Engine RPM at 70 mph for Hybrid

[FredsMaverick]

Does anyone know the difference in engine rpm at 70 mph between the 24 and 25 hybrids? I know the final drive ratio changed from a 2.91 to a 3.37. I have had the truck up to about 80 mph and it felt relaxed to me. Thanks

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[FredsMaverick]

I have the AWD version I forgot to mention. That rpm seems really high?

 

[FredsMaverick]

What I meant is that when going 70 ot 80 mph the truck seems relaxed like it is revving at low rpms. But what you are telling me is that the rpms are on the high end but it doesn’t feel or sound noisy. I prefer lower rpms.

 

[The Cyber Orange Guy.]

How can it feel "relaxed" and "high"?

80 mph through the CVT with stock 225-75-17 tires is 2744 rpm w/2.91 vs 3178 rpm w/ 3.37




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Sorry that I put my EB nose here, is not that high ? My 2022 EB fwd ride at 70 and may be 80mph at 1500-1800ish rpm, I was under the premise that the whole thing of the hybrid trans was keeping the engine in a optimal rpm range to same more fuel.

Then why is so high the rpms ?

Can someone please explain it in a simple way ?

 

[FredsMaverick]

I don’t believe the hybrid revs that high. Does anyone have any insight on this matter? Like hooking up a scan guage?

 

[Pointyears]

Does anyone know the difference in engine rpm at 70 mph between the 24 and 25 hybrids? I know the final drive ratio changed from a 2.91 to a 3.37. I have had the truck up to about 80 mph and it felt relaxed to me. Thanks

How can you tell the RPM on a hybrid, especially with two motors?

 

[FredsMaverick]

It still uses a ICE.

 

[El Kabong]

I am (easily) confused.

The hybrid eCVT does not directly connect the engine to the final drive like an automatic which has locked it's torque converter or a manual gearbox. It is instead connected through a planetary gearset and so does not have a fixed drive ratio (of course, with AWD the PTU and rear diff have fixed ratios).

So I would think that the engine RPM is not directly linked to the speed of the vehicle - if for example you are doing 65MPH on level ground and the vehicle is operating in hybrid mode, then transition to a downhill slope, the amount of power demand should decrease, allowing the engine to slow its RPMs or even to shut off as the system goes into regenerative mode. Likewise if you are doing 65MPH on level ground and the vehicle encounters strong headwinds, power demand should increase and the system would call for higher engine RPMs in hybrid mode.

So what I'm saying is that I think the relationship of engine RPM to final drive ratio in our eCVT hybrids cannot be thought of using the models we are accustomed to with automatic or manual gearboxes where each gear has a fixed ratio of engine RPM to vehicle speed, because the eCVT uses a planetary gearset which can widely vary it's input to output RPM ratios.

Are these correct assumptions on my part or am I off in the weeds with this line of thought?

 

[FredsMaverick]

The hybrid transmission has no gears. The hybrid does not come with a tachometer. I think you can still get the gas engine rpms somehow.

 

[MaverickDragon]

AFAIK the 25+ Hybrids (XL / XLT / Lariat) don't have a tach, so unless someone is using a gauge, all you can tell about engine rpms is the sound...

 

[MaverickDragon]

Are these correct assumptions on my part or am I off in the weeds with this line of thought?

Sounds right to me...

 

[FredsMaverick]

You would have to have a good ear to determine the engine rpm lol. It is very quiet at high speeds. Sounds like the engine is revving low like 2000 rpm

 

[Hot Runr Guy]

The hybrid transmission has no gears. The hybrid does not come with a tachometer. I think you can still get the gas engine rpms somehow.

Get a ScanGauge3,,,,,,

HRG

 

[FredsMaverick]

I might have to but I thought someone on here would know the answer.

 

[MaverickDragon]

A tachometer on a hybrid is just a bit more useful than a bicycle for a fish...
It's not like you can shift it.
On an EB, it is more handy.

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