I have Lucas Premium Synthetic Dot 4 and it says its compatible to all other Dot 4's. Dot 4 is Dot 4. That being said I vacuumed mine when doing the change.

 

I vacuum all mine out with a mit e vac.

 

I recently bought a Pneumatic bleeder from BikeMaster. Works good. Just pull the trigger and it has two lines for the dual front calipers.

 

By definition, any DOT4 will be compatible with others, that is what specs like the DOTs are there for. So YES they will mix!

 

This is your answer....

If it is labelled DOT 4, it's glycol-based, and will blend/mix with any other glycol-based brake fluid.

HD's new brake fluid is most likely nothing "new" .... probably just some slight tweaks to the formula, to affect the boiling point..

Not sure how much they can really affect the moisture part of the equation, glycol-based fluid will absorb moisture...

 

Thanks guy. Didnt get to it today anyway but will definitely do it mid week

 

Shoot for Wednesday......saying 68* in my neck of the woods so your temps must be getting right up in the same range.

 

+ one on the “Mighy-Vac” if you can grab one. It’s a great way to actually pull out the old fluid and ensure you’ve got actual fresh fluid.

Back some time ago when folks had to maintain their vehicles it was pretty much an event done every two to three years with the old drum brakes. We moved away from that interval because of more effective disc brakes. Subsequently we’ve gotten “lazy” with our routine maintenance.

Ask someone under 30 if they know what brake fluid is in their ride and stand back and be amazed.

 

No problem with the mix of DOT 4's, but this will keep it at a minimum:
Using a cheap turkey baster, remove all brake fluid from the reservoir, refill with the new type fluid. THEN Mity vac fluid down and out the bleeders, keep filling the master with the new type fluid as to not run out of fluid. When new fluid is all thru the system, proceed to the other and repeat. Same way with speed bleeders.
I always start my bleeding procedure this way, it is more effective in less time.
Otherwise, many folks just move old fluid down the line, and put new fluid in the reservoir.
Think about it...

 

should be in low 50's on Wednesday Dawg but 30's again Thursday. It coming...Sun feels more intense every day even when its 20. Its coming for sure