So after a few weeks of waiting, the H&R swaybar arrived. Specs are 19mm H&R 71460. All the retail sites say that it is supposed to for the E60 M5 or sedan but the box says "All E60" and it fit the E61 perfectly.
Oooohhhh, the pretty color!
I eyeballed it and it looked like it was the same shape as the OEM bar but until I had the stock bar off I could not be sure.
The weather here has been weird. 70s last week, then we got 8" of snow Monday night into Tuesday. I finally felt like turning wrenches today after work so I did the install.
I used a T30, a 16mm pass-through socket, and an impact wrench with 18mm (more on that below), 16mm, and 13mm sockets, a 13mm combination wrench, and some Energy Suspension grease (
I made a HUGE mistake. Don't do this. I thought that the hole in the middle of the endlink was a 4mm allen but it is really a T30.
This picture shows how to use a 16mm pass through socket and a 3/8" socket wrench to hols the endlink bolt while spinning off the 16mm nut, but note that I had the 4mm allen on here. Don't do that-0 use a T30.
After partially stripping the inside of the endlink bolt I had to remove the whole endlink by smacking the 18mm nut with the impact wrench, then I was able to get some good pliers on the endlink shaft to hold it while I hit the 16mm nut with the impact, spinning it off.
I was able to replace the nut and tighten it down as well despite having slightly messed up the inside torx head.
Here is the H&R bar:
Comparison with the stock bar:
Endlinks and brackets on, with a liberal application of the Energy Suspension grease:
I used the middle stiffness setting. I did a short drive and made some left and right turns. No funny noises and the back end feels fine. I will do more testing under load conditions over the next few days and report back.