Is my diff completely done?

[Mattn1192]

Driving home I noticed this out of nowhere. There’s almost no power (I have to really step on it to get the car going) and grinding noise out of nowhere... Did my Diff just take a shit?

[Cbouts]

well, if the sound is coming from the back of the car and you see no other visible damage, it certainly could be. I would image if the diff truly broke, you wouldn't get much, if any, movement no matter how much gas you give it.

Either way, it doesn't sound fun.

[lemoose]

Start with the driveshaft

[Mattn1192]

The car also pulls right when trying to accelerate.

[lemoose]

The car also pulls right when trying to accelerate.

Check right halfshaft too

[sapote]

I don’t think a bad diff can cause this. Check the diff output flanges to see how loose they are, and the output drive shafts.

[Mattn1192]

Start with the driveshaft

Sure hope it ain’t the driveshaft.

[sapote]

Also check brakes for seizures at each wheel.

[Obioban]

"almost no power" makes it sound like not the diff or drive shaft to me. I'd look at the half shaft and brakes (one half shaft would be snapped, which you should be able to see just by looking. A seized caliper would result in one corner being super hot, of you put your hand near the wheel, after driving).

[sapote]

Sure hope it ain’t the driveshaft.

The main driveshaft either transfer full power or none, nothing in between.
One theory: the V1 diff has the RH side output flange loose with mileage, and in extreme case the loose flange is out far enough that the spider gears cannot mesh the flange's side-gear reliably, causing grinding and slipping, but the M3 LSD clutch helped to keep the left wheel moving the car but old clutch also slipped and so driver felt lacking power, and since only left wheel had power, car pushed to the right.

[Casa de Mesa]

Do you have an infrared thermometer? I'd compare brakes temps on the rotors (point it at the non shiny parts, not the swept area) L to R sides. My gut says it's a seized caliper and you're now on the backing plate(s).

[Mattn1192]

Do you have an infrared thermometer? I'd compare brakes temps on the rotors (point it at the non shiny parts, not the swept area) L to R sides. My gut says it's a seized caliper and you're now on the backing plate(s).

Right rear axle is wobbling around when I rotate the right rear wheel by hand. Pretty sure I need a new diff.

[Casa de Mesa]

My gut no longer says brakes, LOL!

Wobbling how? Inside the diff? At the inner or outer half shaft/CV?

I had to replace the passenger side half shaft on my car at 73k miles. That's early, but these cars are harder on the passenger side axle than driver side.

[Casa de Mesa]

Make that 71k. Here is the driver side I cleaned and repacked at the same time. Passenger side was notchy as hell, driver side was smooth as glass. I went with a remanufactured OE/BMW part.

[Mattn1192]

My gut no longer says brakes, LOL!

Wobbling how? Inside the diff? At the inner or outer half shaft/CV?

I had to replace the passenger side half shaft on my car at 73k miles. That's early, but these cars are harder on the passenger side axle than driver side.

The damage