Thought I would throw this out there. I bought a CPO Lincoln MKZ for work purposes last month. Dealership put new OEM Michelin's on it. After putting about 3,000 miles on it I was tired of the vibration it had at hwy speeds. Took it to Advance Performance Tires in Tampa, FL. Guys road forced and balanced them and it's smooth as glass now. I had one tire with 26#'s of road force which they got down to 13#. All 4 tires were out of balance too. I got to watch them work the Hunter 9700 Machine. Pretty cool machine. If you can watch the whole thing, it's worth it.
Tires ended up with 8, 9, 10 & 13 #'s of road force. And balanced. My goal was to be under 15#'s. Anything over that is excessive for a late model quality car/tire/wheel. Most High end manufactures like Jag, BMW etc I think are spec'n 15#'s max road force. May be wrong, but swore I read that somewhere.
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'07 335i Sedan, base pkg, 6spd Manual, Procede 3 V5 w/NLS, Macht Schnell Downpipes, 18" Staggered 313's w/Conti DWS's, OS Giken TCD LSD, VAC Street Diff Cover, Dinan Oil Cooler, Dinan Intercooler, Akebono Euro Pads, CDV Removed, Black BMW Grilles, Interior & Exterior white LED lighting, LUX Angel Eyes, Debadged, Blend V1 mount, Llumar ATR Tint.