Weird humming noise

[Nickyboy]

Anyone got any ideas on this

Near the end of a 500 mile trip over Christmas the car ('05 CV8) developed a kind of humming noise from the rear end. It starts around 30mph, loudest between 30-50mph. You can hear it at cruising speed but it's not massively obvious.

Asking around i've had people say it could be anything from uneven tyres to a dif on the way out. I've kind of discounted the dif and a prop centre bearing as from what i've read they won't sound anything like this noise.

Anyone got any ideas? I've not had the chance to get underneath it as yet so trying the obvious routes first.

[Nickyboy]

vxr2010 said:

check your tyre pressure could be low or not equal , could be the pads , how loud is it as these cars are not quiet , is it definitely mechanical , could be handbrake catching a bit , on humerus note if you have some one locked in the boot then let them out

Pressures were 2psi over recommended before the trip so i adjusted them before setting off, it was only the last 20 miles or so i noticed the noise. I've since put the pressure back to what it was originally.

I'm not sure whether it's mechanical, it's constant above say 30mph, seems to get quieter above 50 but is always there regardless of type of road (not that i really have any other surfaces round here i could do that speed on)

I did notice on recently the handbrake seemed to stick on albeit briefly when heading off in the morning and again after leaving work on one occasion. ( like after leaving it for a couple of weeks when on holiday)

[Nickyboy]

vxr2010 said:

in may be a case of put hand brake on very lightly and drive off , never do put handbrake on when you are moving , it may clear some of the muck off the shoes , if it’s pads try left foot breaking at speed and see if the noise changes , if it is a bearing it can be done in situ and is easy to do plus you don’t need any specialist tools just a standard bearing puller , how loud is the noise , i have a noise on the back of the foz it’s not there all the time , i tried changing a wheel bearing no luck there , it’s not intrusive every thing works fine so it’s been left , it’s got no worse it’s not effecting any thing so i dont bother about it now , monaro’s are a bit agricultural in places but are a great car

I tried this tonight, pulled it on slightly and pulled away, was ok for a few feet then suddenly stopped as if the shoes had suddenly gripped tightly. Let off and carried on fine again. The noise isn't loud as such, my g/f couldn't even hear it until i turned everything off and pointed it out when it was at it's loudest. At cruising speed it's not really noticeable, just as i said around 30-50mph

[Nickyboy]

Thanks all, once the stty weather is out the way i'll crack on and change the oil etc. Tyres will probably need replacing by the summer anyways

[Nickyboy]

Bit of an update, traced it to the rear wheel bearing, it got slightly louder in the past week and noticed when taking a corner and taking load off the o/s the noise almost went away. Ordered an OEM one from Rock Auto but won't be here for 10 days so having a cheaper one fitted Friday in time for Ace Cafe

[Nickyboy]

Dropped it off on Friday at my trusted garage, popped in later in the afternoon to see how they got on, car was still on the ramp with hub firmly in place It was seized solid! Even with the proper tools it wasn't going anywhere, left it with them and went back yesterday lunchtime and it was all done. Was a complete pig apparently, bearing is an extremely tight fit so had to be cut out, this was after applying much heat to get the hub off. Not sure what the bill is yet, popping in tomorrow once he's worked it out, luckily their labour charges are very reasonable.