Control arms hold front wheels, allowing up and down movement. of the front suspension. The control arm is an important part of the front suspension. It connects the steering knuckle (the part that holds the front wheel) to the vehicle's frame or body, see the photo.
Often, installers use grout in place of caulk for these reasons: 1  The caulk may not exactly match the grout color.  Even when the caulk exactly matches the grout color when installed, it may not match six months later (caulk will age differently from the grout).
Short answer is no, you don't NEED to seal the grout. Grout sealer is one of those products that manufacturers try to sell people that really aren't the best idea in the world. The pitch is that it will prevent mold forming. Well, that is only true in the very short term.