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    GM to Offer Stop-Start on Most of Their Lineup By 2020


    • Your future GM vehicle will likely have a Stop-Start system

    General Motors is planning to expand the use of start-stop systems across most of their range by 2020 in an effort to improve fleetwide fuel economy. The plan will see at one powertrain combination offered in a vehicle to have this system. Stop-start systems work by turning off the engine when the vehicle isn't moving. When the driver removes his/her foot from the brake, the engine will kick back on.

     

    This move comes as the EPA will start handing out credits towards compliance with corporate average fuel economy standards to automakers who use this system in their vehicles next year.

     

    "Everyone will end up adding start-stop. Now there's a benefit in the EPA cycle, which there wasn't a few years ago. GM's new nine- and 10-speed automatic transmissions have been engineered from the beginning to incorporate start-stop. That will make it much easier and much smoother. That's what's been the holdup. First it was a regulatory issue, then it was a hardware issue," said AutoPacific analyst Dave Sullivan.

     

    GM spokesman Tom Read tells Automotive News that vehicles equipped with the stop-start system will use absorbent glass mat batteries (AGM) and tandem solenoid starters to enable faster and smoother restarts.

     

    Source: Automotive News (Subscription Required)

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    a friend took me in his 14 malibu for a ride and it had start stop......worked pretty well.  

     

    All that said, I WANT A SWITCH TO TURN IT OFF IF I WANT.....

     

    reasons- 

     

    winter (i don't care that it turns itself off at a certain temp)

    when your car ages and may have trouble running, why would you want something that deliberately shuts off the car

    continual stop and start is hard on vehicle components and fluids, turning off start stop would reduce wear

     

    Not being able to turn off the start / stop = federal overreach

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    Your final point about reducing wear is exactly backwards and out of date. The GM system keeps the oil pressurized, The engine fires nearly instantly with direct injection, and in the case of the BAS system, the regular starter is not used.

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    Wonder how well it will hold up over time...

     

    Thinking it should last 200k like the rest of the car....

     

    In the eAssist systems, it's just a giant alternator that can also be a 15 horsepower electric motor, attached to the crank pulley via a thicker than normal serpentine belt.  The technical difference is so minor..... it's nothing to worry about.  The current start/stop system is just the old eAssist system with a smaller battery and smaller alternator/motor which doesn't assist the engine during acceleration.

     

    Given all of GM's other troubles over the past 10 years, the fact that we've heard basically nothing bad about the reliability of eAssist should tell us something. 

     

    That said... this announcement sounds like a different setup than the eAssist in that it runs through the transmission instead, making it more of a traditional starter.

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    Your final point about reducing wear is exactly backwards and out of date. The GM system keeps the oil pressurized, The engine fires nearly instantly with direct injection, and in the case of the BAS system, the regular starter is not used.

    That is very good to know.

     

    Although I would still appreciate a switch to be able to turn it off. And if the system is as seamless as they make it sound, then I'll never turn it off. 

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    Your final point about reducing wear is exactly backwards and out of date. The GM system keeps the oil pressurized, The engine fires nearly instantly with direct injection, and in the case of the BAS system, the regular starter is not used.

    That is very good to know.

     

    Although I would still appreciate a switch to be able to turn it off. And if the system is as seamless as they make it sound, then I'll never turn it off. 

     

     

    It takes about half a day to get used to it.... and that was even on the jittery Benz version.

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    Your final point about reducing wear is exactly backwards and out of date. The GM system keeps the oil pressurized, The engine fires nearly instantly with direct injection, and in the case of the BAS system, the regular starter is not used.

    That is very good to know.

     

    Although I would still appreciate a switch to be able to turn it off. And if the system is as seamless as they make it sound, then I'll never turn it off. 

     

    same here, it should be user control.

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    Let me make this clear from the start I am not a fan of the start stop.  I too wish for a delete button. 

     

    Now let me get to the truth about the system. GM has one of if not the best system out there. It is smooth and is pretty much not noticeable unless you really are looking for it. [Even I have to admit my reluctance is petty] 

     

    The cars today get up to temp in the matter of a mile or so and will get to temp even faster moving ahead. Fast warm up is key to lower emissions and that is a focus of all companies. 

     

    The system has proven durable in the older cars and trucks with it. While rare they have not seen any major issues. 

    Wear is a falsehood by those who really are not up on the system or systems out today. 

    The delete button is much like the Skip shift. It has to be on full time to be considered by the EPA to get the MPG listed. Now with that said I would not be shocked if Jet or Hypertech may make a OBDII plug in that may defeat the shut down if you so choose. GM will not fight them on it in the aftermarket. 

