Guys/Gals/DiscoMike,

I've got a 2002 DII that needs a brake job (pads & probably rotors). I am going to flush brake system while I'm down there.

I use a DOT 5 synthetic brake fluid in both of my Powerstrokes, which get SERIOUS brake workouts in due to towing, and it has performed flawlessly. However, so do most Ford products....

According to what I have read, the DOT 5 will mix with 3 & 4, and is fine for the seals in all brake systems.

Anyone who can help or has experience, please weigh in. I get this stuff in bulk through our parts supplier, and its a bargain compared to the PepBoys Castrol 4.

Yes, I have done a search. I'm dumb sometimes, but not completely stupid....

Thanks in advance for the help. Lucille says the same.......
- dc

 

You were wise to ask this.

According to general listings, DOT 5 is not compatible with ABS systems. It does buy you another 30 degrees C temp range, and it won't absorb water. If mixed with DOT 3 or 4 it could cause problems with seals.

So since you trailer, which is severe use, why not stay with something that allows the ABS which just might come in handy. DOT 5.1 might be the ticket.

DOT 5.1 is not silicone based, and is compatible with older fluids, just flush completely. It has an even higher temp rating than 5.0 (518 degrees vs "only" 500 for 5.0).

Here some more tech infor I saw on this.

DOT 5 is silicone fluid and the above does not apply. Ideally, silicone fluid should be used only to fill non-ABS systems that have not been previously filled with glycol based fluid. Any system that has used glycol based fluid will contain moisture; glycol fluid disperses the moisture throughout the system and contains corrosion inhibitors. Silicone fluid does not allow moisture to enter the system, but does not disperse any that is already there, either. A system filled from dry with silicone fluid does not require the fluid to be changed at intervals, only when the system has been disturbed for a component repair or renewal. The United States armed forces have standardised on silicone brake fluid since the 1990s. Silicone fluid is used extensively in cold climate, particularly in Russia and Finland

 

To the best of my knowledge Dot 5 is compatable with Dot 3 & 4 seals. but it should not be mixed.
I have converted all my cars and bikes over to Dot 5 and have yet to have a seal problem, some quite a few years ago. But I have always done a complete flush of the systems.
I converted my Disco over a few months ago for the same reason, I have gallons of Dot 5 why pay for Dot 4.
I have had no problems, yet

 

How about you go with what is the best fluid for your D2, Castrols synthetic DOT4, better then the Castrol Rover installed at the factory and now a synthetic. Oh, yes it is more expensive then the cheap stuff, and that is what you get, a fluid that over heats faster, absorbs more moisture, generates a softer pedal especially when hot and when burned, will take the seals right out of our ABS units.
If there is any chance of a DOT5 messing with your ABS, you don't want to use it.
The more important question you might want to ask is what are the best pads and rotors for your D2. I hope you are not going to go cheap with the pads like you are leaning towards with the brake fluid, what are you thinking about using?

 

Guys,

Thanks for the inputs. My reasoning for using the DOT 5 was simply that is has performed VERY well in my diesel trucks under severe load. Its NOT cheap, but I can buy it through my business as "truck maintenance items" and spend pre-tax dollars on it. That DOES make it cheap, relatively speaking.....

However, for Lucille, I am not as concerned about performing under load as I am with longevity of ABS components, and, based on that, maybe the DOT4 makes more sense.

The part about the 5.1 also makes sense, I'd just have to flush very well.

DiscoMike, in regards to brake parts, I have had great experience with EBC products, I use their yellow-stuff pads on the trucks, and had the green-stuff pads on my previous DII. I don't like ceramic pads in general, as I think they wear out rotors too fast, and don't stop nearly as well as the EBC.

Cleaning the truck deals with the dust issue mostly. That, and a can of brake cleaner.

Rotors might be OK with a turning, but I'll have to dig out the caliper when I get her up on the stand. If not, I'd probably end up going with either an EBC or a stock replacement. I don't really drive this truck hard enough to warrant a drilled/slotted setup. I'd also take suggestions on brake rotor choices.

If I need something pulled and/or stopped, I have 2 diesel beasts to do it, and they get better mileage than the rover anyway....

 

Did you have any problems nowaday ?Does Discovery's ABS work still fine ? Did you wash (clean) the brake circuit before filling it with silicone dot5 ?

Best Regards
Maximilian

 

I, did you use silicone DOT5 on your Disco ? Can you report your experience , please ?
Best Regards
Maximilian

 

the system is operating just fine the dot 5 have been in there just abut a year now.