Hi everyone -

Thought I would introduce myself and see if folks here can help me with a few questions.

I just purchased at 2010 Chevy Silverado Hybrid. So far I've managed to put 191 miles onto the beast. It's my first truck ever, and my first Chevy since a couple of '67's I had back in the good old days.

I was able to get a pretty good deal on the truck - I bought it during October's Truck Month and got a good discount on it. I've been pretty happy with all of the "standard" options on the truck. The basic vehicle is pretty nice. So far, I'm really happy with things.

The truck I got was delivered to the dealer in March of 2010, and I purchased in October, so it sat on the lot for quite a while.

I'm hoping people here can help with some questions.

Is there anyway to determine the state of charge of the hybrid battery? From what I can tell, none of the (very few) readouts gives information about the state of charge. The one screen which tells you the instantaneous MPG doesn't seem to have any indication of when you are running on pure electric. Since the truck sat for so long, I'm curious to understand how one understands whether or not the battery pack is at full health.

I assume that all of the two-mode GM hybrids act pretty much the same. When you pull away from a stop, can you tell by looking at the instantaneous display if you are running just on battery? So far on my truck anytime I pull away from a stop, it looks (and feels) like I'm running on 8 cylinders. This is true even when I accelerate *very* gently. I was under the impression that you should be able to accelerate up to about 30 MPH under pure electric power, but so far for me that hasn't been the case. If I go from 0 to 20 MPH in 30 seconds, it does seem to be all electric, but any realistic acceleration seems to kick in the full power of the 6.0L V8.

Since the truck was sitting for so long, I have some concerns about the health of the battery pack, so am looking for some ways that people here figure out what their state of charge is, or what ways they have come up with to determine when you are running on just battery.

Has anyone hooked up a scangauge to the truck? Have you been able to figure out how to get a readout of SOC?

I've looked for forums for the hybrids for a couple of months and as far as I can tell, this is the most active. If there are other places to look - please let me know.

I also have gotten the feeling that dealers really don't know very much about the hybrids. Have you found any places where you can interact directly with engineers from GM to get and give information about the hybrids? I've been really surprised that I haven't found any place that GM or their dealers aren't actively participating on. I'm a big believer in hybrid technology and think it would be great to have a dialog with GM about how to improve things, but haven't come across anything that indicates that GM is listening anyway. I hope that is just because I haven't found the right place yet.

So - I hope to be able to contribute to things here, and to get a whole lot of input on the operating parameters of this truck. If you have any suggestions about understanding the SOC or other issues unique to the hybrids - I'm all ears.

Thanks.

 

Hi there, Just curious, Have you found or did the dealer salesman show you the two mode hybrid display on the stereo head unit?

It will show you the engine & batterie power path going to the wheels, ect.

To activate it, you will need to touch the menu button on the side of the stereo screen first, then touch the Hybrid button on the touch screen head unit.

 

I have the 1HY model, which doesn't have a NAV unit in it - so no touch screen

 

welcome to the club!

"Is there anyway to determine the state of charge of the hybrid battery? From what I can tell, none of the (very few) readouts gives information about the state of charge. The one screen which tells you the instantaneous MPG doesn't seem to have any indication of when you are running on pure electric. Since the truck sat for so long, I'm curious to understand how one understands whether or not the battery pack is at full health."

answer: NO not with any built in on board gauges

"I assume that all of the two-mode GM hybrids act pretty much the same. When you pull away from a stop, can you tell by looking at the instantaneous display if you are running just on battery? "

answer: if you accelerate with normal traffic 99% of the time you will be running gas/electric. if you choose the hybrid display in the nav screen you can see exactly what you are running on ICE or ELEC or both. By the way you need to re-learn how to drive with this system as very slight pressures on the throttle can bump you from elec to dual mode and also from v4 to v8 mode on the highway.

my yukon was built in jan 08 i bought it in feb 09. it had 400 miles on it from demos but was sitting a lot. so far it has been flawless except for one flaw in a wiring harness in the transmission that was a subcontractors fault

"I also have gotten the feeling that dealers really don't know very much about the hybrids. Have you found any places where you can interact directly with engineers from GM to get and give information about the hybrids? I've been really surprised that I haven't found any place that GM or their dealers aren't actively participating on. I'm a big believer in hybrid technology and think it would be great to have a dialog with GM about how to improve things, but haven't come across anything that indicates that GM is listening anyway. I hope that is just because I haven't found the right place yet."

my BIGGEST GRIPE with GM! there should be a mandatory hybrid sales EXPERT at any GM store that sells them. In my case I did months of homework to determine what to buy. my conclusion was based on that homework. I actually knew more than the dealer did! I wish GM would establish an insiders forum for 2 mode hybrids only where we could have an online dialog with GM engineers and such. Mercedes has a special forum for AMG owners which I joined after I bought my first AMG. It was very informative and helpful when I bought my second. I mention the 2 mode specifically because there is much confusion between the first generation hybrid failure that GM put in the early trucks. It was not in the same league as our cars and a LOT of people don't realize the HUGE differences. GM needs to do an add that says "hey we built a hybrid that didn't work so well so we went back to the drawing board built the new 2 mode....and we got it 100% right this time!"

good luck with your truck I love mine and I have been averaging 19.5 mpg the last 2 months in stop and go in town traffic only.

