gradually and smoothly bring the car from stopped to full speed. CVT' s will do same but with infinite reduction ratios by design.

The single gear ratio of the Outlander's E-transmission is a "high gear" . Because of that, I suppose when starting the vehicule from stop, the electric motors are first used, and if required, the clutch that engages the ICE in parallel mode will do so when a minimum speed has been reached. It's difficult or impossible to start a conventionnal vehicule from stop with a high gear.

I believe these things to be true.

With the Outlander PHEV, the electric motors are the primary drive, and always are 'running', providing the motive power to the wheels.

Once a speed is reached (I'm not certain, but I think it is 80 kph) the engine may also provide motive force to the front wheels via the e-Drive.

The car's driving modes are:

1. Electric - Power from the battery drives the electric motors.
2. Serial Hybrid - Power from the engine drives the generator which powers the electric motors (the battery is still in circuit, and will often be taking some charge in this mode).
3. Parallel Hybrid - Power from the engine drives the generator, and is provided to the front wheels.

There is also a 4WD mode, where the power to the electric motors is provided as a 50:50 split between the front and rear motors. That mode can be selected at any time.

At lower speeds, I believe that the car is usually only driving one motor (the front) and the rear motor only receives enough power to prevent it from acting like a brake.

Please note that this is all based on my model, which is ten years old now.

 

[littlescrote]

Also, I was curious how the single gear transmission was engineered.

Conventionnal transmissions have several gears with several reduction ratios to gradually and smoothly bring the car from stopped to full speed. CVT' s will do same but with infinite reduction ratios by design.

The single gear ratio of the Outlander's E-transmission is a "high gear" . Because of that, I suppose when starting the vehicule from stop, the electric motors are first used, and if required, the clutch that engages the ICE in parallel mode will do so when a minimum speed has been reached. It's difficult or impossible to start a conventionnal vehicule from stop with a high gear.

When you get one, you'll see. It will only engage the direct drive above 65kph and then because the engine speed is low and there is not much power available it often needs the assistance of the electric motor.

 

[evman77]

I think the first part is referring to the gas Outlander with CVT rather than the single gear GKN unit on the PHEV.

I have a 2019 and I'm pretty sure I have a direct drive for the ICE. If you use the power flow monitor on the screen you can see the change from direct drive back to EV drive when you slow down for the city. There is no downshifting needed.
On a trip back from the MITO service yesterday (110 KM) I was able to use EV drive with the ICM charging the battery even at 120KPH. It never switched to the ICM driving the wheels.

 

[twiggy144]

PArdon my ignorance. What are MITO and ICM?