No, 27 is not too old to transfer. Schools everywhere, and definitely in California, see older students all of the time.
Be sure to look into TAP/transfer agreements between your CC and UCLA. Also look into your local CSU as a back-up plan for transfer as there is a high probability of getting into that school. (Local CSU means the one generally closest to the CCC you took the majority of your credits.)
As for the question if work plus UCLA is too much - that depends. How long does it take to commute the 20 miles? How many hours a week do you need to work? Is the work something that heavily tolls on you or are you (for example) able to do a bit of homework on the job? Is the job flexible in hours or very rigid? Are you a quick study, or do you need a lot of free time to get your homework done?
Have you ever attended school fulltime (with a solid set of classes, no fluff) while also working? How did that go?
The reality is that some small set of students can go to school fulltime and work fulltime. They have the right amount of flexibility, strong study habits (perhaps quite agile as well and able to finish study/homework faster than average), and enough other factors to pull it off. Some students, with their best diligence, can not do both school and work fulltime together. You need to assess this based on all those other prior questions.
Also check if your work schedule hours will allow for you to sign up for classes – if 80% of the classes you would need are between 9am - 2pm and you work 9am - 5pm, that will become a major problem quickly.
Also check if you can go parttime to UCLA (I don’t think you can, but don’t know for certain.)