It Makes Sense that Start-Stop Engines Need a Higher Grade Oil

[CarbonSteel]

Exactly. Drop a load and then fly off.

Though, perhaps, not as entertaining as the 0W-8 thread(s)

 

[DavidJones]

I wonder if those with stop/start are able to get more than 2-3yrs from their big expensive batteries?

My big expensive battery is not quite 6 years old and has 97,000 miles on it. The system monitors the battery and won't allow the ASS to function if the battery is deemed low. According to the trucks "brain", my battery is still good. Initially, I didn't care much for the ASS system, now, I don't even think about it and I let it do it's thing.

 

[The Critic]

BMW does use a special coating on the bearings or crank (can't remember) with the move to 20w.

Probably iROX.

Federal Mogul's Innovative IROX(TM) Bearing Shell Design Enables Fuel Economy and CO2 Reduction by Increasing Reliability of High-Output, Hybrid and Stop-Start Engines

/PRNewswire-FirstCall/ -- Federal-Mogul Corporation (Nasdaq: FDML) has expanded the performance capabilities of engine bearings by developing an innovative...

www.prnewswire.com

 

[The Critic]

The RAM system is a bit different that a traditional start/stop system (like the one in my 2019 Wrangler), whereas the RAM version is a hybrid type with a 48 volt motor generator that provides about 90 lb-ft of torque to the crankshaft which is why those systems are so smooth from a stop versus the traditional ESS where the engine has to start before the vehicle will move. Later models (either 2020 or 2021) Wranglers have the 48v system on some engine options.

The traditional system on my Wrangler has a laundry list of conditions that have to be met (or not exist) before ESS will engage. One of the easiest ways to know the auxiliary battery is failing on a Wrangler is the start/stop system stops working.

I do not disagree that the two systems are different, but my original point still stands: the system allows for ESS events when the engine oil is cold. The engine oil was at 91F yesterday when the second start/stop event occurred.

 

[CarbonSteel]

I do not disagree that the two systems are different, but my original point still stands: the system allows for ESS events when the engine oil is cold. The engine oil was at 91F yesterday when the second start/stop event occurred.

That condition has to be unique to the 48V version because my Wrangler and Grand Cherokee will not engage ESS until the engine reaches operating temperatures.

 

[The Critic]

That condition has to be unique to the 48V version because my Wrangler and Grand Cherokee will not engage ESS until the engine reaches operating temperatures.

I was unable to find the parameters of the "calibrated threshold," but outside ambient was under 60F. Maybe even under 50F.

 

[The Critic]

That condition has to be unique to the 48V version because my Wrangler and Grand Cherokee will not engage ESS until the engine reaches operating temperatures.

Just an example. This was the first start/stop event of the day - about 3 minutes after a cold start-up. Note the oil temperature.

 

[CarbonSteel]

Just an example. This was the first start/stop event of the day - about 3 minutes after a cold start-up. Note the oil temperature.

View attachment 126187

I do not doubt what you are saying (or said), but the 48v system is not like a traditional ESS and the load at take-off is less on the engine versus that of traditional ESS which is "all engine".

For example, applying 90lb-ft of torque via the 48v system leaving a red light or stop sign is 40% of the available torque my 3.6L produces up to 1600RPM. Ergo, the 48v system is definitely putting less strain on the engine and in your photo an oil temperature of 91°F is not what I would consider cold--there is zero winter rating taking effect there and the oil is easily flowing to all parts of the engine.

 

[AEHaas]

"91°F is not what I would consider cold--there is zero winter rating taking effect there and the oil is easily flowing to all parts of the engine."

And if I remember correctly the Ferrari 812 Superfast will not allow for full RPM below 150F. It seems they feel differently about where the viscosity is appropriate for engine lubrication and protection.

Ali

 

[CarbonSteel]

"91°F is not what I would consider cold--there is zero winter rating taking effect there and the oil is easily flowing to all parts of the engine."

And if I remember correctly the Ferrari 812 Superfast will not allow for full RPM below 150F. It seems they feel differently about where the viscosity is appropriate for engine lubrication and protection.

Ali

You are comparing apples and swordfish. A RAM truck would hardly see full RPM from a red light or stop sign under normal operating conditions--and neither would a Ferrari (unless they were flashing their ego in an attempt to impress someone).

Are you somehow suggesting that at 91°F that oil is not flowing to all parts of the engine and that it requires another 60°F to do so?

 

[The Critic]

I do not doubt what you are saying (or said), but the 48v system is not like a traditional ESS and the load at take-off is less on the engine versus that of traditional ESS which is "all engine".

For example, applying 90lb-ft of torque via the 48v system leaving a red light or stop sign is 40% of the available torque my 3.6L produces up to 1600RPM. Ergo, the 48v system is definitely putting less strain on the engine and in your photo an oil temperature of 91°F is not what I would consider cold--there is zero winter rating taking effect there and the oil is easily flowing to all parts of the engine.

If I am understanding your correctly, you are proposing that eTorque allows for a slower "ramp-up" of engine speed (and load), so the parameters for allowing ESS operation can be more relaxed. I can understand your position.

My only concern with the approach is that eTorque only provides torque for a split second - the engine restart is almost instantaneous. So, I don't know how much eTorque is really helping from an initial load-reduction standpoint.

 

[CarbonSteel]

If I am understanding your correctly, you are proposing that eTorque allows for a slower "ramp-up" of engine speed (and load), so the parameters for allowing ESS operation can be more relaxed. I can understand your position.

My only concern with the approach is that eTorque only provides torque for a split second - the engine restart is almost instantaneous. So, I don't know how much eTorque is really helping from an initial load-reduction standpoint.

Yeah, not sure myself how long etorque is applied after restart but as it is a mild hybrid design, I am guessing it is longer than just engine restart.

 

[AEHaas]

'Just to be different I put Redline 0W-5 oil in the Lincoln Navigator this past weekend. I usually turn the Start/Stop off anyway but we shall see what happens.

Ali

 

[Bullwinkle007]

The oil life maintenance minder on my Pilot has always shown around 9000-10000 miles per 100% oil life. Usually about 1000 miles per 10% so changing at 5000 miles I have always been between 50%-60% oil life remaining according to the MM. Other owners have seen around 500 miles per 10% so it does vary per vehicle and conditions driven. I do about 70% city driving.

That's the same for my 2015 Acura MDX except for the winter. I have to work in Tahoe in the winter. The car is outside 24/7 there. When starting work or getting off work, it sees a lot of idle time. The maintenance minder cuts itself in half. 500 miles is 10% with seeing an HR day idle time.

 

[Bullwinkle007]

I guess I will never own a new car. Am I 2012 Accord does not have the system neither does my 2015 Acura MDX. It all started in 2016 on this model I guess I'll never own one. Seems like a maintenance headache when this crap breaks or leaves you stranded. These manufacturers are all following cafe trying to save 1% just like race cars are trying to find that 1% in horsepower gain. They just cannot leave crap alone. How about we just leave the engines alone they're already making plenty of power The technology is great how about invest that time and effort and cost and use much more carbon fiber it's lighter it's stronger it's a vehicles lighter than it's going to get better fuel economy. I had a 1991 Honda Civic hatchback DX 5-speed manual with the AC on at 80 85 mph it would achieve 42 mi per gallon. These vehicles nowadays are heavier. Lighten these vehicles up with carbon fiber, you will see better feeling economy