xc90 suspension noise

[fifthwheel]

Hi all, I have a noise from the rear of my 2006 xc90 186000 miles when driving.
It sounds like I have run over a lump of wood or the exhaust banging on the body.
What baffles me is it happens on a good flat road for no apparent reason and I cant seem to make it happen again even driving on a bad surface/potholes.
It is very intermittent it happens maybe two or three times in four miles.
Any ideas? Thanks John.

[docjd]

Had similar problem from front of car -had both front wishbones replaced -all gone and handles more assuredly!-only 89000 miles
May be suspension related at rear as well??

[undercoverxc90]

Have you checked the hangers on the exhaust? They are a bad design and rust off - if the exhaust is not suspended right it can do this - we had it once and it was very intermittent - a knocking noise - only when the exhaust got into a certain 'momentum' that it did this - although it happened every time we went over a certain humpback bridge and the 'bounce' caused it to rock in a certain way. Thought it might be worth mentioning

[john langrick]

And John, have you tried the 'fifth weel' , i.e, that the cable that supports the spare wheel is tight and the spare not rattling around under the floor of the boot?

John l