Compare 4cy,04 and 6cy,06
 

I find both Window stickers for both 04 and 06. The engine for 04 6i was made in Mexico. and 06 was made in USA. It seems like the 4 cy was not made in Japan. Both transmissions were also made in Japan. For the fist 6,000 miles in both cars. 06 hasno problem so far. 04 6ihadsome warranty repairing, such as suddently stop in freeway traffic. I prefer the engine is made in USA than Mexico.

Are all 4 cy made in Mexico, including speed6? Are all 6 cy made in USA?

The MPG for 04 6i(4cy) is 22-29. 06 6s is 20-27. 07 6i is 24-31. 07 6s is 20-27.

RE: Compare 4cy,04 and 6cy,06
 

Well I think it depends on where the car is manufactured. It seems that Mazda produces the 6/Atenza in China and Thailand for those markets as well as in Japan for Europe, Austrailia and some Asian markets. If I'm not mistaken, allNorth AmericanMazda 6 production is at the Auto Alliance Int'l.in Flat Rock, MI (right along with the Ford Mustang). I don't know for a fact if all ofZ (4-cyl) engines are built in Mexico, but it is not inconceivalbe that this may be the case as it may be more ecconomic to manufature them there rather than ship them all the way from Hiroshima. American production V6 engines are built at Ford's Cleveland engine plant.

RE: Compare 4cy,04 and 6cy,06
 

Here's something else to consider. The Ford Fusion is built in Mexico and it also uses the Mazda designed I4 engine. Considering that Ford has control of Mazda, sometimes the differences between Mazda and Ford engines are a little blurry as engineering from both companies is applied to many of thier vehicles. In this case, the engine is built in a Ford engine plant and utilizes a Mazda design.