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Hi All:

___I just received the opportunity to take a 2-Mode out for a few hours next Tuesday in Detroit. Is there any questions you may have wanted answered while I have the GM engineers and the vehicle at my disposal?

___Thanks in advance.

___Good Luck

___Wayne

yeah. ask them why they don't start pushing smaller vehicles. :mad:

Thats easy, they will say their customers don't want smaller vehicles.

Thats easy, they will say their customers don't want smaller vehicles.

somehow they convinced them they wanted larger ones....they should just use the same tactics in reverse....

The Japanese started doing that a long time ago. Japanese trucks got bigger, and so did Toyota.

Yes. Ask them why their first hybrids were land yachts instead of reasonable cars.

Then ask them why they wasted their time creating the worlds most laughable and least beneficial hybrid system.

Then ask them why it costs so much but does so little when Toyota and Honda never had a problem doing so much more for roughly the same cost.

Then ask them how far dumping off Stan Oshivsky's NiMH technology has pushed back both their hybrid and EV programs.

Then ask them why every major safety, mileage, emission and manufacturing innovation in the last 35 years has come from Japan instead of Detroit.

Here's some for you, Wayne:

If it can drive on electric alone, what are the speed/load restrictions?

How large is the battery pack and where is it located?

Can the vehicle accelerate from a stop without battery and on only 4 cylinders?

Does it use a standard starter or will it use the electric motor from the hybrid system to spin up the engine somehow?

Are there temperature controls that cut out use of the batteries when too hot/cold?

What are the warm up requirements for this system?

How much hp/torque is available from the electric motor? Weight of motor and battery system?

What is the extra weight associated with the 2 mode system as a whole?

Does the system require any special maintenance?

How much dashboard feedback/information can you get related to the use of the 2 mode system and the various states it uses?

Is the system configured such that an increased capacity battery will improve mileage?

Does the system use A123 tech, or will it in future?

Are there plans to scale this down to small passenger sized vehicles?

Is regenerative braking implemented like the Prius so that brake pads can be avoided completely for gradual stops?

How seamless are the transitions in state?

Does the system power most of the "normal" electrical systems of the car from the 12V? How big is the 12V?

Is the vehicle flex fuel? Are there any plans to introduce a diesel version?

Those are all the ones I can think of at the moment...

Towing capacity.

Hi Sean and FireNurse:

___The following should help a little? I hope to pick up more info tomorrow morning?

How large is the battery pack and where is it located?

___300V NiMH under the second-row seat.

Are there temperature controls that cut out use of the batteries when too hot/cold?

___Yes.

How much dashboard feedback/information can you get related to the use of the 2 mode system and the various states it uses?

___There is an energy display but I am not sure about any i and aFCD’s?

Is the system configured such that an increased capacity battery will improve mileage?

___Not under most circumstances. Even the Prius and FEH packs are oversized for most conditions to maximize FE.

Does the system use A123 tech, or will it in future?

___Not yet. When the Li-Ion’s are the same price as NiMH’s, they more then likely will given the power density and overall lighter weight.

Are there plans to scale this down to small passenger sized vehicles?

___The VUE receives a FWD 2-Mode late next year.

Does the system power most of the "normal" electrical systems of the car from the 12V? How big is the 12V?

___Pack vs. 12V supply: Most are 300V: 300-volt (transmission, air conditioning, heater pump, front crash sensor); 42-volt (power steering); 12-volt (vehicle accessories)

Towing capacity.

___The 2WD can tow 6,200 #’s while the 4WD can tow 6,000 #’s.

___Good Luck

___Wayne

What is the GVWR?

What is the GCVWR?

What is the curb weight?

Hi TheTonka:

___I will get you those numbers when I get back home but for now, this was a fun vehicle for its size. A ton of info but I do not think it was enough for a preview :( The Hybrid drive-train was a nice design for the first time out of the box but I wish I would have had the opportunity to bend their ear before the design specs were locked down.

