what type of fluid should I use for a stock 110 coupe system? It's all new parts - MC, calipers & wheel cylinders, hoses, etc...

Wasn't it a DOT 4 before - the other day i went into an O'Reilly's and all they sold was a newer DOT 5 silcone, what's recommended factory spec?

thx.

evan

I don't think I would ever use DOT 5. If I'm correct, thats for old school domestics. Don't quote me on that, I'd have to check on a bottle at work tomorrow.

I'd use a DOT 4 fluid. Same as DOT 3, but with a higher boiling point.

be careful with dot 5 as its silicone based and isnt compaitable with most other fluids (if theres any left in your system)

dot 3 dot 4 and dot 5.1 are all compatible.

SAE J1703a was the factory recommendation for both brakes and hydraulic clutch.

The Oreilly's auto parts store by my house has DOT 3 brake fluid in stock.

DOT 3 meets specifications of SAE J1703a and FMVSS 116. DOT 4 has higher boiling point, but absorbs water more than DOT 3, so unless you have a problem with overheating brakes...

As Ange said DOT5 is silicone based and not compatible with other fluids. But there's another more important reason not to use it. All the other DOT fluids are hygroscopic, which means they absorb water moisture. This might sound like a bad thing, but it's not.

The silicone based fluid doesn't absorb water, so the water allowed to pool in low areas in the system, which means it can cause rust in those areas.

Your supposed to change brake fluid once a year anyway, so the water will come out, but a year is long enough for rust to occur and damage stuff...

DOT 3 it is then. I looked thru the factory service manual & couldn't find the spec so thanks all. My concern was the silicone wasn't compatible with older system rubber components.

Who the hell changes their brake fluid once a year anyways