2005 - Buick LeSabre Shake at 70+

My car started to shake at 70. Even at slower speed the front end shake can be noticeable. I took the car to my Mechanic and he replaced a Control Arm. Shake still there. I took it back - he said the Driver side wheel was out of balance - he fixed it - shake still there and it’s frustrating. What could it be. Only clue I can offer, perhaps not related is my ABS system is not working. The light always comes on when I hit bumps. I’m not interested in paying 800 to fix ABS. What could be causing the shake.

Lots of things, bent wheel, bad bearing, broken belt in tire, other bad front end parts. Take it to a good front end shop.

The front wheel bearings in your vehicle also include the wheel speed sensors for the ABS.

https://www.rockauto.com/en/moreinfo.php?pk=8322572&cc=1430844&jsn=493

If the bearing wears out, it can cause a vibration at any speed, and cause the ABS light to come on.

Tester

A worn halfshaft can also cause a shake along with a broken motor/trans mount.

An additional thing to look for.

These cars are very sensitive to tires. Balancing the tires may not solve the problem. A road-force machine to measure contact force run-out may be required. Higher end dealers and tire shops have these. Also have the engine mounts checked. The tire force imbalance on these cars car set off an engine bounce, especially in older cars with bad engine mounts. They are fluid filled mounts and may have leaked out…

One thing you can do is to switch the front and rear wheels. If the vibration moves with them, then you know the issue is with a tire or wheel.

A square tire can be balanced. How old are the tires? Any tire can become defective, but once tires get beyond 4 or 5 years old they are especially susceptible to going “out of round.” Internally, the tires’ construction can deconstruct. They can still be balanced, but will continue to cause shaking at high speeds and low speeds, too.

When they are bad enough, an alert driver can discern a very subtle side-to-side wobble (usually from front or from rear) at low parking lot speeds.
CSA