Greetings,
When slowly driving in a tight-ish circle i hear some light grinding sounds coming from the rear end, it feels/sounds like its two pieces of unlubricated plate rubbing, like there is initial static friction resistance then less kinetic friction resistance. Similar to how those twisting bird calls make noise, somehow it feels/sounds like that. the grinding only presents itself at certain speeds, which made me think it was the diff. I believe i confirmed this by making the grinding noise occur and then press the clutch pedal, and the sound would go away, let off the clutch and it would come back. so engaging the driveline made it occur.
About the Diff :
I put this diff in the car about 10 years ago, i remember it being a 4.10LSD that came from the bimmershop shelfs. At one point i had to swap the backplates of the diff because the diff bushing mount cracked. i did a poor job of this many years ago and while its bolted back together it leaks more than id like. i recently did a fluid change but could not get redline fluid, i had to use valvoline 75w-140 with the LSD additive. could this be the cause? or perhaps there is damage on the inside of the diff? i just picked up a 3.73 LSD that doesnt leak that im going to swap in but wanted to know if theres any other diagnosing i could do while the diff is in the car.
Thanks!
When slowly driving in a tight-ish circle i hear some light grinding sounds coming from the rear end, it feels/sounds like its two pieces of unlubricated plate rubbing, like there is initial static friction resistance then less kinetic friction resistance. Similar to how those twisting bird calls make noise, somehow it feels/sounds like that. the grinding only presents itself at certain speeds, which made me think it was the diff. I believe i confirmed this by making the grinding noise occur and then press the clutch pedal, and the sound would go away, let off the clutch and it would come back. so engaging the driveline made it occur.
About the Diff :
I put this diff in the car about 10 years ago, i remember it being a 4.10LSD that came from the bimmershop shelfs. At one point i had to swap the backplates of the diff because the diff bushing mount cracked. i did a poor job of this many years ago and while its bolted back together it leaks more than id like. i recently did a fluid change but could not get redline fluid, i had to use valvoline 75w-140 with the LSD additive. could this be the cause? or perhaps there is damage on the inside of the diff? i just picked up a 3.73 LSD that doesnt leak that im going to swap in but wanted to know if theres any other diagnosing i could do while the diff is in the car.
Thanks!