Car is starting to make some odd noises around 20-30 odd. Its not the same as in my videos below, however, when jacked up, the noise in the videos has not been heard before (ie when setting up my Gear Idicator)

Its really clattery and metal knocking,and the sound seems to come from the diff - however, i know the engine could be the source - I really hope not. I have two videos below.

1) jacked up with the engine running and rears turning

2) still jacked up shoing slack in the prop to diff connection (i dont know if this is right)

The car has been mega fab for a year and 1000 miles doing a few track days under ite belt too.

I am taking her tot he Ring on the 16th Sept and want to be sire she is fine for the trip.

The car still pulls really well, and if I wore ear plugs, I would think nothing was wrong with it!

any advice etc would be great.

1) Video Running

http://www.youtube.com/watch?v=FkQwxV6YCOY


2) Video showing possible slack

http://www.youtube.com/watch?v=c2NFWMh5xkM



[Edited on 16/8/09 by Kriss]

[Edited on 16/8/09 by Kriss]

sounds like the diff, disconnect the prop and turn the flange by hand to see if you still have a large amount of play. There does seem to be a lot of back lash there.
Normally this would give a thud upon taking up drive , it sounds like a disk rotating are the wheels bolted on ???

When the props disconnected run the engine and go through the gears to rule the engine out

the wheels were bolted on yeah.

so disconect the prop and then try turn the input flange?

looks really tight at the engine end to get tot he prop, should be do able though i guess

Sounds like different noises at either end of the prop to me - you could have two wear issues.

Diff centre bearing?

Is the centre bearing in the diff or the outside?

I'm struggling to work out what I can do to locate the problem and then go about addressing it. Right now I don't know what is at fault

Cheers

Centre bearing is half way down the propshaft IE between the gearbox and the diff....

Try using a long screwdriver as a stethoscope to locate the source of the noise.

Looking at the amount of slack when you turned the prop, I would say that the whole problem lays in the diff, far, far too much play, there should be almost zero play. Diff out and adjust the backlash may cure it, but then again may not, if the crown wheel and pinion are stuffed. HTH Ray

i think you should ignore the centre bearing comments. looks like you have a single piece prop

Kris, I had my car up running on stands for the fist time in two years since I bought it, and my car makes the same clanking hoise - so I have no idea if it is normal or not. On the road, the car drives the same as it always has, and I cannot hear the clunking.

I rationalised as follows, was that the with the wheels of the ground, their is no rolling resistance, and so when power is transferred down the prop, the wheels actually accelerate to faster than the prop, then decelerate and then accelerate and so on, (I hope this make sense).

If I have the complete wring end of the stick , I too would like to know, so that I can sort the diff out if required.
cheers
Craig

Any guideabout adjusting the backlash or sticking in new parts or is it a pro job? I know my mate sent his diff away to change ratios on his mebabusa.

I too suspect fault is with the diff. Only a month till ring and being an uber impatient sod I am really wanting it diagnosed and sorted lol

any tests I can do to locate the issue? Finally, since day one, when you pop it into 1st from neutral it has banged big time!

quote:

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Originally posted by blakep82
i think you should ignore the centre bearing comments. looks like you have a single piece prop

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Well for my money the play doesn't look too bad BUT It really does look to me in the video where you turn the prop by hand that there LOOKS to be a big movement in the UJ. It may be an illusion but it doesn't look right to me.
Anyone eles care to comment on this??

Without any load - i.e. the wheels and tyres are on the ground you will get all sorts of "backlash" and "take up" play.

When on the ground and being driven there is resistance and the noise will be reduced - but obviously it wont go.

This is where a Torque Resilient Tube Propshaft comes into it's own.

Steve

The easiest way to check if you have excess back lash would be to drain the oil from the diff, take of the back plate and actually look inside. When you turn the prop the crown wheel should move immediatly and not have any delay, the correct backlash from memory is only a couple of thou. Cheers Ray