I need to top off my brake fluid and the Jag manual specifies "Super Dot 4." All the local auto parts stores seem to only stock regular Dot 4. I bought a bottle of Castrol GT LMA synthetic fluid that says it exceeds all Dot 4 requirements. Is this safe to use?

http://www.castrol.com/castrol/sectiongenericarticle.do?categoryId=90122...

Again, I'm not doing a full flush of my system, just adding a little to the reservoir.

Thanks!

Submitted by stevejag@sbcgl… on Mon, 12/20/2010 - 16:59

George,

The bulletins would be #12-05 for Sedan and #70-24 for Sedan/XJS combined.

noctilux,

I guess from a technical standpoint that is correct; but I will give you my thoughts and experience on it anyway. My experience at the dealership has been that it is in fact preferable to stay with the Super Dot 4 fluid. We for years have kept owners on a program of changeing the brake fluid at two year intervals. I can say catagorically that since the advent of Super Dot 4, the brake fluid we change has always been cleaner and had FAR LESS moisture accumulation than with Dot 4 fluid. On top of that, I have never had to replace a caliper for internal rusting, IF, it has been on Super Dot 4 fluid and, IF, it has not been more than 2-3 years since the last change.

Now, remember I never said this, I once brought this very subject up with some technical folks and their comment was, "discoloration was "legalese" for moisture accumulation. The legal dept. would not sign off on "moisture accumulation" in a brake system". Our legal system at work.

What, did I say something.......I don't think so.

Bear in mind that I won't be surprised if someone posts behind me saying I'm full of crap. That's just the way it goes. Take it for what it is worth.

Cheers,

Submitted by echorun@hotmail.com on Fri, 12/17/2010 - 01:30

Steven - that makes it sound like standard DOT 4 is fine in terms of safety and performance, but it may cause discoloration. Assuming the color of the brake fluid is not a concern, shall I proceed to use the standard DOT 4?

Thanks!!!

Submitted by stevejag@sbcgl… on Thu, 12/16/2010 - 14:55

Below is the text from a Technical Bulletin in 1996 explaining the Super DOT 4 brake fluid introduction. Super DOT 4 was specified until the introduction of Shell ESL brake fluid for 2006 and later models.

New Brake Fluid Specification ÔÇô
Super DOT 4

[this particular bulletin applied to X300 sedans, others applied to XJS, Etc.]

ISSUE:
All vehicles beginning with the above VINs use Super DOT 4 brake fluid. This
brake fluid has been specially formulated to eliminate possible discoloration that
may occur between normal service intervals. The supplier was aware that the
brake fluid could change color in service and developed this brake fluid to avoid
unnecessary customer concern.

ACTION:
NOTE: Use only Super DOT 4 brake fluid in vehicles from the
above VIN numbers. Regular DOT 4 should not be used since
discoloration may occur. Any other brake fluids (DOT 3 or DOT 5)
cannot be used in these vehicles under any circumstances.
Super DOT 4 may be used in any previous Jaguar vehicle.