The bus drivers who shuttle Yahoo, Apple, eBay, Zynga and Genentech employees to and from their offices voted to unionize Friday after complaining about being overworked and underpaid.

The Compass Transportations drivers voted 104-38 to join the Teamsters union Friday, according to the San Francisco Chronicle.

The decision comes more than three months after Facebook bus drivers voted to also join the Teamsters union in November.

Teamsters representatives plan to continue to court Silicon Valley drivers, who they say are not benefitting from the overall growth in the region.

Facebook's bus drivers, who work for Loop Transportation, recently voted for a union contract that features several new benefits, including health insurance, paid time off and higher pay, according to San Jose Mercury News.

The Teamsters plan to use that contract to amp up benefits for drivers at other Silicon Valley tech companies as well, the newspaper reported.

Rome Aloise, secretary-treasurer of Local 853, told CBS San Francisco that drivers for Apple, Yahoo, Zynga and the other companies would see their wages jump from $5 to $9.50 per hour as well as have the option for overtime pay.

Genentech's spokeswoman, Lisa Slater, told CBS San Francisco that the pharmaceutical firm will "respect whatever decision is made by the drivers."

Compass Transportation is owned by SuperShuttle, which is known for offering shared rides to airports, and has a fleet of 107 vehicles, including mini-buses and full size coaches, according to the company's website.