Is it the thrust bearing or not?

[RayT5-R]

Hi peeps my T5-R is making a weird noise and need to know if it's the thrust bearing or not.When i'm driving along just tickling the throttle it's fine but when i floor it the noise starts and then when i reach about 4000rpm it disapears.Any ideas:B_thumb:

[nobananas]

Hi. Usually a clutch release bearing will be noisey at all times. If you sit with the car ticking over then press the clutch you will here the release bearing whirring or grumbling if it is worn. When you release the clutch the noise should go away. It sounds more likely that you have a worn diff which is only audible under heavy load (like accelerating). When 'trickling' along in slow traffic does the car feel a little 'clunky' as this is another sign of excessive backlash in the diff. Mines exactly the same and has been for years ! It might be an idea to check your gear-oil level is correct as the driveshaft oil seals often start to weep loosing oil over a long period of time.

[RayT5-R]

Hi. Usually a clutch release bearing will be noisey at all times. If you sit with the car ticking over then press the clutch you will here the release bearing whirring or grumbling if it is worn. When you release the clutch the noise should go away. It sounds more likely that you have a worn diff which is only audible under heavy load (like accelerating). When 'trickling' along in slow traffic does the car feel a little 'clunky' as this is another sign of excessive backlash in the diff. Mines exactly the same and has been for years ! It might be an idea to check your gear-oil level is correct as the driveshaft oil seals often start to weep loosing oil over a long period of time.Hi buddy it's right what you say the noise is only audible under heavy load like when going slow in 2nd and then flooring it but once it gets to higher revs the noise goes.I'll have to check gearbox oil level,but will this make the noise stop if the oil is changed or do i just have to put up with it for now.Cheers Ray

[nobananas]

When I bought my 850 the bloke I purchased it from claimed that the massive amounts of oil on the underside of the car was from the driveshaft oil seals that he had since replaced. I concluded that it had run low on oil at some time thus causing the worn diff. I have since replaced the oil and it's made very little difference ! If your gearbox oil level has been run low for a while then the damage has probably been done but changing the oil couldn't hurt. Diff whine often changes pitch over different vehicle speeds but if the noise is changing with engine speed then the problem could be input shaft bearings etc which run at engine speed.

[RayT5-R]

When I bought my 850 the bloke I purchased it from claimed that the massive amounts of oil on the underside of the car was from the driveshaft oil seals that he had since replaced. I concluded that it had run low on oil at some time thus causing the worn diff. I have since replaced the oil and it's made very little difference ! If your gearbox oil level has been run low for a while then the damage has probably been done but changing the oil couldn't hurt. Diff whine often changes pitch over different vehicle speeds but if the noise is changing with engine speed then the problem could be input shaft bearings etc which run at engine speed.Noise stays the same no matter what speed i do until i reach the speed were it stops,anyway booked in friday morning for gearbox oil change will let you know how i get on.Thanks for your input very helpful:)

[Carl]

Ray,

I've got the same issue on my 850 GLT 225K, this was the main reason for buying my T5, thing is I would like to locate it on the 850. The noise comes in at about 1250 rpm and then goes as soon as 2k is reached. So far I found that the bearing supporting the horizontal drive shaft across the back of the engine may have been a little stiff, as soon as I pressed some grease into it I noticed that I had some diff whine, so what I'm now wondering is whether this bearing was near seized for a lot of miles thus giving the diff a lot of unevan wear. I did notice this noise in a mates V70 Ok early stages but still there.

I am considering getting a box from a breakers but - would it be any better?