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2006 Chevrolet Impala

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Comments

  • raym0016raym0016 Posts: 7
    I get about 22mpg in a lot of mixed driving but mostly city in my 3.9 LTZ. I can get MUCH better than that on the freeway. This is just fine for me because my point of reference was a 2003 trailblazer that I couldn't get better than 15mpg in!
  • quietproquietpro Posts: 702
    Charts2,
    You sure do have heartburn for DOD. All I can say is don't buy it if you don't like it. I'm very happy with my car and the DOD. Some points I'll make in this discussion:

    1st) I have not seen any itemized charge for DOD. As I stated in an earlier post, I'm fairly certain it's just a programming change for the engine computer, no physical hardware. At most, the added cost would be for fine tuning the engine programming which I imagine gets a lot of attention, DOD or not.

    2nd) DOD engages more often then you're thinking. I drive my car daily and whenever I reach a cruising speed, be it 20 mph all the way to 70 mph, as I ease up the throttle, DOD engages. In good traffic, I accelerate for 10-15 seconds and then cruise for the next 5-10 minutes. So, DOD is engaged for the majority of my commute (assuming traffic is actually moving).

    3rd) There is a cost benefit whenever any technology reduces fuel consumption (not necessarily cost-effective). I disagree with your assumption that DOD actually adds cost to the vehicle; at least to dollar amount you contend. If fuel use is reduced, overal consumption drops, demand drops, (hopefully) prices then drop.
  • jz68jz68 Posts: 61
    If anyone who works for a dealer could tell me if there is any information floating around about battery drain it would be greatly appreciated. :confuse:
  • charts2charts2 Posts: 618
    The 3.9 V6 that will go into the 2007 Impala will be rated at 233 hp. A drop of 9 hp from 2006.
  • quietproquietpro Posts: 702
    Worr,
    For strictly mileage, the 3.9L is probably the better choice even though the EPA only rates it at 27 mpg highway(compared to the 5.3L at 28 mpg highway). If economy is your #1 concern, obviously the 3.5L is the best choice.
    In my case, economy is very important but I have always loved the sound of a V-8 engine. I managed to get my first one when I bought a '94 Mercury Cougar (it also had rear-wheel drive, which I prefer). Unfortunately, I was involved in an accident and the car was totaled out by the insurance. In 2002, there was no V-8 or RWD vehicles out there (in my price range) but I found the 02 Monte Carlo SS which, although it only had V-6 and FWD, was great in all other aspects. The amount of technology Chevy packed into that car, along with it's great fuel mileage, made it an easy decision. Now, Chevy is putting extremely powerful V-8s in the same car. Fuel economy takes a small hit but the driving pleasure is much improved. So, I'm paying a small premium (average 1-2 mpg both in highway and city driving) to drive a car that makes me grin every time I pull away from a stop. I consider that a bargain. :)

    If you test drive the SS and love the sound of the engine, it may be the right choice for you. If that isn't important (as was the case with my sister), the 3.9L still offers excellent performance and a little better economy.

    I've mentioned before in this forum that we currently have three '06 Impalas in our family; my SS/5.3L, sister's 3LT/3.9L, and nephew's 1LT/3.5L. We're going on four months and all of us have no serious complaints.
  • steve333steve333 Posts: 200
    I almost find theres too much legroom in the Impala, I cant imagine that will be a problem.
    As for the Altima, Nissan's suck. Horrible reliability and their service is awful. My mothers friends Altima has 7 recalls and she said the service is so bad she is badmouthing Nissan to everyone she knows.
    If you're going to go Japanese go with Mazda. Good, sporty cars.
  • charts2charts2 Posts: 618
    Never said anything about not likeing the car. However everytime any technology is added their is a cost. Do the math on your own car and if your saving hundreds of $$ a year with DOD your ahead, but I just don't see it. My opinion is as valid as yours.
  • worrworr Posts: 45
    quiet pro wrote:

    "If you test drive the SS and love the sound of the engine, it may be the right choice for you. If that isn't important (as was the case with my sister), the 3.9L still offers excellent performance and a little better economy."

    Thanks, quietpro.

    Engine sound ranks low on priorities. They are, again, leg room, power and economy. The Impala SS meets the first two squarely. It sounds like you gain only a little MPG with the 3.9 and but gain more power with the 5.3 so the trade off isn't a fair comparison.

    Also, it was my hope the 5.3 would retain some value because it wouldn't be sold into fleets. There are plenty of LT3s in the rental market.
  • vanman1vanman1 Posts: 1,397
    Bummer on the HP drop for 2007 but hopefully the DOD will yield over 30 on the highway.
  • quietproquietpro Posts: 702
    Worr,
    Good point on resale. I like to think you're correct; that would bode well for me. Personally, I'd rather have a top of the line Chevy than a stripped version of some upper level brand.
    There have been some folks who mention the limited rear seat room but that only becomes a big issue with tall folks in the front seat. In my case, you don't want to sit behind me but my friends (average 5'10" height) have no issues, front or back.
  • rayainswrayainsw Posts: 2,476
    “As I stated in an earlier post, I'm fairly certain it's just a programming change for the engine computer, no physical hardware. At most, the added cost would be for fine tuning the engine programming which I imagine gets a lot of attention, DOD or not.” - quietpro

