Between at trip to the JLS farmers' market and the A's game I managed to stop at 22nd and International to check out the Sinaloa taco trucks in the parking lot of the taqueria of the same name. For the old time Oaklanders here, that's the site of a former A&W drive-in.
No luck on finding regional specialties -- the menu was standard Oakland (I was amused to note that tripas was translated as "chitlins" on one menu). I got what is now the official benchmark taco for this project: an al pastor. The guy ahead of me got the cabeza, and it looked good: nice chunks of tender-looking beef.
The taco was the best yet: a little spicier than the previous versions (this one came with green salsa already applied) and good corn flavor from the tortillas. I also got an asada burrito to take to the ballgame.
Since the prices for these trucks also seem to be standardized ($1 tacos, $2.50 tortas and burritos) I wondered why the burritos here were $3.00. The mystery was solved when I realized the burrito came with crema and cheese, which is usually extra on the other trucks. It was a good burrito, but not great. I was particularly pleased that the tortilla was sturdy enough to withstand two hours in a tote bag without dissolving into a soggy mess. This may have to do with the fact that the although the rice was nicely moist, the carne asada doesn't add extra moisture. The main complaint I had with it was that it seemed to have been assembled in such a way that there was salsa and crema at the ends, but the middle was drier and blander. The first bite and the last bite were the best!
The Sinaloa Taqueria itself claims to specialize in seafood, although if my rudimentary Spanish is correct, the special of the day was fried chicken ("pollo frito"). Why it has two of its own trucks in its parking lot is a bit of a mystery. It does mean that customers have access to their covered outdoor tables and restrooms, though.