Thread: D3 TDV6 Brake fluid options

Originally Posted by 101RRS

I just buy mine from a dealer - is the same cost as some after market fluid from Supercheap.

Yeah same. It’s just easier and not expensive.

Originally Posted by LR3 Disco Owner

And there's the kicker, ISO 4925 Class 6 states that the viscosity has to be at or below 750 whereas Class 4 is at or below 1800.
Now the ISO standard also says that Super DOT 4 should be Class 6, but both the Nulon and the Penrite don't meet the Class 6 specification with viscosities of 1231 and 1147 respectively, instead they just list that they meet ISO 4925 and don't mention the Class, could this be to deliberately mislead, as people would rightly assume that since it is Super DOT 4 that it should be Class 6?
I'd be interested to see a graph of the viscosity against temp to see how they compare at around 0 degrees as that's probably more applicable here than -40!

So in the real world of Straya what will go wrong using Class 4 instead of 6?

Originally Posted by PerthDisco

So in the real world of Straya what will go wrong using Class 4 instead of 6?

I don't know, that's the thing, saying the one is nearly twice as thick as the other at -40 degrees doesn't really mean much here, it would be more beneficial to know what the difference is at 0, or maybe -10 if you're going to the snow, but otherwise it comes down to how easily it travels through the braking system.

Originally Posted by PerthDisco

So in the real world of Straya what will go wrong using Class 4 instead of 6?

The ABS system will operate slower and the traction will be less effective. Also supposedly it’s designed to protect new types of seals used in the system.

Bosch claimed somewhere that the ABS cycle speeds were improved by over 30% using class 6 and it was developed to support traction control systems as used in the Disco etc.

Originally Posted by LR3 Disco Owner

Can you remember how much that was? As the DOT 5.1 is $30 a bottle I reckon the main dealer price can't be too far off that. My local Supercheap and Repco don't have any of the DOT 4 ESP in stock and the dealer is 180km round trip, so if I was just topping up I'd probably just go the 5.1 but since I'm going to flush it out based on other comments I'd need around 1.5L(??) which then warrants the drive.

Its been a couple of years as I bought a few bottles to last me a while but was under $20 a litre bottle (Lennocks in Canberra). I ended up going to the dealer as the exact grade of oil was not available in stock at Repco/Supercheap/Shell etc and I would have to order it and of course I needed some right then and then.

Originally Posted by DiscoJeffster

The ABS system will operate slower and the traction will be less effective. Also supposedly it’s designed to protect new types of seals used in the system.

Looks like I’ll be doing a double flush soon.

Originally Posted by LR3 Disco Owner

Unfortunately their website says they are discontinuing it and that the 5.1 is the replacement.

It is specified to meet the specs and the viscosity is right. Why wouldn’t you use it?