I have a hollow swaybar, but I can't tell for sure what size it is. Depending on where on the bar I measure the diameter, it could be a 34mm or a 36mm. I know it is hollow.

Is there a part number stamped anywere on the bar? If not, where should I measure the bar to find out accurately what size it is?

I didn't take it off the car, so I don't know if it was on a 1LE or a WS6 bar, or just a regular car.

 

Just get some calipers and measure it. Easiest way to find out. As far as I know there are not part number stamped onto the bars.

 

Any suggestions were to measure it to get an accurate measurement? Some places on the bar measure less than 34mm, some a bit over 36mm... where should I measure to get an accurate number?

 

Measure between the two mounts. That seems to be the straightest part of the bar in most cases. Basically measure it in the middle of the bar.

 

yeap, in the middle on the straight part