I need to replace the front sway bar bushings but I need the diameter. Looking to use energy suspension bushings.
A cheap one is maybe $5~10, more than adequate for rough measure like round bar OD. Or get a decent dial gauge style for $40~50, you won’t regret it. Avoid digital; they CAN eat batteries. The high end ones might be ok, but who knows.
There is a formula, which I don't know, where you can wrap a piece of paper around it, mark it, then measure the length of it and apply the formula to get the circumference. You could also us a cresent wrench over it, tighten it and then measure the gap.