"My arms would get really tired and I would have to stop and take rests," Brandon told KTHV-TV.
Tanner noticed, and decided to do something to help.
"He's just been a really good friend and I wanted to do him a favor," Tanner told KMOV-TV. "I just felt like I needed to do it. ... Brandon, he's just always been there for me."
But it took Tanner two years of working at a mechanic's shop to earn enough funds to upgrade Brandon's mode of transportation. He also did his research, spending a year searching before finding the right model of a wheelchair up for sale on Facebook.
Tanner presented Brandon with his new wheels during class last week, completely taking his friend by surprise.
"They came in and my face just blew up ... crying everywhere," Brandon told KTHV. "Just like, 'Wow, can't believe he did that for me.'
"I did not know he was saving up," Brandon added. "It's been my dream just to have one of these, and he made my dream come true."
Seeing Brandon's reaction was priceless, according to Tanner, who said he would do it all over again.
"Everybody keeps asking me, 'Was it worth it? Was it worth it?'" Tanner explained. "Yeah, 100 percent."
Brandon's new ride not only provides him with more speed — it's got style. One of his teachers, Ginger Wray, made customized flame decals for the fenders in Brandon's signature color, orange, and his last name is emblazoned on the back.
"It's awesome," Brandon said of his new wheelchair. But he admitted to his buddy, "I'm not the best driver, Tanner. Not yet, anyway."