Stop / Start

[IvoryHemi]

Isn't one of the advantages of the eTorque system is that it adds low-end torque? I can't be sure, but I seem to recall reading that somewhere. If that's true, then the torque added to the engine by the eTorque system could what helps the engine stay in ECO at lower speeds.

Just my $0.02 (before tax). YMMV.

Max output is 130 lb-ft off idle. It’s output drops off as engine RPM increases. BSG spins approx 2.5 times per crankshaft rotation to get there. Basically the engine output becomes greater than the electric assist. I recall reading over ~1500 rpm output is zero

So below that you’ll get a boost, over ~1,500 rpm is all Hemi

Which is why most people can’t feel a difference because it’s operating range is so small

 

[834k3r]

“The Hemi's eTorque motor is good for 16 horses and 49 lb-ft and, again, multiplied through a slightly different ratio for an assist of 130 lb-ft.

Thanks--I obviously didn't read the article.

 

[brian42]

“that box” that replaces the alternator is called the Brake Start Generator (BSG).

It essentially gives the engine a “slight tug” to aid in smoother starting. This is in combination with a traditional starter

I did not know that.

I learned 2 new things today! (I now know what BSG stands for too )

 

[piening2150]

“that box” that replaces the alternator is called the Brake Start Generator (BSG).

It essentially gives the engine a “slight tug” to aid in smoother starting. This is in combination with a traditional starter

I didn't think the traditional starter did anything on ET restarts. The 'slight tug' from the BSG rolls it over enough to get the engine refired quickly on its own. Like popping the clutch on a manual car when the battery dies or starter fails. Definitely an audible difference between starting with the push button/remote start and the ET restart from a stop. Much faster too.

 

[IvoryHemi]

I didn't think the traditional starter did anything on ET restarts. The 'slight tug' from the BSG rolls it over enough to get the engine refired quickly on its own. Like popping the clutch on a manual car when the battery dies or starter fails. Definitely an audible difference between starting with the push button/remote start and the ET restart from a stop. Much faster too.

BSG cannot start the engine on its own.

The audible difference/speed is because BSG doesn’t aid dead starts, it only assists with ESS

 

[mikeru82]

BSG cannot start the engine on its own.

The audible difference/speed is because BSG doesn’t aid dead starts, it only assists with ESS

Articles I've read and videos I've watched specifically stated that the generator/motor is what restarts the engine during stop/start operation, not the traditional starter. And the traditional starter is only used when starting the truck with the button or remote starting. The whole reason it restarts so fast is because there is no delay for the starter solenoid to kick out the starter gear.

 

[Neurobit]

“The Hemi's eTorque motor is good for 16 horses and 49 lb-ft and, again, multiplied through a slightly different ratio for an assist of 130 lb-ft.”

This only happens the first half rotation of the wheels to assist with a smooth start before the vehicle transitions from the electric motor to the Hemi. MDS will never activate during this phase. Your service manager doesn't know what he's talking about.

 

[brian42]

I think you have to be at least 15 or 20 mph before MDS will activate.

I know coming up to a stoplight my MDS turns off at 20 or 15 mph (don't remember which).

 

[SpeedyV]

I think you have to be at least 15 or 20 mph before MDS will activate.

I know coming up to a stoplight my MDS turns off at 20 or 15 mph (don't remember which).

I want to say that it's a function of engine load, not speed. I slow down for a gradual turn and climb a gentle hill at low speed into my neighborhood, and sometimes MDS remains engaged the whole time (usually popping out a few seconds into the hill).

 

[NorthStar]

This only happens the first half rotation of the wheels to assist with a smooth start before the vehicle transitions from the electric motor to the Hemi. MDS will never activate during this phase. Your service manager doesn't know what he's talking about.

I regret to inform you, Sir, that yer full of crap.

Every Ram owner knows the FCA Service Managers are the most honest, trustworthy and faithful of any person you’ll ever meet. Most of us name our first born after them, wait by the phone for stock market advice from them and know every one of them in the U.S. can be trusted with our most precious possessions.