     

    The only real negative is if something does go out it could be a bit pricey to replace but on today's cars most things are pricey. But even then how often have you had to replace a starter lately. I have had going on 30 cars over the years and only had two go out on late 68 and 70 Chevy. 

    It has gotten to the point where cars may run longer but when they do wear parts out their worth is less than the value of a change of a cam belt or other mechanical issue anymore. I suspect the used car market may be in for some changes with high mileage hybrids and higher tech cars in need of repair. 

     

    Many will be parted out and may lead to even more salvage parts being sold by dismantlers.

     

    As for the stop start it is seen where most companies will have it on 75% or more of their cars from most MFG. The deal is you are going to get it no matter if you like it or not.  

     

    At some point these will become the norm and we may notice more the cars that do not shut off than the ones that do. 

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    Wonder how well it will hold up over time...

     

    Thinking it should last 200k like the rest of the car....

     

    In the eAssist systems, it's just a giant alternator that can also be a 15 horsepower electric motor, attached to the crank pulley via a thicker than normal serpentine belt.  The technical difference is so minor..... it's nothing to worry about.  The current start/stop system is just the old eAssist system with a smaller battery and smaller alternator/motor which doesn't assist the engine during acceleration.

     

    Given all of GM's other troubles over the past 10 years, the fact that we've heard basically nothing bad about the reliability of eAssist should tell us something. 

     

    That said... this announcement sounds like a different setup than the eAssist in that it runs through the transmission instead, making it more of a traditional starter.

     

     

     

    Yeah, kinda what I figure as well. GM does not always tend to be on the forefront of stuff, but tends to make sure it is right and solid when it comes out....

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    Let me make this clear from the start I am not a fan of the start stop.  I too wish for a delete button. 

     

    Now let me get to the truth about the system. GM has one of if not the best system out there. It is smooth and is pretty much not noticeable unless you really are looking for it. [Even I have to admit my reluctance is petty] 

     

    The cars today get up to temp in the matter of a mile or so and will get to temp even faster moving ahead. Fast warm up is key to lower emissions and that is a focus of all companies. 

     

    The system has proven durable in the older cars and trucks with it. While rare they have not seen any major issues. 

    Wear is a falsehood by those who really are not up on the system or systems out today. 

    The delete button is much like the Skip shift. It has to be on full time to be considered by the EPA to get the MPG listed. Now with that said I would not be shocked if Jet or Hypertech may make a OBDII plug in that may defeat the shut down if you so choose. GM will not fight them on it in the aftermarket. 

     

    The only real negative is if something does go out it could be a bit pricey to replace but on today's cars most things are pricey. But even then how often have you had to replace a starter lately. I have had going on 30 cars over the years and only had two go out on late 68 and 70 Chevy. 

    It has gotten to the point where cars may run longer but when they do wear parts out their worth is less than the value of a change of a cam belt or other mechanical issue anymore. I suspect the used car market may be in for some changes with high mileage hybrids and higher tech cars in need of repair. 

     

    Many will be parted out and may lead to even more salvage parts being sold by dismantlers.

     

    As for the stop start it is seen where most companies will have it on 75% or more of their cars from most MFG. The deal is you are going to get it no matter if you like it or not.  

     

    At some point these will become the norm and we may notice more the cars that do not shut off than the ones that do. 

    yup, and despite all that, like a traction control switch, it still would be desired to have the control to turn it off.

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    I am so glad the 2016 Spark has a switch to turn off the traction control to enable more epic burnouts and a better chance of continued forward motion in deep snow, sand or mud.

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    I would definitely weigh it as a negative in any future purchase.

     

    Well by then it will be like Seat Belts as you may not have many options otherwise.  

     

    This is an industry wide deal and it is going to be found nearly everywhere. 

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    I would definitely weigh it as a negative in any future purchase.

     

    Well by then it will be like Seat Belts as you may not have many options otherwise.  

     

    This is an industry wide deal and it is going to be found nearly everywhere. 

     

    And seat belts can be worn or not worn. ;) (legal ramifications are another story) 

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    I would definitely weigh it as a negative in any future purchase.

     

    Well by then it will be like Seat Belts as you may not have many options otherwise.  

     

    This is an industry wide deal and it is going to be found nearly everywhere. 

     

    And seat belts can be worn or not worn. ;) (legal ramifications are another story) 

     

     

     

    The bottom line is legally they will have to have it with no defeat switch to count as a EPA boost to MPG. 

     

    No different than the skip shift on the Vette. 