 

Thanks Jet.

I hope to be able to contribute some to the forum.

As you mention, this is a very advanced piece of engineering, but there is just about zero information out there in the wild about it. Dealers don't seems to know much about it - like you when I went to the dealer, it was pretty clear that I knew a lot more about both the mechanics of the truck, the package options, the accessories, etc. then the dealer did. I asked them specifically to run a hybrid system diagnostic on the truck before I picked it up, but don't think they ever did that.

Guess it's time to go back to the dealer and stand over them while they run the diagnostics.

It sure would be nice to have more information about the hybrid system. It would be great if a GM engineer would work with ScanGauge to ensure that the ScanGauge can pick up codes for SOC and state of health of the battery pack, along with other normal hybrid info. (of course it would be even nicer if the DIC showed this).

I think it's a mistake to believe that someone who buys a hybrid is just going to jump in and drive without ever trying to maximize MPG. The technology is there and if the proper information were there too, it would be possible to easily bump your MPG's up by 10% or more by paying attention if you so desired.

 

Lake,
Welcome aboard!
To know if you are in "pure electric", the engine will be off. So, the tach will show "auto stop" and the truck will just make that futuristic whine as it pulls away. On a flat surface or slight downhill, this is not too hard to do up to 30mph. The instant display will show 99mpg and V4 or V8 mode (depending on the state of the valve that controls the oil flow to the Displacement on Demand circuits when the engine shut off). Also, if you have an oil pressure gauge, it will show zero PSI during electric mode.
Now, when you go past ~12 miles per hour, the transmission has an "event" that requires you to lift slightly before this point to make sure it doesn't kick the engine on. In other words, if you are accelerating at the limit of the electric motor power, when the trans shifts (or whatever happens), this extra load causes the engine to switch on, but this is just momentary, and you can put you foot back in it again just after 12mph and continue to 30mph. This makes a big difference in running around town in all-electric.
Above 30mph, even coasting, the engine will start. This does not mean you are using it to power the wheels. The engine will just be charging the 300V battery. If you see 99mpg this means you are in electric mode, using the battery to power the vehicle, or even regen charging the battery with the vehicle's momentum.
The main tricks to get good MPGs without having to "hypermile" is to practice lifting every once in a while at steadystate to get the engine to switch to V4 mode, and to try and use the regen to slow the vehicle instead of the brakes. The latter is just a better way to drive. Look further down the road and plan your stops better. I just put tires on at 45K miles and my front brakes are like new. I'll probably get 100k out of them. This is worth a LOT of money compared to the Chevy Express Van this replaced. I was putting brakes on that pig every 15k miles and getting 12MPG.
Use the econ gauge and the instant MPG gauge. Together, these will tell you everything you need to know. I have the nav system and I NEVER use the Hybrid display.

 

I forgot that one as I don't usually worry about them in auto trans cars although I do pay attention to it at highway speeds.

dealers HAVE to have a mandatory factory trained tech in order to work on them so HOPEFULLY this is the case in your dealer. My dealer has 4 dealerships and all 4 techs are very knowledgeable.

 

It looks like several hybrid parameters are available on the bus - SOC and input current at the least. I'm not sure they can tell anything about individual battery cells or not. Most of determining the health of the system appears to be dependent on looking for error codes thrown by the system. It would be really cool to have a list of all possible hybrid specific error codes - then at least we have an idea of what the system monitors.

 

Hi, name is Tom Ling, site is nice. I am in the market for a 09/10 used Hybird Tahoe. Seen I have been reading a lot on the 08 that they have problems. Seen what I am reading is the 09/10 is better. Tx Tom

 

Hi Tom -

One place to get started is to look on a site like Autotrader.com if you haven't already gone there. They appear to have about 140 2009-2010 Tahoe hybrids listed - most from dealers but a few private sales too.

On the main search page - under:

Need more search options? + Search by mileage, color, engine, features & keyword

the "engine" box has an option for hybrid. This seems to bring up lots of hybrid Tahoes.

Good luck!