[exon]

Got my X3 35i for a month and find the exhaust drones when cruising around 75-80, especially when in 8th gear and going up hill.

Anyone notice the same thing? What's the best aftermarket mod to reduce droning?

[n55x3]

When there is load on the engine it will drone a bit, not much you can do about that. Maybe shift back into 7th (increase RPMs slightly) and the drone will turn into more of a wail which might be less annoying. Stepping up to a larger model like X5 would probably eliminate much of that drone due to increased sound deadening materials used in the more upscale vehicle. You won't find any after market exhausts that are quiter, typically the after market exhaust goes the other way in that it will be louder.

My wife drives our 35i X3 daily and for the first 3 years of ownership I had unplugged the exhaust flap which created even more drone but I liked it as I liked hearing the N55 do it's thing (typically the flap only opens under cold starts and hard acceleration). Just last weekend I plugged it back in (now flap works as intended) and I was shocked by how quiet the X3 rides now.

[lbjgh]

There is a flapper in the muffler that opens and closes (search golf tee mod).

Perhaps the valve is not operating correctly...

I find the 35i fairly quiet at 'speed'.

Originally Posted by exon

Got my X3 35i for a month and find the exhaust drones when cruising around 75-80, especially when in 8th gear and going up hill.

Anyone notice the same thing? What's the best aftermarket mod to reduce droning?

[The X Men]

What some people called exhaust drone, other call exhaust note The 28i doesnt have the same exhaust note, its quiter. I am guessing the 35i's exhaust system is a bit more free flowing than the 28i's. To get rid of the exhaust note, you can try changing the muffler to a more restrictive one like the one you can find at Midas

[Pitiful Old Man]

Have your exhaust system checked. Our 2011 35i with 30K+ miles has no noticeable drone. Could be a gasket, the valve, or a problem with the muffler.

[DonC]

I like it!

[c3uo]

Mine has droned on highway since new. Hate it. Told it was normal. It is worse below freezing as exhaust steel and floor pan resonate more at low temperature. Otherwise love the vehicle. Have thought about trying remus exhaust and/or adding more sound insulation to trunk floor liner. Don't hear engine at all, only exhaust and wind noise on highway.

[danox3]

Originally Posted by Pitiful Old Man

Have your exhaust system checked. Our 2011 35i with 30K+ miles has no noticeable drone. Could be a gasket, the valve, or a problem with the muffler.

I would suggest this too, though it's probably normal.
Glad I found this board as I just got an M Sport 35i.

[exon]

X5 doesn't seem to have that flap. It has dual exhaust so probably don't need the flap to provide enough air flow.... That's my guess.

I will probably looking into putting some sound proofing in the trunk area.

Originally Posted by n55x3

When there is load on the engine it will drone a bit, not much you can do about that. Maybe shift back into 7th (increase RPMs slightly) and the drone will turn into more of a wail which might be less annoying. Stepping up to a larger model like X5 would probably eliminate much of that drone due to increased sound deadening materials used in the more upscale vehicle. You won't find any after market exhausts that are quiter, typically the after market exhaust goes the other way in that it will be louder.

My wife drives our 35i X3 daily and for the first 3 years of ownership I had unplugged the exhaust flap which created even more drone but I liked it as I liked hearing the N55 do it's thing (typically the flap only opens under cold starts and hard acceleration). Just last weekend I plugged it back in (now flap works as intended) and I was shocked by how quiet the X3 rides now.

[exon]

Dealer said it is normal...

The 28i is much quieter at cruising, surprisingly.... My previous 535i doesn't drone one bit.

Originally Posted by danox3

I would suggest this too, though it's probably normal.
Glad I found this board as I just got an M Sport 35i.