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People: What kind of gas mileage do you get in that thing?

Me: … it’s complicated

Them: why?

Me: attempting to explain 4Xe Wrangler in simplistic terms and failing

Them: oh… ok…

Me: … it’s complicated


This common convo is best part about owning a 4Xe haha

I just tell them I'm currently getting about 24, 35, and 85 mpg on mine.
 

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I just tell them I'm currently getting about 24, 35, and 85 mpg on mine.
I like that. Probably would get about the same response as I get haha
Agreed, it’s difficult to explain. I found it’s just easier to say how much I drive, how often I charge, and how often I get gas.

”I drive around 1100 miles/month, charge it at least once everyday, and fill up the tank from half every 4-5 weeks.”

That usually gets people to understand when they respond. “Wow, I have to get gas every 5 or 6 days!”
 

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2022 Granite 4xe Rubicon
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So as I understand, the 4xe is different than most other PHEV's whereas the 4xe's main electric motor is inline with the ICE powertrain and engaged through clutches. In contrast on other PHEV's, somewhat independent electric motor/generators, not inline with the ICE drivetrain, are used to provide power to the wheels.

In other PHEV's, the faster you drive, the more electric energy is used. This is almost directly proportional. This is because there is limited or no gear reduction/transmission. The 4xe uses the primary electric motor in direct conjunction with an 8 speed transmission, using varying amounts of electric energy at speeds/gears, similar to the way it would vary in efficiency with gas. Does that make sense? So at the end of the day, with considerations to terrain, wind speeds, etc....whatever speed/gear you would find the best fuel economy, should be where you'll find the best electric economy.

Does anyone know where the sweet spot is for max fuel/electric economy in the 4xe?
 

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I'm just trying to figure out what the hybrid system does other than burn no gas for 20 miles and add dead weight the rest of the time. No other PHEV works this way. A non-hybrid 2.0 turbo gets combined mpg of 20. It seems illogical that the 4xe would also get just 20 mpg once the vehicle can no longer run entirely on battery since we know it reserves 15% of the battery. Even the behemoth new Toyota Sequoia gets a mild bump with it's puny 1.8 kwhr battery. Why wouldn't the Wrangler? In any event, it does sound like many are getting a 20-30% improvement in fuel economy when running in hybrid mode. That's all I'm asking.
So as I understand, the 4xe is different than most other PHEV's whereas the 4xe's main electric motor is inline with the ICE powertrain and engaged through clutches. In contrast on other PHEV's, somewhat independent electric motor/generators, not inline with the ICE drivetrain, are used to provide power to the wheels.

In other PHEV's, the faster you drive, the more electric energy is used. This is almost directly proportional. This is because there is limited or no gear reduction/transmission. The 4xe uses the primary electric motor in direct conjunction with an 8 speed transmission, using varying amounts of electric energy at speeds/gears, similar to the way it would vary in efficiency with gas. Does that make sense? So at the end of the day, with considerations to terrain, wind speeds, etc....whatever speed/gear you would find the best fuel economy, should be where you'll find the best electric economy.

Does anyone know where the sweet spot is for max fuel/electric economy in the 4xe?
In regards to maximum range at a constant speed, electric mode, guessing 25mph, gas, guessing 45-50. Depends on what accessories you have on. (Backround energy waste, alters ideal speed because you’ll waste less of if you’re on the road for less time)

Peak EV efficiency I believe generally like 15-25 mph. I don’t see that changing much because ours has a transmission.

ICE is I believe is usually around 50mph depending on drag coefficient amongst other things. Guessing our metal boxes are more like 40mph.
 

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While you're correct, i think you oversimplified a little bit. The Wrangler looses tremendous efficiency because of aerodynamics and it effects electric more than ice operation. 55 - 60 is likely the most efficient constant speed for the ice whereas it's like closer to 30 for the electric (assuming constant speed and no regen benefit).

So as I understand, the 4xe is different than most other PHEV's whereas the 4xe's main electric motor is inline with the ICE powertrain and engaged through clutches. In contrast on other PHEV's, somewhat independent electric motor/generators, not inline with the ICE drivetrain, are used to provide power to the wheels.

In other PHEV's, the faster you drive, the more electric energy is used. This is almost directly proportional. This is because there is limited or no gear reduction/transmission. The 4xe uses the primary electric motor in direct conjunction with an 8 speed transmission, using varying amounts of electric energy at speeds/gears, similar to the way it would vary in efficiency with gas. Does that make sense? So at the end of the day, with considerations to terrain, wind speeds, etc....whatever speed/gear you would find the best fuel economy, should be where you'll find the best electric economy.

Does anyone know where the sweet spot is for max fuel/electric economy in the 4xe?
 

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Yeah, I suppose we are also talking about significantly less torque produced by the electric half of the whole setup compared to the 2.0t
 

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This article really puts EV efficiency into perspective. A couple guys went 606 miles on a single charge in a tesla model 3. I think they have an EPA range of like 320 miles. They went 20-30mph for 32 hours.

It only took 32 hours of continuous driving in sweltering temperatures, but two Colorado residents have set a new “hypermiling” record by driving their Tesla Model 3 606.2 miles (975 km) on a single charge. It beat a previous record of 560 miles from a Tesla Model S P100D, but it fell slightly short of a 670-mile run in a Model S by an Italian team last August.

Hypermiling is a technique used to conserve gas (or in this case, electricity) that involves driving at a low, consistent speed with minimal use of the vehicle’s brakes. Colorado residents Sean Mitchell and Erik Strait set out to achieve a record in their Model 3 last week, aiming to hit 675 miles on a single charge. They fell short of that goal, but they still achieved a record for the Model 3.

