2024 Ram 1500 High RPM's on highway at low speed

[jovtra]

Just picked up 2024 Ram 1500 e torque sport. currently 400km on it. On my first drive on the hwy i got arround 15L per 100km average fuel economy, somewhat normal driving (10.5Lper 100km as per Factory). Sims to run on higher rpms, little over 2000 on speed of 100km/h .i drove 2023 classic before and the rpms where around 1500. Any suggestions?

 

[BossHogg]

Just picked up 2024 Ram 1500 e torque sport. currently 400km on it. On my first drive on the hwy i got arround 15L per 100km average fuel economy, somewhat normal driving (10.5Lper 100km as per Factory). Sims to run on higher rpms, little over 2000 on speed of 100km/h .i drove 2023 classic before and the rpms where around 1500. Any suggestions?

Some quick math indicates your transmission may be in 7th gear if your axel ratios are 3:92s and in 6th gear if your axel ratio is 3:21s. What gear was your transmission in when you observed this?

 

[jovtra]

thanks for your reply. it was in 8th gear.

 

[Wild one]

thanks for your reply. it was in 8th gear.

I'm guessing the Classic had 3.21 gears,and this truck has 3.92 gears. 3.92's are roughly 22% deeper,so you'll notice approximately 22% more rpm on the tach,or roughly 350 more rpm at 100 clics

 

[DanAR]

Isn’t 100 km/hr equal to 62 mph? And you are running 2000 rpm’s at that? My 2023 with the 3.92 axel registers pretty much on 2000 rpm’s at 70 mph. Sounds like your truck has a 4.10 gear (not available from factory that I’m aware of?) or as noted above is running in 7th.

Or your speedometer is not calibrated right.

 

[Wild one]

I wouldn't really call the tachs in the trucks precision instruments,they can have a bit of a varience.

 

[jovtra]

I'm guessing the Classic had 3.21 gears,and this truck has 3.92 gears. 3.92's are roughly 22% deeper,so you'll notice approximately 22% more rpm on the tach,or roughly 350 more rpm at 100 clics

There is possibility, if true makes since, but still the average gas mileage sims to high, close to 50 % more than manufacturer stated

 

[crash68]

There is possibility, if true makes since, but still the average gas mileage sims to high, close to 50 % more than manufacturer stated

The dash fuel economy indicator not very accurate, only for sure way to know accurate fuel economy is to hand calculate.
As for the rpms, either you weren't in 8th gear or you were going faster than 100 km/h. In this aspect mathematics can bee use to determine speed/gear ratios.

 

[crash68]

I wouldn't really call the tachs in the trucks precision instruments,they can have a bit of a varience.

If you pull the rpm data from the ECM using something like the Torque App, you can see the needle deflection can be off. Same goes for the speedometer.

 

[Wild one]

If you pull the rpm data from the ECM using something like the Torque App, you can see the needle deflection can be off. Same goes for the speedometer.

The tach in both the truck and 300 never really match what my old Diablo shows for rpm,the tach in both bounces around a fair bit compared to what the Diablo says.