Most minor, single mouth ulcers are caused by damage to the mouth, for example by accidentally biting the inside of your cheek while eating, or from a sharp tooth, food or filling.
I have a 2005 Honda Element. The owners manual states the brake fluid should be replaced every 3 years. When I asked the dealer to replace the brake fluid, they said it was going to cost $190. I told them last time they did it, it was only $27.
Our recommendation: A conservative rule of thumb is that a car should get a transmission fluid service every 40,000 miles. If you notice any fluid underneath the car, get it inspected as soon as you can. Changing your transmissionâs fluid regularly will greatly extend the service life of your vehicleâs transmission.