In the Car & Driver article referenced in the post by TKCamry they claimed that the EPA estimates are 43/37. I've seen this in other publications too. However, the actual sticker claims 40/38. Anyone know why the discrpency? Did Toyota lower the EPA estimates?

The manufacturer puts out early estimates that is then used by publications that actually lock in the contents of their articles well before the publication date. Later when the EPA tested, the actual numbers come out. But by then many car magazines have gone to press. As new Camry Hybrid reviews start coming out, they will have the new numbers.

Link to My Hybrid Car News Web Page

TK, aren't the EPA numbers provided by the manufacturers using EPA guidelines. I didn't think the EPA actually did the testing. That's why I don't understand why it would change.

Actually, it is both. The mfgs follow EPA guidelines and submit results to the EPA. But the EPA also tests cars to verify that the mfgs are following guidelines and are getting the same results as the EPA testing. The EPA may not test every single model variant in a line of cars, but they do test each model as far as I know.

http://www.epa.gov/fueleconomy/data.htm

Link to My Hybrid Car News Web Page

I think I read somewhere that Toyota had tweaked the HSD just before launching the product. I think they lowered the HP of the engine a bit. They may have done more. You may be able to google for this, but I'm not sure how easy it will be to find again. You could always e-mail Toyota and ask them.

The official maximum output of the battery was reduced from 45 HP to 40, which lowered the car's total power (ICE + battery) by 5 HP, from 192 to 187. The ICE is 147 HP.

You wouldn't expect a decrease in HP to result in the city mileage going from 43 to 40.

This could be a situation where Toyota submitted results to the EPA at 43/37 and THEN the EPA did their own testing and got 40/38.

That's my guess.

See more at the EPA "how we test" site:

http://www.fueleconomy.gov/feg/how_tested.shtml