     

    Now I can see a plug in for the OBDII that could disable it. The after market will provide what the MFG can not do. 

     

    In other words don't get worked up over it as there will be a work around. Besides by the time you buy one they may be very common and well sorted. I hate it too but I have seen these dilemmas come and go many times. 

    Good god the people got their panties in a wad over cars with Fuel Injection when it came out. It was Oh my god we will never be able to modify them again. Well Look around now. 

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    I hope there is an off switch as well.

     

    These are good for time you sit a long time at a red light, or sit in a fast food drive through or something like that when you are doing mostly sitting.  But they they start shutting the ending off for 2 seconds at a stop sign they get annoying.

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    I had a '16 Malibu in Ohio last week, the start/stop was pretty smooth and unobtrusive.   Though in really hot weather it would be annoying to have the A/C cut in and out. 

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    I had a '16 Malibu in Ohio last week, the start/stop was pretty smooth and unobtrusive.   Though in really hot weather it would be annoying to have the A/C cut in and out. 

     

    On the Malibu, if you set the AC to Max, the Start/Stop will be minimized

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    I had a '16 Malibu in Ohio last week, the start/stop was pretty smooth and unobtrusive.   Though in really hot weather it would be annoying to have the A/C cut in and out.

     

    On the Malibu, if you set the AC to Max, the Start/Stop will be minimized

    Good to know. I was never able to shut off the ventilation completely. I could set it to floor or dash vents or both, but never neither. But that's another issue...

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    The AC in the stop starts I have been in never were an issue. The only real noticeable thing was the tach dropping and a little jump on start up that is no longer an issue. 

    The first one I drove on a truck I was expecting it to feel like the car stalled and it never did. That was long ago too and the newer systems are much better and only getting better. 

    Like I said I am not a fan but I can not bad mouth it because it does work. 

