Dub Davis, or WD-40, is loosely connected to the Ballas and is a relative to Curtis Davis. He got the nickname of WD-40 for being "slick af."
Dub Davis grew up in Los Santos, on Grove Street. He enlisted in the military and flew med-evac helicopters during heavy combat in the Vietnam war. After the war, he returned to Los Santos and fell on hard times. Unable to find work, and unable to afford medication for a variety of mental and physical maladies, he turned to street drugs. After a lengthy period of addiction, he committed to sobriety.
He lived with family and took care of his nephew, Curtis Davis, and his niece, Shaniquaqua. He also took care of many children on Grove Street, whose parents needed to work and couldn't afford childcare. To many of them, he is still "Uncle Dub". He has said that some of the girls whose diapers he changed grew up to be strippers at the Vanilla Unicorn, so he avoids going there.
In recent years, Dub has shown symptoms of increased mental illness. Curtis was shot and killed by Trooper Johnny Dazzler in connection with a hostage situation, high-speed chase, and gunfight. Dub was informed of his nephew's death by the San Andreas State Police. Still, Dub often says he is looking for Curtis or waiting for him to come home. When the memory of Curtis' death returned to him, he was emotionally crushed. In his pain and anger, he blamed SASP for killing Curtis and actively tries to discover which officer pulled the trigger so that he can get some form of revenge.
Because he can't afford a proper burial and doesn't want him to be cremated, Dub took Curtis' body and a hearse from the morgue and tried to take the body someplace for a burial. He was stopped after a lengthy high-speed chase by Trooper Kira Light and Trooper Kurt Leonard.
Dub also forgets about his commitment to sobriety. When he is not looking for Curtis, he's often looking for baking soda, explaining that he can make crack by cooking cocaine with baking soda. He also constantly forgets that the 24-7 convenience stores in town do not carry baking soda and tries to buy it there anyway.