___It appears Japan Inc. is going to have their way with GM on this one. The Ni-MH’s are PanasonicEV’s and small ones at that! The GM reps I spoke with today mentioned the pack cost > $2K on its own and with that high a cost for the pack, GM may never recover the design and engineering expense let alone the cost of producing a limited number of 2-Modes. The MSRP will be released at the LA Auto Show press event on the 14th w/ a ball park premium upwards of $5K. A healthy $3K + tax credit will probably be in the offing to help offset the premium but Toyota receives a larger pack from PanasonicEV, Aisin tranny and builds the inverter and MGSet’s in-house (possibly?) for less then just the smallish NiMH pack GM has to pay for! Something doesn’t smell right and it appears as if GM is getting the short end of the stick wrt this :ccry:

___This thing is one heavyweight SOB but low and behold, once the tires were pressed up to 41 #’s all around, she showed some stuff. Remember this thing is almost 6,000 #’s all by itself and she can EV up to as high as 26 mph (that I saw so far) before ICE-on occurs. Unfortunately, GM placed a hard ceiling on her EV mode at < 32 mph.

___Temps in the mid to upper 30’s and raining the entire time … Out on the highway in V4 mode, she will punch out 30 + mpg up to 55 + mph all day long! Around town, 25 is about all you are going to see to begin with. You cannot control the ICE-Off mode like you can with an FEH and especially an HSD equipped Toyota but in some cases, you do not have to. During rush hour in Detroit with stop light to stop light driving and maybe 5 – 7 miles of highway allowed a decent enough 29.6 mpg for my run. 24.6 with me helping Eddie, the Men’s Health Journal writer in stop light to stop light traffic stop and crawls. Some quirks wrt to ICE-On and Off modes of course but it is has imperceptibly smooth transitions from ICE-On to off and back on again as well as V4 to V8 and back transitions. D**n if GM did not build a better mouse trap with 2-Mode but with some programming mistakes. You cannot glide with the accelerator and N is a must. Shutting down the ICE is tough but not impossible. There is no SOC gauge so you are not sure where the pack sits with what you can and cannot do. However, start a Glide by shifting to N below 32 and she will Auto Stop even when moving about 80% of the time after maybe 3 or 4 seconds. I am not sure why the delay or the failures but that is just the way it was? I should have shoved her into a NICE-On at 55 and see if she would Auto Stop at that speed too? Controlling V4 or V8 operation at slow speeds was very tough in the stop and crawls. At highway speeds, V4 is easy to hold. V8 appeared sometime even when the ICE was unloaded when even 4 was not needed?

___Enough for now. 2.5 hours of sleep between leaving Minneapolis yesterday afternoon and arriving in Detroit this morning along with a few hours behind the wheel of the 2-Mode this afternoon is a but much and I am beat :( This thing will be fun for whoever gets a week to discover her secrets but being so cold in the North now, it will probably be a southern gentleman showing us the ropes?

___Good Luck

___Wayne

Sounds like it actually has some pretty decent performance for a big dog. Good to hear.

nice article on the two mode wayne, despite its bulkiness its the most efficient 8 seater so far, should load 8 seats and get 30 mpg, then that's something.

Always looking forward of the test drives of behind the world's most fuel efficient driver!

but having the engine killed when you shoved it into N, bravo GM you've seen the light!

Wayne, thanks for the great writeup. Impressive FE for such a large vehicle, darn near what I can get with my Subaru.

The plus side of this is that if 2-modes sell well, we'll actually save a lot more fuel than if the equivalent number of Priuses were sold. :cool:

The minus side is that if 2-modes sell well and discourage people from buying smaller vehicles, it's just that many more 6000 pound behemoths on the road to kill and maim the rest of us economy car drivers, pedestrians and cyclists. :mad:

Beyond that, question time. From what genuinely detailed information I've been able to glean about how this drivetrain works, it sounds like the major "improvement" is that the "mechanical" (if you can call a slushbox mechanical) path of the 4-speed AT at this system's heart is more efficient than the electric path used by the HSD system's MG1-planetary gear-MG2 connection. Some questions about this:

