Originally Posted By: Wolf359
Originally Posted By: Smoqueed
The bottles don't look entirely the same, and I doubt the Autozone "DOT3" actually has those specs. I would need to go there and double check the bottle itself, sometimes they mix up stuff on the website. Regardless, unless you're tracking the car, using super high boiling point brake fluids is kinda pointless. Most standard DOT3 will work just fine for 99% of people. For a little added protection during spirited driving, I use Valvoline DOT3/4. It's like $6 or $7 for a 32 oz bottle at Meijer. Claims 480F dry and 311F wet boiling points for only a little more than a 32oz bottle of standard DOT3.
Looking back at the autozone website, their 32oz of Autozone fluid has the same specs as the 12oz bottle. Maybe it's not a fluke. If not, that's a terrific price for that level of boiling protection. Also took a look at that Bosch brake fluid. Looks like some super stout stuff. Plus I really like metal cans for brake fluid. However, I wont spend $15 a quart for brake fluid when I've never had problems with the $7 a quart stuff
Mercedes has some weird spec that calls for Dot 4 plus, not sure what the exact boiling point numbers should be, but people are using Pentosin Super Dot 4 which they claim meets the spec. In that case, it's a 509 boiling temp with a 319 wet boiling temp. They do call for a 2 year brake bleed as standard maintenance. Pentosin is about $14, but it looks like Castrol Dot 3/4 might also meet that spec and if that Autozone brake fluid is real, it would also seem like it'd work and it'd be much cheaper, it should really be labeled a Dot 3/4. I think the Valvoline Dot 3/4 has a lower boiling temp.
The Valvoline dot 3/4 does have a lower boiling point than the Autozone fluid (according to their website). If it is true, it would probably be excellent for applications requiring super dot 4/dot4+ or whatever they want to call it. Now I wonder what the viscosity actually comes out to. If it somehow worked as a dot 4 + and dot 4 LV, that would be insane! I'll have to remember to check if I ever stop at Autozone. The closest parts stores to me are Oreiley's, NAPA, and advance. All about 5~ or so miles from me. The closest Autozone is about 20 miles away. Not a huge distance, but it really makes it my least visited parts store.