Fsti smith drone

[vxr2010]

I don't know if any one has thoughts on this one , it's a fsti its on 140 k miles , on very light throttle between 50 mph to 70 mph ish , I get a resonating drone noise it's difficult to tell if it's transfer or rear diff I don't know if it is transfer or diff I'm assuming it is , as soon as I accelerate normally it goes away , it's only there on light throttle , it does not appear to be wheel bearings , it sounds like resonating rather than worn gears , I suppose it could be early stages of a bearing failing , the diff and box appear fine noise wise when it's been driven under acceleration , I've checked out diff hanger bushes they seem OK , the rear diff bushes seem OK , any thoughts please,

[vxr2010]

That should read slight drone I love auto correct

[MDMA .]

when was the last oil change on the box / diff ? and what tread depth on the tyres ? sometimes can get a droning noise on some makes of tyres when they are wearing down. strange it is only at 50-70 mph. bearing noise is normally gradual as the speed increase, not just over 50.

[vxr2010]

Rear diff and gearbox changed recently , diff oil changed due to noise but no difference , rear tyres are a bit worn , fronts have more life in them

[MDMA .]

Give the tyres a swap round. Need to keep the rr the same as much as possible. Have a search for bearing noise. Will try and find the link, worth a read.

[DanielSan]

I had this on my blob a while ago. Helped all the diff, box, bushes etc. Turned out the be a wheel bearing. Couldn't locate it until it was pretty much dead.

[vxr2010]

Maybe a wheel bearing but no sign of any failing yet , are bearings straight forward to do ? And I don't think they cost that much ?

[DanielSan]

If they come out OK then it's a simple job but there's a high chance of knackering the drive shaft flange on removal.

I had one done and 4 months down the line the second one failed, ended up getting a second hand shaft from Japanese Performance Parts and putting that on as removing it for the second time finished it off completely.

[lemmingjames]

Does the sound go away if you brake? If so strip and rebuild the rear brakes as that solved a random sound i had

[vxr2010]

Hi it would do but it's speed and load related , it's a weird one , it sounds like some thing resonating , the diff and box are not showing the normal wear noises so it's not easy to track it down , a friend who got in the back of the car , as you look out the boot it sounded like it was on the right side , outer diff bush is ok and I flattened the supporting bracket no change to the noise , i would like to cure it but I think it maybe a case of it getting worse or failing to find where it is

[peter8171]

I had a wheel bearing go in my Impreza and it caused a whine / drone at certain speeds and loads. Initially didn't think it was as there was no movement in it when I jacked the corner up and tried to move the wheel. When the bearing came out, the race was destroyed and it also needed a new stub axle.

[vxr2010]

I'm surprised the axles get damaged by a bad bearing I've never had that issue on other cars , what actually damages the axle just too much play in the driveshaft ?

[peter8171]

The bearing was completely knackered on mine and the surface in the axle the bearing runs on was damaged due to the bearing race disintegrating. It left a load of indents and raised marks on the axle, so was better to replace it than make an attempt at a repair. If you catch the bearing early enough, this isn't a problem.