Hi all,

I have an XC Falcon with a 4.9, 3 speed auto C4. I wrecked an XC Fairlane and removed a 9" diff. and tailshaft (along with alot of other good stuff). I took it all along to my local mechanics who installed it for me and adjusted the handbrake "because of the difference in wheelbase". Everything was fine until - the uni (at the diff end) crapped itself at 90 kph. The noise was one thing, finding a new uni was another as was getting 2 u bolts. Now after it's all back together my NEW mecanic tells me the tailshaft is too long - or the yolk is too long and that is why I have tranny fluid all over the place. Yes he replaced seals - he tried to rig a spring to hold the seals in place, but still no joy. Is this tailshaft too long - have I stuffed the box or is this guy a loser.

Cheers,
MJ

fairlane body is longer than falcon body.
so tailshaft is different length!
check the size of the dogleg [behind the rear door to wheel arch]
fit a falcon tail shaft and as long as you haven't damaged
the auto's extension housing all should be ok.

Hi you quoted that ; (((I have an XC Falcon with a 4.9, 3 speed auto C4. I wrecked an XC Fairlane and removed a 9" diff. and tailshaft (along with alot of other good stuff). I took it all along to my local mechanics who installed it for me and adjusted the handbrake "because of the difference in wheelbase". Everything was fine until - the uni (at the diff end) crapped itself at 90 kph.)))

OK how did the mechanic fit the fairlane tailshaft into you standard falcon???Then you drove it.There is a significant length difference between fairlane/ltd and falcon tailshaft lengths.

Thats the question - does this NEW mechanic know what he's on about or not. He tells me the yolk is going too far into the trans. because he thinks they put the Fairlane tailshaft in. I didn't think it possible to fit the Fairlane tailshaft in and your replies confirm that for me - thank you.

Is there a spring inside the yoke? That would normally prevent it from going too far into the extension housing.
It might be possible to fit a Fairlane driveshaft into a falcon with this spring removed.

By the way is your falcon a sedan? I believe wagons would have fairlane driveshafts also.

There is no such thing as a spring inside the slip flange, if there is it shouldnt be there. There should be wear marks on the outer of the slip flange where the extension housing seal was prior to fitting it into your sedan. Does the current seal match up to or close to the old wear marks? With the car sitting level(wheels on ground) there should be a gap of around 20mm from the seal to where the slip flange bottoms out into the transmission. This gap allows for any suspension travel. If there isnt enough you will have a very hard ride over bumps and you will damage the seal and bush inside the transmission. Im surprised the mechanic even attempted to fit a LWB shaft into a SWB car.