2010 dts platinum wrapped in 245/50/18 99 V rating primacy mxm4 tires. One got stabbed real bad this morning called all around people kept saying Monday. ( it's friday) so finally found a dealer that could get one same day. Got it done but I notice the new primacy is a 245/50/18 100 H rating.. is this a big issue? I assume not but I'm not expert
Unless you plan on routinely driving the car at over 130 mph I would not lose much sleep over the H-rating. There is no way on earth that your car would ever reach the V-rating of 149 mph, anyway. Either vehicle speed limiter (tire rating on the driver's door sticker) or plain old drag will prevent that.