Sad news, the X5 broke last night
I was driving it home from work and everything was fine but as soon as I turned into my neighborhood I heard a loud grinding and the X5 stopped moving. Now whenever I put it into D or R it makes a horrible metallic grinding noise. I'm thinking it's either a bad torque converter or a bad transfer case. When I pushed the X5 down the street to park it I heard quite a bit of grinding noise, even with the transmission in neutral. There are no codes or check engine lights, and the transmission shifted perfectly fine right up until this happened.
I made a video about it for my YouTube channel, which you can see here:
https://www.youtube.com/watch?v=ZHm9oi-jAng
The grinding noise can be heard at 0:42. It's quite loud.
Thankfully this happened only a few blocks away from my house, so I didn't need to call a tow truck. I parked the X5 on the street last night and this morning I went to Harbor Freight to buy a tow strap. I dug my 540i touring out of the garage for the first time in like a month and that's what I used to tow the X5 (you can see that in the video around 4:30). The 540i did just fine with the towing, while my girlfriend steered the X5 and applied the brakes. The X5's engine still runs perfectly fine so she had power brakes and steering.
I'm going to jack up the X5 on four jack stands tomorrow and run the engine with the transmission in gear to see what's causing that awful grinding noise.
Depending on what's broken, this might be the end of the line for this X5... If the transmission itself is bad then fixing it would cost more than the X5 is worth, unless I just sourced another used 5HP24 with a questionable history. Plus isn't the 4.6's transmission a little different from a standard 5HP24?
Worst comes to worst I can make all my money back from parting out this X5, and I can pop the freshly rebuilt 4.6 engine into my touring since it's a plug and play swap (aside from swapping the oil pan/oil pump/oil separator).