Just got a issue with my daily driver BA falcon.
Lately I have been getting this drone coming from the underneath of the car - I think its towards the rear.
It almost sounds like a tyre drone noise but its not for the reasons below.
It does not do it when I start the car or rev it in neutral. As I was thinking it was a muffler / exhaust problem at first, but I have even had it up on the hoist at a muffler place and seems all good to the guy there and it would usually do it revving in neutral.
Anyways it really only makes the noise when the car is under load / acceleration. Don't really hear it too bad at highway speed as usually not accelerating hard once at speed. But around town it is real loud, I can hear it best when coasting at around 40 klms/hr and then accelerating a little.
It is most noticeable to me around the 1000 rpm - 2000 rpm range. I don't have to accelerate hard just touch the accelerator is starts droning then if I lift off it goes away and so on.
I was thinking it must be drive-line. I was thinking diff, but I thought that that usually only makes noise going round corners if it bad and my car makes no noise around the corner unless i have the accelerator down like mentioned previously. My next step was to change the diff oil and see if that helps... don't think its been changed in a long time..
Anyone heard of anything like this before.. could it be diff / gearbox / drive-shaft??? I am a little confused. The car still seems to drive fine, but I just want to sort it out before the car brakes down on me somewhere.
Also while I am on the subject of noisy falcon. The only other thing wrong with the car is the usual BA Falcon "clunk" from the back of the car. I had a look under there and it seems as though the Main Diff bush is shagged like usual. Has anyone tried to change these before. I read that you need a hoist and takes 3hrs.... as I have no hoist i was thinking of stumping up the cash for a pro to sort out. Would be $500+ I would imagine... could i just leave it like everyone else, will it cause any major problems?
Any thoughts would be great.