Morning all, bit of help please;

 

Since fixing a front end rattle with a nearside drop-link I've developed a road speed, not engine speed hum which APPEARS to be from the offside front area. 

 

I have fitted a new offside drop-link, and 2 x new front tyres with no perceptible change. 

 

Discs are brakes are incredibly rusty, and when wheels are in the air there's movement on the driveshafts but that appears to be in equal amounts both sides. 

 

No sound on full lock going in circles both ways. 

 

I'm thinking wheel bearing, but why did it come on after the change of drop-link, and on the opposite side? Or is that just a co-incidence?

A few pointers.

Is it noticeable when car jacked up and spin the wheel by hand? Seems you've ruled out the driveshaft CV's, so next on the list to check your work (not meant to be an insult) for anything rubbing rotating items, Same type tyres?  Does the sound change when braking trapped rust debris or sticking calliper? Bearings maybe, does the sound change when cornering.   

Very difficult to spin up front wheels with disc brakes, driveshafts & in the case of the RH wheel turning the propshaft as well.

 

My way of deducing if a wheel bearing is making the noise is on a wide road without other steer to the other side so the weight transfer puts more load on the bearing, if it gets noisier then its failing, alternatively steer the other way to see if it becomes quieter.

If you can lift the wheels off the ground and spin the wheels one at a time then try this:-

With the wheel spinning put your hand on the coil spring nearest the wheel and you will feel, in the spring, if the bearing is no good.

 

Thanks, AG Falco

Thank you all, I have to say I've had bearings go in the past and this feels different.

 

I need to do some figure 8's in a big car park, and get the wheels up in the air - it never occured to me that the spring would transmit any bearing gremlins. 

It doesn't it sort of acts like a tuning fork and your fingertips are very sensitive, MOT testers do it but crucially they have the car at chest height on the ramp and can use both hands and all their force to spin the wheel up, they can also easily access the spring although most touch the strut housing, none of this is practical with the car on axle stands and you kneeling, with the drag of the brake disc and the rear prop on a 4x4 the wheel will have stopped before you can change position to touch the strut.

 

MOT testers often get their assistant to continuously spin the wheel while they feel for vibrations where there is drag present.

 

Oh for the good old days of brake drums.