- How does the addition of electric motors to a 4sp AT achieve a CVT effect? It seems that unless you use an electric path between MG1 and MG2 (one in gen mode and one in motor mode) you're still going to be stuck with 4 fixed gear ratios. Does the system still use an electric path in this way, allowing the 4 different gears to provide 4 different gear ratios between MG1 and MG2, thus reducing the amount of energy that must flow through the electric path? Or are you in fact stuck with 4 fixed gear ratios? And if so, why would you need two motors?
- Under the "2mode" label, the abilities of the HSD system are considered one "mode" (which seems silly to me) and then the second "mode" allows the MG1 and MG2 to perform a different role under high speed and/or torque situations. Are both motors needed/used in this "mode"?
- Have you found a schematic diagram of the 2mode system's major components and power flows under various scenarios? Such diagrams are easy to come by for HSD, but I have yet to see one for 2mode.
- Why is this system advertised as being more suitable than HSD for heavy loads and large vehicles? I've never heard a logical explanation for this, possibly because (other than the general "AT versus differential" distinction) I have yet to see a detailed explanation (or diagram) of exactly how 2mode differs from HSD.
- Do you think there could be additional efficiency gains if the system was upgraded from AT/slushbox technology to DSG/gearbox technology? As we all know, there is a 5-10% efficiency advantage to be had here, at least in conventional drivetrains.

Thanks.

Hi Wri Consult:

___I like to start a blog to give what I can and of course see the reactions :angel: but am waiting to upload a real Preview until I receive some answers about the mid-sized diesels for the light trucks out of Europe, the total pack cap and the DoD vs. SoC from the PanasonicEV sourced NiMH pack.

___There are 2 MGSets, 3 planetary gear sets and 4 electric clutches in the 2-Mode tranny and by locking up MG1, they can transfer the input to the output with gear reduction with no losses other then gear mesh. They really do have a completely variable solution with one heck of an algorithm to control the torque and RPM multiplier of the input to the output shaft. There is no straight shaft through the tranny if that is what you were thinking?

___I am not sure about your second question although I have some notes about a similar question. I will look through the docs I have for an answer maybe later this week or next after all the LA Auto Show stuff I have coming up on Wednesday and Thursday …

___Yes, I have some of the power flow diagrams that have not been released but I need some answers to other questions before I throw them out.

___Probably as simple as comparing the actual towing cap. If you look at the HiHy’s and RXh’s towing cap vs. the non-hybrids, they do not have the same capabilities and the .2L loss even after atkinsonization does not explain the difference. The 2-Mode’s can do everything the standard 5.3 and 6.0L can do and more.

___Efficiency gains over and above the 2-Mode, probably not. Because the 2-Mode has the ability to lock up the input to the output through gear reduction of meshed gear sets and no TC getting in the way (there is no TC actually!), this thing has a lot of potential. The cost of the Pack is the only real problem I see right now but they do have the FWD versions on the road as far back as 1.5 years ago that I remember.

___Overall, the hybridization is what makes this monster receive the FE it does around town. Nothing I have ever heard of that weighs almost 6K pounds can touch 20 around town and this thing seemed to hit it with ease even in some of the worst traffic and conditions I have experienced. It appears as if GM is making this thing go into a serial like hybrid mode when confronted with this kind of traffic condition but I am not sure if it was the right choice given the inability to control ICE-Off vs. their algorithms controlling it for you.

___Out on the highway, it’s the atkinsonized intakes, ability to drop down to V4 mode, and limited pumping losses with solenoids bleeding off oil pressure which takes out the pushrods for intake/exhaust valve closure (GM is still using the push rod engine) and its superior aerodynamics that makes the real difference. I was not over 60 mph so I do not know how it acts beyond that speed but the 6.0L running on just 3.0L with an atkinsonized intake and 4 cylinders bottled up really does show some neat tricks that I thought only an MDX or HiHy was capable of. For a 5,800 pound monster, I was thoroughly impressed w/ 2-Mode although 21/22 per the EPA with gasoline at $3 - $5 is going to make a monster SUV tough to justify.

___I want to add that this thing has a > 11.0:1 compression ratio w/ flat head pistons yet still runs on regular unleaded. This is not an Atkinson trick like the HSD figures take into account but something else I have never heard of.

___Good Luck

___Wayne

Thanks Wayne. I still don't completely understand the thing but that helped. Didn't realize it has no TC!