Towing 3rd Gen

Load is a big factor and duty cycle of the injector.

 

More fuel injected per stroke?

 

My take, the RAM did pretty good, it has less torque and is a natural aspirated engine so, it was loosing power (3% per 1000 ft) as it was climbing.

 

But not compared to the tundra

 

But didn’t they specifically say they were slowed down by slow moving vehicles? This whole test seems wack.

 

Ya the tundra towed better and clearly is more capable but it lost because the host is tall and the bigger guy can’t handle the tow hook thing lol.

 

List on most people the tow test was up a very steep mountain pass that sucks fuel. They will do a 50 or 100 mile flat tow loop that will give actual towing MPG.

 

Nahh it will be the Denali or at4 ultimate or zr2 off-road

 

Gonna need some Tequila for all this salt in here.

 

I just watched the video, seemed like the tundra easily went up the hill like no big deal, ram was reving like crazy.

tow test = tundra easy in that comparison.

I wonder how tow haul + setting would have been if they used it for the engine braking

 

I watched most of it, but did he ever disclose what the computer said for MPG's on either truck?

 

Nope, nothing relevant, like weight etc. However, what I have noticed in all of the videos I have seen, the oil pressure gauge of the engine always reading low

 

New video. #2

https://youtu.be/I4g4t94wgvM

 

What was the new outcome?

 

Better mileage in tow + but that’s about all it changed. And oddly didn’t down shift as far going downhill.

 

If you’re thinking of it as a comparison of two similar engines I can see that.

These are not two similar engines, one is naturally aspirated and the other is turbocharged.

The naturally aspirated engine draws in air at atmospheric pressure, which is variable dependent on elevation. Temperature and humidity can also factor in to how much effective air density a naturally aspirated engine can inhale, but not nearly as much as the base atmospheric pressure at a given elevation.

Naturally aspirated engines will see a 3% loss in power output for every 1000ft of altitude gained. The Ike Gauntlet starts around 9,000ft and ends just over 11,000ft. So our Ram 5.7L HEMI rated for 395hp and 410ft-lbs at sea level is only making 288hp at the start, and 299ft-lbs of torque. By the time it gets up top it’s down to 265hp, and 275ft-lbs.

So the HEMI isn’t getting enough air to make full power, and will not burn as much fuel. Notice on the run up the hill the HEMI wanted to stick to that 4000 RPM range where peak torque is. That’s what it’s paired up with the gear ratios in that transmission to do. At that elevation making 299ft-lbs and spinning 4,000 RPM the Ram is making about 228hp for what it’s worth.

The new Tundra with that turbo 3.4L is a different animal. Turbos multiply atmospheric pressure by compressing inlet air and force feeding it into the intake manifold. Under full boost in the efficient range of the turbos given their size that 3.4L is performing like a much larger engine at sea level, and doing it all the time. Let’s say it gets enough boost to hit 1 Bar, that is effectively making it act like a 6.8L in the RPM range the turbos are efficient in. The turbos are sized for low RPM and midrange RPM power, and fall off at higher RPM being unable to move enough air to keep high manifold pressures as engine speeds get up north of 5K. At peak torque of 479ft-lbs at 2400 RPM to around 3000 RPM we observed the Tundra pull the hill at the engine is making 219hp- 274hp and the transmission is paired well to surf that low end power. Since it’s force fed the Tundra is making full power or damn close to it, and can burn more fuel. Plus turbocharged engines being worked are usually tuned to inject a bit more fuel because it acts to keep combustion chamber temps down and protect against knock.

Downhill performance surprised me, Tundra did better than I would have expected. Small displacement engines don’t have near the swept displacement to act as an engine brake as a big naturally aspirated V8. Turbos don’t do shit to enhance engine braking.

 

They went up and down in D, probably it it would of helped the downhill speed shifting to S. I do not know which S is 1 to 1 and which are the OD

 

In the 2022 Tundra 7th gear is 1.00:1, and 6th is 1.19:1.