Quiet down my X5 (reduce road and wind noise)?

[RhythmMachine]

My previous vehicle was a 2009 Mercedes ML320 diesel, and while the X5 is better in almost every way, it's WAY noisier than my ML320 was.

Part of it may be the run-flats, and I plan to replace them with a set of Kumho SOLUS 4S HA32 SUV tires (same ones I had on the ML when it was written off... quiet, smooth, and functional in snow), so that should help.

I never needed to close the (smaller) moonroof in the ML, but the beautiful panoramic one in the X5 is a huge part of the noise factor, especially at highway speeds, so I've grudgingly learned to close it up accordingly.

Any other suggestions?

[80stech]

Tires are probably the biggest problem but you might check if the windshield has been replaced with a thinner than original. Then door weatherstripping.

[RhythmMachine]

Originally Posted by 80stech

Tires are probably the biggest problem but you might check if the windshield has been replaced with a thinner than original. Then door weatherstripping.

Oh, I hadn't thought about augmenting the weather stripping around the doors. There are no gaps/tears or obvious issues, but I wonder if getting something additional (and thin) would help...

[ard]

Originally Posted by 80stech

Tires are probably the biggest problem but you might check if the windshield has been replaced with a thinner than original. Then door weatherstripping.

Also with many BMWs the *depth* of the glass in the body cavity can impact road noise. The TIS explicitly states this...BMW has specific dams to set the glass, and tools to get the depth right.


Safelite is one of the worst offenders, IMO...no bmw kits, no tools- just squirt in glue, plop it in....

[80stech]

If the door is out of alignment at all it can add a lot to wind noise.

[getty150]

I drove for years without the floating sun shade...this spring I installed them and what a wind noise difference it makes...Ive found that I would rather have quiet than the skylight.

[Daytonawim]

I replaced the runflats for normal tyres, that helps al lot, but 275 and 315 wide tyres make more noise than smaller tyres.

I have no problems with noise from the sun roof. But I hear some road and wind noise coming from the B pilar area.

Also I hear noise coming from the back of the car, my guess is that it comes from the bad insulated back door.


Sinds I had leaking inner doorpannels, I put some sound deathing ( butyleen) inside the door against the door skin. The door sounds now far less metallic and more solid. When tapping on the outside of the door.

[RhythmMachine]

I've started by adjusting the drop-down tailgate and main rear door, and that's helped to take out some rattle. I need to crawl into the back to listen while someone else drives to assess the wind/road noise, but less rattling is good, at least.

To adjust the lower tailgate, remove the plastic snap-in covers on either side of the tailgate where the prongs are attached that insert into the tailgate latches. Loosen the two bolts on each side (maybe 12mm?), then latch the tailgate and push forward firmly on each side, tightening up the bolts as you're pushing, to get them into the right place.

To adjust the main rear hatch, either go in through the access hatches on each side at the back or (what I did), pry out the little rubber stoppers on the larger rubber bumpers that the rear door rests against (about a quarter of the way up) and use a T30 bit to extend or retract the bumpers to get a solid, even fit.

I realize this description may not help much, but I didn't document it enough to do a DIY, and there are plenty of videos on YouTube about it, but wanted to at least give an explanation of the steps taken so far.



Next, I think, is to spend some time in the back seats and cargo area listening and feeling around while someone else drives to see where there's problematic noise or vibration.