Their journey into the record books started out at a Supercharger near Denver International Airport. From there, the pair drove in a 1-mile closed loop at speed of 20 to 30 mph, stopping occasionally to use the bathroom and acquire food from friends using a net they held out the window.
 

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A Tesla model 3 has a single gear reduction ratio of 8.2752:1. I've wondered what kind of range could be achieved if a Tesla had even one additional gear, with an even higher ratio for highway driving.
 

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A Tesla model 3 has a single gear reduction ratio of 8.2752:1. I've wondered what kind of range could be achieved if a Tesla had even one additional gear, with an even higher ratio for highway driving.
Probably less. Would just add more drivetrain loss.
You’re thinking like a gas motor.

An electric motor doesn’t use more energy when it’s at higher rpm. I mean there are minor differences based on rpm, but nothing like a gas motor.

Imagine car A has an electric motor spinning at 8k rpm going 50mph at a 10:1 gear ratio. Car B has a 5:1 gear and now it’s spinning at 4k rpm going 50mph.

To oversimplify it:
RPM is dictated by volts, torque is dictated by amps, hp = watts.

So the motor spinning at 8k rpm would have approx double the voltage and half the amperage as the other one because the 10:1 ratio would require half the torque of the 5:1 ratio. In the end they are consuming about the same wattage. Well in reality they would wind the motor differently to perform under the desired rpm range, but you get the picture.

In a gas motor it’s kinda similar in that going 50mph in 3rd gear requires more rpm but less torque than going 50mph in 4th gear. Unfortunately for gas powered motors they are fickle bitches and can’t just inject exactly 20% less fuel at 20% higher rpm just because you’re at 20% less load.
 

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Electric motors do tend to use more electricity at higher rpms... Whether you're facing wind resistance, or just friction, going faster takes more energy. Most electric motors are doing some kind of work; i.e. propelling our car, turning a fan blade, reciprocating a piston on an A/C compressor (it was hot today!) and as resistance goes up with speed so does consumption.

Probably less. Would just add more drivetrain loss.
You’re thinking like a gas motor.

An electric motor doesn’t use more energy when it’s at higher rpm. I mean there are minor differences based on rpm, but nothing like a gas motor.

Imagine car A has an electric motor spinning at 8k rpm going 50mph at a 10:1 gear ratio. Car B has a 5:1 gear and now it’s spinning at 4k rpm going 50mph.

To oversimplify it:
RPM is dictated by volts, torque is dictated by amps, hp = watts.

So the motor spinning at 8k rpm would have approx double the voltage and half the amperage as the other one because the 10:1 ratio would require half the torque of the 5:1 ratio. In the end they are consuming about the same wattage. Well in reality they would wind the motor differently to perform under the desired rpm range, but you get the picture.

In a gas motor it’s kinda similar in that going 50mph in 3rd gear requires more rpm but less torque than going 50mph in 4th gear. Unfortunately for gas powered motors they are fickle bitches and can’t just inject exactly 20% less fuel at 20% higher rpm just because you’re at 20% less load.
 

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Electric motors do tend to use more electricity at higher rpms... Whether you're facing wind resistance, or just friction, going faster takes more energy. Most electric motors are doing some kind of work; i.e. propelling our car, turning a fan blade, reciprocating a piston on an A/C compressor (it was hot today!) and as resistance goes up with speed so does consumption.
Yeah but an electric motor spinning twice the speed with twice the mechanical advantage is not doing more work.

The guy I was responding to was asking what efficiency could be gained by adding another gear ratio to a tesla. The answer is none, because the work for a tesla to travel 50mph isn’t changing even though the rpm of the motor is changing. It doesn’t matter if that motor is spinning at 10,000rpm @ 50mph or 15,000 rpm 50mph, the work doesn’t change.
 

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I'm not sure that's entirely true either because of the losses of what ever the mechanical advantage is; i.e. the transmission. But, yeah, it's better than an ICE, unfortunately.

Yeah but an electric motor spinning twice the speed with twice the mechanical advantage is not doing more work, which was the premise of my post.
 

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I'm not sure that's entirely true either because of the losses of what ever the mechanical advantage is; i.e. the transmission. But, yeah, it's better than an ICE, unfortunately.
Yeah there are more friction losses with greater mechanical advantage. I’m using extreme figures to answer the guys question so he understands.

In the real world, if tesla use an 8.2:1 ratio now, and they incorporated a 2 speed trans for highway driving, with the highway gear being say, 5:1, any slight gains with the taller gears would be offset my the mechanic losses with the more complex 2 speed trans.

EV’s gain an acceleration advantage using transmissions, not an efficiency advantage
 

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I read somewhere that the Jeep Wrangler has the aerodynamics of a cow... What I have noticed is driving the same distance on the highway at high speeds vs. city streets it is much more efficient at slower speeds.

Wracked my brain for a while and then realized the issue is wind resistance. I'm sure there's lots I don't understand about how engines work but this seems pretty straight forward.
 

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The Wrangler wishes it was as aerodynamic as a cow... Cows are really smooth and rounded. It's more of a flying brick, i think.

I read somewhere that the Jeep Wrangler has the aerodynamics of a cow... What I have noticed is driving the same distance on the highway at high speeds vs. city streets it is much more efficient at slower speeds.

Wracked my brain for a while and then realized the issue is wind resistance. I'm sure there's lots I don't understand about how engines work but this seems pretty straight forward.
 
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