Dodge Durango Forum II Archive

Interior sound level measurements with my Dynomax Ultraflo...

Dodgeboy - 2001 SLT PLUS 4.7 AWD
n4taj@yahoo.com

I drove around a little today with the ol' decibel meter and have some readings some of you may be interested in. These readings were taken with a Realistic 42-3019 (remember, I said ol'!), which only accurately measures down to 60db. Unfortunately, I don't have any stock readings to compare these to. Maybe someone else on the forum can measure some?

Anyway, here are the readings from inside the cabin (keep in mind, these readings include wind/road noise):

550 RPM Idle: 60dB (slight blips in the meter would suggest a 55-58dB level)

1800 RPM (loudest point in RPM range under load): 78dB (dips to below 70dB outside of the 1750 - 2000 RPM range).

Wide Open Throttle to 50mph (peak reading): 84dB - it only hit this reading for a split second. It was normally around 78-80dB.

Normal crusing at 50mph: 66dB

I got the impression that at a 70mph cruise, the wind/road noise increased the sound level more than the exhaust, so I didn't record those numbers.

These readings were taken with the meter in front of the driver, with the windows up, fan and radio off and on smooth pavement. I realize this is about as far from a controlled environment as you can get, but it's a realistic test.

The muffler is the 6" round variety of the Ultraflo, with stock piping. I have heard that the oval version of this muffler is quieter on the interior, but haven't experienced it first hand.

Dave
www.dodgeboy.net

Wed Oct 31