    From GM:
    “The key to DOD’s efficiency and virtually imperceptible operation is a set of special two-stage hydraulic valve lifters, which allows the lifters of deactivated cylinders to operate without actuating the valves. These lifters, used only on the cylinders which are deactivated, have inner and outer bodies which normally operate as a single unit. When the engine controller determines cylinder deactivation conditions are optimal, it activates solenoids in the engine lifter valley which direct high-pressure oil to the switching lifters. This oil pressure activates a release pin inside the lifter which allows the outer body of the lifter to move independently of the inner body. With the pin is released, the outer lifter body moves in conjunction with camshaft actuation, but the inner body does not move, thus holding the pushrod in place. This prevents the pushrod from actuating the valve, thereby halting the combustion process. “

    - Ray
    12,500+ miles on my 5.3L V8 (GP GXP) & no issues with DoD . .
  • charts2charts2 Posts: 618
    Additional information re: DOD Higher capacity oil Pump and larger coils on the coil near the ignition are needed for DOD. New Block casting has to be redesigned for oil galleries to meet oil requirements for DOD. Transmission has to have its own controller due to the demands of DOD puts on the ECM. DOD on the 3.9 V6 drops the left bank of cylinders when in DOD mode. So with the 3.9 more wear will be on the right side cylinder bank. The loss of 9 hp was because of the changes that DOD incorporates.
  • rayainswrayainsw Posts: 2,476
    My view of DoD:

    Given:
    The consumer & the federal government (CAFE) are demanding higher fuel mileage and customers also increasingly desire better acceleration \ performance. With additional convenience items (power seats, etc) that add weight to vehicles.

    These goals are largely in conflict.

    In order to facilitate development & sale of such W Body variants as the SS and GP GXP with good acceleration (low 14s in the Quarter Mile at 100-ish = ‘good’ in my book) and also, still meeting the CAFÉ requirements means developing technology that allows the highest possible EPA fuel mileage numbers. Or at least this is highly desirable.

    12% increase in steady state MPG (say 30 vs 26 or 27) at (EPA test speeds = still max. 60 mph!) cruise likely allows a higher posted EPA highway & average MPG number and (with GXPs now accounting for a rather high proportion of GP sales and likely SS also a significant portion of Impala sales) allows improved CAFÉ numbers.

    So – I was able to purchase (at a relative bargain price, IMHO) a good accelerating, V8 equipped sedan capable of at least ‘decent’ fuel mileage.
    - Ray
    Happy with my DoD equipped 5.3L V8 in most every way . .
  • that sucks. I thought they were gonna be randomly shut off, so that the wear and tear is proportional for each cyllinder. That really sucks, people are gonna windup having 1/2 the engine be older and in worse shape than the other half!

    Has anone heard the news about GM switching to 3 valve heads with its OHV engines? Its based on an old article in wikepedia. I can't find the article now, though.

    Still, its a good thing GM is advancing engine technology.
  • charts2charts2 Posts: 618
    The 5.3 V8 has random shut off only.
  • rayainswrayainsw Posts: 2,476
    In what way is this ‘random’?

    “Displacement on Demand (DoD) System Description
    To provide maximum fuel economy under light load driving conditions, the engine control module (ECM) will command the displacement on demand (DoD) system to deactivate engine cylinders 1 and 7 on the left bank, and cylinders 4 and 6 on the right bank, switching to a V4 mode. The engine will operate on 8 cylinders, or V8 mode, during engine starting, engine idling, and medium to heavy throttle applications.”

    - Ray
    Confused . .
  • quietproquietpro Posts: 702
    Good DOD info, folks. I looked for some technical info on how DOD works a while back but didn't devote much time to it. Based on what all of you have provided, I can see a disparity on wear between active and dormant cylinders but I don't believe it will become a problem. I will assume that wear on the pistons, rings, cylinder walls will remain consistent unless combustion adds to friction. The only real change is the lifters and pushrods that will not be active and a lighter load on the cam lobes involved. Since DOD is only active under light load, I'm betting the difference in wear is negligible. Of course, I'm not an expert but it wouldn't make sense for GM to deploy a new technology without being sure it wouldn't cause issues down the road. A batch of lemons would almost surely cripple them. Anyone remember the aluminum Vega engines? Is it any wonder it took over 20 yrs for GM to feel comfortable building engines out of aluminum again? :)
  • charts2charts2 Posts: 618
    Your right it isn't random. So on the 5.3 V8, over time cylinders # 2,3,5,8 will have more wear and tear, then 1,4,6,7 as how I read it.
  • charts2charts2 Posts: 618
    (Off topic) You said anyone remember the aluminum Vega engines?. I bought a brand new Vega GT in 1973. Went through 4 engine blocks in 3 years, and finally the car rusted out. GM cut corners by not putting sleeves in the cylinder walls but used some kind of silicone or lubricant that broke down after about 10,000 miles and you burned oil by the barrels. GM made a lot of mistakes in the 70s through the 90s by cutting corners
  • quietproquietpro Posts: 702
    Wow...you really DO remember the Vega. ;) But, to be fair, I think everything rusted out back then if you lived anywhere near snow. I don't remember seeing any make survive winter salting until the K car came along. Iacocca deserves a lot of credit for durability of today's cars. Too bad THEY stopped thinking after coming up with the K. :P
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