 

[theblet]

Articles I've read and videos I've watched specifically stated that the generator/motor is what restarts the engine during stop/start operation, not the traditional starter. And the traditional starter is only used when starting the truck with the button or remote starting. The whole reason it restarts so fast is because there is no delay for the starter solenoid to kick out the starter gear.

I understood the same thing. I don’t have ET but the ones I test drove have the smoothest stop/start on the market.

 

[Neurobit]

I want to say that it's a function of engine load, not speed. I slow down for a gradual turn and climb a gentle hill at low speed into my neighborhood, and sometimes MDS remains engaged the whole time (usually popping out a few seconds into the hill).

Speedy,

I'd have to say it's prob a combination of both. If you're coasting along, and let the truck slow down to a stop, your MDS light will shut off at 15MPH without any load. Just confirmed it this morning.
If it were just load-based, the light would stay on while cruising at 15MPH or less.

Cheers,

 

[SpeedyV]

Speedy,

I'd have to say it's prob a combination of both. If you're coasting along, and let the truck slow down to a stop, your MDS light will shut off at 15MPH without any load. Just confirmed it this morning.
If it were just load-based, the light would stay on while cruising at 15MPH or less.

Cheers,

You're probably right about the "no load" condition. I think you have to be slightly on the throttle. I'll have to see if I can keep it engaged, but I know I've had it on below 15 mph (unless I'm turning a corner and heading uphill faster than I think).

 

[silver billet]

MDS shuts off for me like clockwork, everytime below a certain speed (about 24 km/h). Doesn't matter if you're coasting to a stop or mild acceleration, it is never on for me below that speed. Possibly etorque models are different?

 

[SpeedyV]

MDS shuts off for me like clockwork, everytime below a certain speed (about 24 km/h). Doesn't matter if you're coasting to a stop or mild acceleration, it is never on for me below that speed. Possibly etorque models are different?

Could be. One of the stated goals of eTorque was to keep MDS engaged longer. Hadn't thought about that applying to low-speed operation. Again, I'll need to be more scientific about testing this before drawing conclusions.

 

[JF19Longhorn]

The Etrq does not use the starter when AS/S restarts the truck. The only time the start is used is when you press the 'Run' button or use your remote to start the truck.

 

[SpeedyV]

The Etrq does not use the starter when AS/S restarts the truck. The only time the start is used is when you press the 'Run' button or use your remote to start the truck.

Yep...hence "BSG" or "belt-driven starter generator"!

 

[Amerinamese]

Speedy,

I'd have to say it's prob a combination of both. If you're coasting along, and let the truck slow down to a stop, your MDS light will shut off at 15MPH without any load. Just confirmed it this morning.
If it were just load-based, the light would stay on while cruising at 15MPH or less.

Cheers,

It's in the manual. I don't have it on me at the moment so I don't know it verbatim, but I seem to remember it saying that there has to be less than 25% load for 4 seconds for MDS to kick in. It turns off if there is more than 50% load put on the throttle or if the RPMs drop below 1500.

 

[brian42]

There's no mention of MDS in any of the manuals for the truck which is probably why there's differing viewpoints. The closest mention of MDS in the Owner's Manual and User Guide:

ECO Mode Indicator Light - This light will turn on when ECO Mode is active.

If anyone is curious there's no mention of MDS or ECO Mode in the Radio Guide.

Everything I can Google tells me how it works, not when it works (what conditions will activate/deactivate/inhibit). We all know that selecting a max gear or using Tow/Haul will disable it but the actual parameters for the truck to turn on/off MDS seem to be a mystery with plenty of speculation.

 

[Jeremy1974]

Hate to resurrect this post, but... How does the Auto Start/Stop feature work in a 2020 Ram 1500 5.7 Hemi that is NOT equipped with an eTorque system? I ask because I ran across a truck that has just that set up...