Flat spots develop on tires that sit in one place for too long, or if they’ve been sitting while they are under-inflated. I thought you have a bad tire but then I saw you changed them. Has anyone ever checked these:I end up balancing the Tires again. Didn't really help.... I got VWR Springs installed now too and had the car realigned... High speed its still not a comfortable feel.... Honestly it's not that terrible but still a bit annoying when I notice it. I might just go to the dealership but now that I have VWR springs installed they will give me crap for that and blame them even though this was a pre-spring issue.
1. The balancing of your drive shaft.
2. The torque of your bolts for your engine, transmission and dog bone bolts.
3. Broken or failing crankshaft pulley? (It’s a harmonic balancer)
4. Does your engine look like it’s straight in the engine compartment? The mounts have play and if installed incorrectly the engine can be slightly crooked in the compartment. Check the DIY instructions on ECS tuning for their motor and tranny mounts to see what I’m referring to.