G'day there,

I went to my long time mechanics last week and after an inspection on my 2007 BF Faclon ES Mk 2 6 speed petrol 6 cylinder, after some long years a few bits needed replacing. Car had only done 110,000km

front engine mounts were leaking, tail shaft centre bearing & uni joint, the diff mount bush (big tennis ball) and the 2 side diff support bushes were replaced. Mechanic has done hundreds of these, marked it all out, weights, washers all returned etc Front donut near transmission end of tail shaft was fine

Got the car back and between 35/40 km i could feel and hear a driveline noise, took it back to the mechanics, at 100/105 km on the hoist you can still hear this noise even after putting it in neutral. He suggests after pulling apart and reassembling with the same noise, that we let what ever making the noise fail (he suggests its a wheel bearing that currently looks ok or something else that he can't pick, he is not sure)

I remember reading years ago of a similar problem somewhere falcon 2007 sedan xr6 6 speed and the bloke had to take it to his ford dealership, and they had to run the car at 100 k/h or so on a 4 poster with a scan tool for 2 hours to do something?? after identical work was carried out. Has anyone else heard of this issue or have a solution??

I had a similar incident with my wife's car after replaced complete driveshaft because of the center bearing,I test drove it and it seemed to be fine,not long after I had to go away for a week and it developed a slight hum at certain speed to which the wife took it to 2 different workshops and they couldn't work out the problem -so when I returned home I got it up on stands and checked it out and it all looked fine but proceeded to undo the rear part where it connects to the diff and found it had caught on one side on the last couple of threads causing a slight kink on the way it joins the diff-I loosened all bolts made sure it was fully seated and retorqued the bolts and it was fine.
But hers is a BA 4 speed and its only a suggestion as it could easily be something else.
Cheers Johnny.

Thank you Johnny, I'm going to get my tail shaft rebalanced Wednesday. the owner of a local driveline mechanic also told me that the uni joint should be a genuine and not aftermarket like a repco one. He said genuine ones are just a bit better balanced and are a tiny bit chunkier, hence the vibration. He sees about 5 falcons a week due to this problem

Interesting comments. My BA has always had a slight hum since ive had it. Since 2007. Kicks in as soon as i hit 80 stays till about 90 and seems to dissapear 100 up.
Everyone tells me its common on 4 speed BAs that ive asked.
All drive line is fine also.

GDay 93EB, chat to a tailshaft balancing mechanic and get a second opinion, loose the hum!!! when hey balance the tail shaft they add additional weights to the plastic ones near the diff. The mechanic was telling me they find the high and low spots on the tail shaft and weight it out perfectly!!! Makes sense, think of it as a wheel alignment except its your tail shaft