Motorway thumping noise

[JPL]

Hi all - had a very odd booming/air thumping sound at 70mph today - was like the van was being hit by a marvel style bass cannon - was unbearable

definitely not engine - anyone experienced this (have a manual t30 swb)

hasn’t happened again and went if I dropped off had sped up- might have been one of those odd situations with the wind

thanks

 

[Grim Reaper]

Cowling under engine come loose? or one of the plastic guards underneath?
You often see these things flapping in the wind and wonder how the driver can't notice it.

 

[JPL]

Will take a look mate - good idea -putting side bars on anyway so will be a good opportunity - it was an incredible noise

 

[paulfr]

Have a look at the wheel nuts,may need tightening.My rear nearly came off!

 

[JPL]

Christ don’t say that - will check in the morning first thing

 

[paulfr]

If it's not the engine..then i'd put money on it being one of the wheel's.Check the nut's are tight........i bought a torque wrench because we had a lucky escape!

 

[DXX]

Should run as quiet as Rolls Royce, VW put 4 pieces of sound deadening in the back, 30cm x 30cm!

 

[Pete C]

Any one of the plastic guards under the vehicle could be loose and flapping.
Check both sides of the vehicle front to back, and also check the engine under tray if fitted.

Pete

 

[JPL]

Had a good look today and checked wheel nuts but all seems ok - tbh the sound was like a harsh version you sometime might have felt when yuh go from flat motorway to ground that’s got sections in it although brutally louder

sure it will come up - I wondered if anyone was going to say it’s common tying to throw a shoe box. Down the motorway with average to poor aerodynamics

thanks all

 

[Village]

Are you sure it wasn't actually the road surface? The booming resonation on some sections of the M25, between J7-J9, is genuinely alarming and initially made me think there must be something very wrong with my van, but it's definitely the combo of road surface/tyres/20" wheels

 

[dErZ]

Are you sure it wasn't actually the road surface? The booming resonation on some sections of the M25, between J7-J9, is genuinely alarming and initially made me think there must be something very wrong with my van, but it's definitely the combo of road surface/tyres/20" wheels

I have a T32 Shuttle still running standard suspension and 17" and that section is terrible! Im hoping getting new suspension will sort it.

 

[Littleblackflash]

Me too, I'm 50mm lower on 20" and that section of the M25 J7-9 is alarming. When it starts you think the tyre has popped or something's fallen off, especially when towing my race car. I have to slow down to 55mph to make the resonance go away. I was thinking some B14's would help me (excuse)

 

[Broadside]

Those sections of concrete motorway with expansion gaps are horrible, I did actually pull over on to the hard shoulder last year because I thought I must have a flat tyre.

Regarding the booming noise I have in the past had a seized brake caliper that was only binding on fully when the brakes heated above about 50mph, the resulting noise was a very loud but quite low frequency so that it sounded like a constant boom. Worth checking that your brakes aren’t binding on.

 

[SamD]

check your tyres, ours had a slight egg on the rear passenger side and it made a weird noise at speed

 

[JPL]

Me too, I'm 50mm lower on 20" and that section of the M25 J7-9 is alarming. When it starts you think the tyre has popped or something's fallen off, especially when towing my race car. I have to slow down to 55mph to make the resonance go away. I was thinking some B14's would help me (excuse)

Could definitely be this - 50mm lower and on 20s too

this is what I was hoping to hear tbh