Rep Power: 0

I'm a new Civic owner - 06 LX sedan with automatic tranny. Bought the car new for the mileage and Honda reputation. Car has 8,000 miles. Only problem I have is a noisy vibration that occurs in high gear (5th gear) when the car is running at 1500 RPM or less. The noise gets worse under load and then disappears as soon as it downshifts into 4th gear and RPMs increase. Dealer couldn't replicate the noise in the one trip to the shop. Is this normal noise for the new Civic model?

 
Rep Power: 0

You are getting to the low rpm when the engine starts to "lug"....pretty normal.
Another item maybe the gas, try switching to a name brand gas station eg: Chevron and see what happens.
good luck!

Plastics
07 Civic EX Sedan AT

 
Rep Power: 0

Last night, when I was out driving, I tried to see what happens if the AT is in 5th gear at 1,500 rpm. That's equals speeds of 65 to 70 km per hour.
There was some very slight vibration, detectable if you are looking for it.
However, even the slightest pressure on the gas peddle will make it down shift to 4th.
-try different gas, and see what happens...

Plastics
07 Civic EX Sedan AT

 
Rep Power: 0

Have the dealer look up Service Bulletin 06-059. It fixed my problem.

 
Rep Power: 0

Yes I think the computer is shifting too early from 4th to 5th.

 
Rep Power: 812

those auto trans are very weird. i test drove one and i got upto 35 mph and the car already put itself in 5th gear. it shifts way too fast and i constantly had to press the gas down to make it downshift.