Car Shaking Causes and Solutions
Very seldom do we get customers that go to a tire shop to get their new wheels installed and the shop will tell them that one of their wheels is bent now this may happen from time to time but most of the time it's just a tiny slight hop on the outside edge when in reality they should be looking at where the tire bead sits aka barrel bumps. When a wheel is cast one of the first processes is heat-treating the wheel or quenching, this process is when they take the castings and put them in a big oven once the castings reach the right temperature they are cooled by rapidly dipping them in a large tank either filled by water or oil. During this process, the metal molecules expand and shrink removing porosity this hardens the metal and gives it more strength. This also may warp the casting slightly if at not all, after that the wheels move on to the machining processes. One of the processes is the truing phase where the CNC machines shave metal off the mounting pad making it flat and true, lug holes and center bore are next. Then it goes off to the next step the outside barrel so there will be some small casting imperfections but with strict tolerances and sometimes could be mistaken for a bent wheel but can easily be balanced. The photo below is where to look to see if your wheel is straight.
Other times tire shop do not calibrate their balancing machines as often as they should. Machines should be calibrated every 200-250 tire balances. So you might want to ask when the last time they have calibrated their machine before giving them the job!
Also, the type of balancer is essential as well, road force balancers are the best in the business now because it mimics the wheel and tire as if it was on the road. Another important factor is the type of mounting cone the shop uses conical cones were best once upon a time and are most common in every shop, but a lug speed plate simulates how the wheel is mounted to the car, so this with a road force balancer is the best way to go for now. Also, tires even if they are new can also have imperfections causing the tire and wheel not to balance right so it could be a combo of the two when this happens some shops will switch a tire to a different wheel and tire that balanced well to see if that was the case.
You also want to check if the wheel needs hub rings if is a custom wheel or an OEM wheel that wasn’t used for your year make or model if Proper lug nuts that match up with the wheel, a ball seat lug nut or bolt has to match a ball seat wheel conical for conical and so on. And please go to a wheel shop, not an overall general mechanic unless they are good at installing custom wheels, don't get me wrong I’m not saying general mechanic shops do not know how to install wheels and tires, but if you visit your general doctor about a foot problem he is going to refer a podiatrist.