Ummm, this thread is less than a week old....and I must have missed the part where I said i was in a hurry...

This should not have been a boring thread and had much potential since there are so many
owners on here who love their cars enough to want to know more about them and even do a few DIY projects from time to time...

read wot i sed
no worries
wish u well
I need to get a lil fast car I think, miss my Loti

So I dropped the car off at the dealer yesterday for some warranty work and was going to have them change out the fluid with the ATE Blue since they only charge $120 (my time for a tedious job like this is worth more than that) and the tech informed me they will only flush and replace fluid if it needs to be done. As long as it is clear and honey colored, there is no reason to perform this service. I pointed out this was the original fluid. He said fluid never need to be replaced unless they've gone bad. I have heard this position before on the age old question: to change or not to change...but never from a service department.

What do you think?

Best find a new mechanic. The appearance of fluid is a poor indicator of it's condition. Having said that, the mechanics of how fluid becomes 'contaminated' and 'needs' to be changed seems to be rather vague.

Are you suggesting the Jaguar dealer service department does not know what they are doing?

It can get right through the hoses and seals. Sounds weird but true. Its amazing what water vapor can travel through. If you look at perm ratings, rubber is permeable.

That's not what I said. Go mix some fresh brake fluid with water and shake. let it sit for a few days and tell me if the colour has changed dramatically. In re-reading the entire thread, I now remember the discussion about the super DOT 4 not being a recognized or certified category of fluid.

Jaguar recommends replace brake fluid every 30K miles OR 2 years.
Read TSB 3-179 second paragraph.

Jaguar brake fluid since the late 1990s has been Super Dot 4 in Green metal cans (500ml) or red plastic containers since about 2005.

bob gauff

bob gauff

Ummm, you said "best find a new mechanic" which would suggest you were saying the Jaguar service department is in error and therefore they do not know what they are doing, which was my response/question.

If you meant something else, I am sorry and would appreciate a translation (English is my second language)

Hmmm, mine is a different model than listed on the TSB, but I will alert the Jaguar dealer to this.

One possible scenario I suppose is the Jaguar dealer is talking customers out of routine maintenance with the hopes this will cause more expensive failures down the road?

By the way the Jaguar branded Super DOT 4 fluid is only $10 and takes 2 bottles, according to the service department anyway.

There are 'know-it-alls' in all professions. Just because someone works at a dealer does not mean they are good mechanics. I worked at a Jag dealer for years and saw some fairly $hiity mechanics come and go. Sometimes they are just young and need to learn and some are older 'idiots' that should find some other line of work!!!!!

Brake fluid should be renewed EVERY 2 YEARS!!!!!!!!!!!!!!!!!!!!!

bob gauff

This is more in line with my thoughts:

The individual mechanic may be confused, doesn't mean they're all that way.

Whether your brake fluid is indeed contaminated is another matter. I don't know what magical thing happens to it at two year intervals.

Fair enough...

In the United States, all brake fluids must meet the motor vehicle brake fluid standard. Under this standard there are three Department of Transportation (DOT) minimum specifications for brake fluid. They are DOT 3, DOT 4, and DOT 5.1. These are the three types. That's to make it easy to find brake fluid just about anywhere.


Please refer to my previous post regarding 2004 XJ Vanden Plas Complete Brake Service. The top of the master cylinder clearly indicates DOT 4 on my Jag as required for vehicles sold in the US. I flushed and refilled the entire system with a quart which cost about $8.00 at Autozone. I am sure two 12 oz. bottles would do it. Valvoline Dot 3 &4 Synthetic ($3.99-12oz or $7.99-32oz.) or Prestone Dot 4 Synthetic ($4.89- 12oz.) surpasses specifications SAE J1703, FMVSS No. 116 and DOT 4 Motor Vehicle Brake Fluid at Autozone parts stores.


They are compatible with all braking systems requiring a DOT 3 or DOT 4 fluid. Mixes well with conventional fluids. High dry boiling point up to 480ºF reduces the risk of fluid evaporation & possible brake failure.

The fluid is easy. Bleeding's the hardest part follow the attachment in my post and save a lot of money. Don't forget to reset the parking brake system. I am not racing at Road America, just driving around town. Love the car.

There's also DOT 5, frequently call synthetic brake fluid, even though all brake fluid is synthetic. Dot 5 fluid is not interchangeable with DOT 5.1 or any other fluid as it is silicone based and not polyethylene glycol like the others.

Glycol based fluid is HYGROSCOPIC. It absorbs water from the atmosphere and the higher the humidity, the faster the rate of deterioration. The 2 year recommended renewal is an average that the manufacturer calculates to keep the system functioning properly without damaging system components.

bob gauff

Very good summary!

There are several schools of thought from manufacturers about the service intervals for brake fluid.Jaguar recommends changing at 2 year intervals, other manufacturers such as Ford do not have a change interval at all. There are test strips available for testing the condition of the fluid. If you want to change the fluid every 2 years that's fine.

More than well aware of this and as I asked before, how does moisture get into a sealed system?

I got the fluid and was going to do it myself but when I found out Jaguar only charges $120 I figured I would have them do it. But when the service writer, who has been there at least 4-5 years said the Jaguar techs will only change the fluid if it is bad and been contaminated in some way, it gave me pause. A friend of mine who drives his Mercs 100,000+ miles every 3 years says he never changes any of his fluids except oil & cooling system, FWIW.

The ATE website explains the difference between their Super Blue Racing DOT 4 product mentioned in this thread and their version of the Jaguar specified Super DOT 4 (ATE SL.6).

In summary, the ATE SL.6 product has half the viscosity of the other DOT 4 fluids, and has a lower boiling point than the racing intended DOT 4 fluids.

The SL.6 is intended for electronic braking and stability control systems.

In other forums, drivers that reported harsh ABS activation with typical DOT 4 fluids found much smoother ABS activation with the low-viscosity Super DOT4 (ATE SL.6) brake fluids.

Here's a link to the ATE site:
ATE -ATE Brake Fluid


Jeff