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      Segment firsts
      Re-melt piston bowl rim Venturi Jet Drain Oil Separator Closed-loop glow plug temperature control Stronger pistons with remelt
      A tough, forged micro-alloy steel crankshaft anchors the new Duramax’s stronger rotating assembly. Cut-then-rolled journal fillets contribute to its durability by strengthening the junction where the journals — the round sections on which the bearings slide — meet the webs that separate the main and rod journals.
      The connecting rods are stronger, too, and incorporate a new 45-degree split-angle design to allow the larger-diameter rod bearings to pass through the cylinder bores during engine assembly. They’re forged and sintered with a durable powdered metal alloy, with a fractured-cap design enabling more precise cap-to-rod fitment. 
      A new, stronger cast-aluminum piston design tops off the rotating assembly. It features a taller crown area and a remelted combustion bowl rim for greater strength. Remelting is an additional manufacturing process for aluminum pistons in which the bowl rim area is reheated after casting and pre-machining, creating a much finer and more consistent metal grain structure that greatly enhances thermal fatigue properties.
      Additionally, the Duramax’s pistons don’t use pin bushings, reducing reciprocating weight to help the engine rev quicker and respond faster to throttle changes.
      Lightweight cylinder heads, solenoid injectors
      The redesigned engine retains the Duramax’s signature first-in-class aluminum cylinder head design, with six head bolts per cylinder and four valves per cylinder. The aluminum construction helps reduce the engine’s overall weight, while the six-bolt design provides exceptional head-clamping strength — a must in a high-compression, turbocharged application.
      A new aluminum head casting uses a new double-layer water core design that separates and arranges water cores in layers to create a stiffer head structure with more precise coolant flow control. The heads’ airflow passages are also heavily revised to enhance airflow, contributing to the engine’s increased horsepower and torque.
      The Duramax employs a common-rail direct injection fuel system with new high-capability solenoid-type injectors. High fuel pressure of 29,000 psi (2,000 bar) promotes excellent fuel atomization for a cleaner burn that promotes reduced particulate emissions. The new injectors also support up to seven fuel delivery events per combustion event, contributing to lower noise, greater efficiency and lower emissions. Technology advancements enable less-complex solenoid injectors to deliver comparable performance to piezo-type injectors.
      Electronically controlled, variable-geometry turbocharging system
      A new electronically controlled, variable-vane turbocharger advances the Duramax’s legacy of variable-geometry boosting. Compared to the current engine, the system produces higher maximum boost pressure — 28 psi (195 kPa) — to help the engine make more power, and revisions to enhance the capability of the exhaust-brake system.
      Along with a new camshaft profile and improved cylinder head design, the Duramax’s new variable-vane turbocharger enables the engine to deliver more power with lower exhaust emissions. It uses a more advanced variable-vane mechanism, allowing a 104-degree F (40 C) increase in exhaust temperature capability. The self-contained mechanism decouples movement from the turbine housing, allowing operation at higher temperature. That enables the engine to achieve higher power at lower cylinder pressure. Additionally, it has lower internal leakage, allowing more exhaust energy to be captured during exhaust braking.
      The integrated exhaust brake system makes towing less stressful by creating added backpressure in the exhaust, resulting in negative torque during deceleration and downhill driving, enhancing driver control and prolonging brake pad life.
      Venturi Jet Drain Oil Separator
      A new Venturi Jet Drain Oil Separator employed with the Duramax 6.6L is the first of its type in the segment and is designed to ensure oil control in sustained full-load operation. The totally sealed system collects the fine mist of oil entrained in the blow-by gas and uses a small portion of the boosted air generated by the turbocharger to pump the collected oil back to the engine oil sump for re-use by the engine. Less sophisticated systems are not able to return this oil during full-load operation, which can result in oil carryover into the cylinders during combustion.
      Cold Start System
      The new Duramax also provides outstanding cold-weather performance, with microprocessor-controlled glow plugs capable of gas-engine-like starting performance in fewer than 3 seconds in temperatures as low as -20 degrees F (-29 C) without a block heater. The system is enhanced with ceramic glow plugs and automatic temperature compensation — a first-in-class feature providing improved robustness and capability. The automatic temperature compensation assesses and adjusts the current to each glow plug for every use, providing optimal temperature for cold start performance and durability.     
      Electronic throttle valve and cooled EGR
      Unlike a gasoline engine, a diesel engine doesn’t necessarily require a throttle control system. The Duramax 6.6L employs an electronic throttle valve to regulate intake manifold pressure in order to increase exhaust gas recirculation (EGR) rates. It also contributes to smoother engine shutdown.
      Additionally, a cooled exhaust gas recirculation (EGR) system enhances performance and helps reduce emissions by diverting some of the engine-out exhaust gas and mixing it back into the fresh intake air stream, which is fed through the cylinder head for combustion. This lowers combustion temperatures, improving emissions performance by reducing NOx formation.
      The exhaust is cooled in a unique heat exchanger before it’s fed into the intake stream through a patented EGR mixing device, further improving emissions and performance capability. An integrated bypass allows non-cooled exhaust gas to be fed back into the system to help the engine more quickly achieve optimal operating temperature when cold.
      B20 Biodiesel Capability
      The new Duramax 6.6L is capable of running on B20 biodiesel, a fuel composed of 20 percent biodiesel and 80 percent conventional diesel. B20 helps lower carbon dioxide emissions and lessens dependence on petroleum. It is a domestically produced, renewable fuel made primarily of plant matter — mostly soybean oil.
      Manufacturing
      The new Duramax 6.6L turbo-diesel engine is produced with locally and globally sourced parts at the DMAX Ltd. (GM’s joint venture with Isuzu) manufacturing facility in Moraine, Ohio.
      Allison 1000 Automatic Transmission
      The proven Allison 1000 six-speed automatic transmission is matched with the new Duramax 6.6L. A number of refinements have been made to accommodate the engine’s higher torque capacity, including a new torque converter.
      The Allison 1000’s technologically advanced control features, such as driver shift control with manual shift feature and a patented elevated idle mode cab warm-up feature, haven’t changed. Also, the Tow/Haul mode reduces shift cycling for better control and improved cooling when towing or hauling heavy loads.
      There’s also a smart diesel exhaust brake feature that enhances control when descending steep grades.
    • By William Maley
      The seemingly never-ending diesel heavy-duty truck war is back in force with Ford announcing the power figures for the F-Series Super Duty back in the summer. We were wondering when either FCA or GM would strike back. Well GM did this over the weekend by accidently and then subsequently deleting the figures for the next-generation Duramax V8 diesel.
      Truck Trend got screenshots of GM Powertrain's website where the details of the L5P 6.6L Duramax turbodiesel are there to see: 445 horsepower and 910 pound-feet of torque. Compared the 6.7L PowerStoke V8 found in the 2017 F-Series Super Duty, the updated Duramax produces 5 more horsepower but is slight behind in torque (15 down from the PowerStroke's 925 pound-feet).
      We know for sure that the new Duramax will debut a new air intake system (you can see the new hood scoop in the picture above). More air is a good thing as it means better cooling and more power.
      The Texas State Fair is this week and it has become a showplace for the various truck manufacturers to make big announcements. We wouldn't be shocked if General Motors debuts the new Duramax there.
      Source: Truck Trend

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