Hydrastar Brake Fluid

[martyb6]

I have a 2022 GD Solitude 382WB with the 8k / disc brake option. Everything I read says to use DOT 3 or 4 brake fluid. I also read that you're not supposed to mix the two. How do I know which brake fluid was put in at the factory so that if I need to add fluid I'm not mixing the two? Thank you, Marty

[howson]

I have a 2022 GD Solitude 382WB with the 8k / disc brake option. Everything I read says to use DOT 3 or 4 brake fluid. I also read that you're not supposed to mix the two. How do I know which brake fluid was put in at the factory so that if I need to add fluid I'm not mixing the two? Thank you, Marty

I'm by no means a brake fluid expert--but a quick internet search revealed that most replies to the question suggest it's OK to mix DOT 3 and 4. (I entered "mix dot 3 and dot 4 brake fluid" into DuckDuckGo's search engine and read a few of the returning links.)

Two of this forum's "car guys" are Guest and Cate&Rob -- hopefully they will chime in if anything I've written is wrong.

A call to GD Customer Service is the definitive source to get an answer. If you call them please let us know the answer.

Howard

[familytruckster4]

Howson is correct on all counts, Dot 3 and 4 are interchangeable but like so many automotive supplies there are some application specific exotics (anti freeze as an example) that you have to be wary of. I would guess that a quick google search with the brand and model of you brake system would yield an owners manual, I would follow that documents recommendation

I noticed that E-trailer has a Q&A section where someone has asked this same question. Their reply was DOT 3 or 4 was acceptable.
There is information that says if you originally had DOT 3 that you could use DOT4 but if you originally had DOT 4 then even though DOT3 is compatible (same basic technology) that using DOT4 would yield the best results. In short it looks like DOT4 check all the boxes.

[Cate&Rob]

Hi Marty,

I concur with the recommendations here. DOT 3 & 4 are glycol based brake fluids (with slightly different viscosity and boiling points) that can be mixed. DOT 5 is the one to stay away from in a standard braking system as it is silicone based and not compatible with the glycol based brake fluids.

Rob

[Jlawles2]

Check the color of the fluid. https://en.wikipedia.org/wiki/Brake_fluid If it's clear either DOT3 or DOT4 are acceptable, if purple (verification that there was not a change that was not noted) then DOT 5.

Alternatively it appears that DOT 5.1 is backwards compatible to 3 and 4 if the system can handle the borate.