Whining noise from Rear Differential under Acceleration

[jd147]

Hi I wondered if anyone has come across this. When moving the car and speeding up I get a more louder whining noise coming from the rear. When I dip the clutch in the noise goes and then comes back when re engages the gear. Any thoughts? Thank you!

[Mike41288]

Possibly a failing pinion bearing. Sadly its it is, its a real pain because I'm sure you have to remove the abs sensor in the diff to get it out. The sensor can be horrible to get out and most break unless you have patience and time.
Might be worth draining the fluid and looking at the magnetic drain plug for debris to rule anything else out. If all OK, maybe some fresh fluid could help.

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[jd147]

Hi thanks for the reply I recently just had the car fully resprayed been rebuilding it for the last 2 years! I emptied the old diff oil and replaced with Morris 80w-90 API GL5 when emptying the old fluid nothing came out of the ordinary out it looked okay so topped up until was coming out the fill plug then left it. It's a weird noise doesnt go when braking/revs are going but the whine stops when dipping the clutch. Very weird!

[Mike41288]

I know the r200 diffs usually take 75w90 but I can't see that being too big of an issue. Lots of driveline noises go away when dipping the clutch because it unloads the transmission, allowing it to freely spin without the torque of the engine. Do you know if the diff is standard or has it been upgraded with a plated diff or helical diff?

[jd147]

Hi and it's completely standard from stock from the factory. Tbh I changed all the rear subframe bushes to super pro but never changed the ones on the diff just the suspension ones all on the subframe didn't know weather this could factor in. It's definitely coming from rear gets louder when going quicker ect.

[Mike41288]

Fitting stiffer bushes will always transmit more noise, but the biggest increase in noise is from fitting solid diff mounts all round. You hear all the clunking and it can be unnerving the first time driving it afterwards.
If you could get a video of it happening, it could help determine if the sound is normal or something has gone bad