Weirdest running gear noise.

[Nicholas_taylor]

I lent my car to a friend and it came back with a weird scraping noise. I know a fair bit about cars but this is absolutly doing my head in. Trophey goes to who ever has an idea. No noise rolling in neutral, no noice when clutch is in and it goes away when i accelerate. Just rolling in gear and deceleration produces a grinding, scraping kind of noise that speeds up depending on how fast the car is going. Sounds like "schur schur schur" but it seems a little faster than the revolution of the wheel. The left hand side wheel is a tiny bit wobbly but i dont know if it could cause it. Doesnt change turning or breaking mainly there when im rolling in gear down a slight hill but its pretty loud. I changed gear oild and checked mounts. Its had a new clutch about 20k ago. I hope to God its not in the gearbox somewhere, hopefully its drive shaft or bearings but it doesnt really make sense. Anyone got an idea? Thanks

 

[STEVE.M]

I lent my car to a friend and it came back with a weird scraping noise. I know a fair bit about cars but this is absolutly doing my head in. Trophey goes to who ever has an idea. No noise rolling in neutral, no noice when clutch is in and it goes away when i accelerate. Just rolling in gear and deceleration produces a grinding, scraping kind of noise that speeds up depending on how fast the car is going. Sounds like "schur schur schur" but it seems a little faster than the revolution of the wheel. The left hand side wheel is a tiny bit wobbly but i dont know if it could cause it. Doesnt change turning or breaking mainly there when im rolling in gear down a slight hill but its pretty loud. I changed gear oild and checked mounts. Its had a new clutch about 20k ago. I hope to God its not in the gearbox somewhere, hopefully its drive shaft or bearings but it doesnt really make sense. Anyone got an idea? Thanks

Welcome & congratulations on joining the Forum.
Please don`t panic,my 172 has done this since I bought it at 90K miles.It`s discernable,,but not alarming in 1st & 2nd on the overun below 3,000 rpm.
Over 16k miles it has not got any worse,the wheel bearings have been replaced,so it`s not that,and the gear oil looked quite healthy when I changed it.I have also replaced the RH driveshaft and cannot find fault with the LH.
Long term,my plan is to aquire another gearbox,have it reconned and fit it when the clutch eventually needs replacement.
I can`t say I have been in other cars to make a comparrison,but suspect it may just be a characteristic.
Any observations from other owners would be welcome.

 

[Nicholas_taylor]

Thanks for the reply Steve, its good to know it might not be to serious. It is quite loud tho, if you could imagine the noise you get sticking your finger in a oscilating house fan with a touch of a grinding tone. So its pretty annoing. I think it is either clutch or diff related but would hate to have to change gearbox if its something simpler. I put the car on stilts and spun the wheels. Ill try put a video up as there seems to be a lot of play/slop in the diff.

 

[STEVE.M]

Thanks for the reply Steve, its good to know it might not be to serious. It is quite loud tho, if you could imagine the noise you get sticking your finger in a oscilating house fan with a touch of a grinding tone. So its pretty annoing. I think it is either clutch or diff related but would hate to have to change gearbox if its something simpler. I put the car on stilts and spun the wheels. Ill try put a video up as there seems to be a lot of play/slop in the diff.

Where are you based?There are several reasonably priced gearbox`s on here.

 

[Nicholas_taylor]

Australia, replaced a gearbox already. Had it sent from europe and changed it myself. I remember alot of swaring and skin lost on fingers lol.

 

[STEVE.M]

Australia, replaced a gearbox already. Had it sent from europe and changed it myself. I remember alot of swaring and skin lost on fingers lol.

Well that`s scuppered my plan to recommend you to a local CS specialist.
Could you get your old box refurbed locally & refit it?
I guess you have already checked the clips that hold the CV boot`s are sound?

 

[Gus]

I had this scraping noise, it would be there when driving but disappear when you pushed the clutch pedal in. it got progressively louder as weeks went on. driving slowly at 30mph it was loud but then going faster, say 70mph it wasnt as bad (could be road noise and engine drowning it out)
Turned out to be the gearbox so had that swapped and had a new clutch at the same time.

 

[Gus]

Where in Australia are you?

 

[Nicholas_taylor]

In tasmania, which makes things even harder lol. Yea i checked them it seems like theres grease escaping near both wheel hubs but more on passanger side. Is this spring noise normal?

 

[STEVE.M]

Australia,

Probably a good idea to put Australia as your location on your Avator.

 

[STEVE.M]

In tasmania, which makes things even harder lol. Yea i checked them it seems like theres grease escaping near both wheel hubs but more on passanger side. Is this spring noise normal?

Ah Tasmania would be more informative.
Sorry the vid has no content,but any suspension spring noise is abnormal?
Grease must be escaping from CV joints,check the boots on full lock for splits.