Callipers Red Paint damaged by Brake Oil?

[gtmartini]

Hello,

I own a Boxster S (MY 2000) and last week went for a brake oil change at my local Porsche dealer.

This weekend while cleaning the car I've noticed that two of the brake callipers (one in the rear and the other one in the front) have the red paint damaged, like if something corrosive has had contact with the red paint (the red paint didn't actually get off, but the shinny red colouring gave place to a dull magenta color, starting at the calliper oil hose and descending through the calliper in a irregular liquid-like shape).

I've been today at the dealer, but they say that this corrosive marks were not the result of the oil change and some subsequent brake bleeding that was not propely cleaned, and state that "Our brake oil is not corrosive" and that "we change lots of brake oil and it never happend such a thing". They suggest that this may be the result of some wheel cleaning product used to clean the wheels (:-o).

However, I've only noticed these (very well visible) marks after the oil change, and I find it difficult that they may have scaped my observation if they were result of bad wheel cleaning products over time!

On the other hand, as far as I know, Brake Oil is known to be very corrosive! Does anybody confirm this?

What is your opinion about this situation?

Thanx in advance,

GT

[Tool Pants]

Brake fluid eats paint. But, at least with the black calipers, it does not. Whatever coating is used on the calipers is resistent to brake fluid. When we bleed the brakes and then remove the tube from the nipple some fluid dribbles out of the end of the tube onto the caliper. Never seen any damage to the coating.

Do not know if it is the same with red calipers. Are you positive it was not like that before the brake fluid change. There are some S owners who have had the calipers replaced under warranty because the coating did not look good over time, but this was unrelated to brake fluid getting on them.

[gtmartini]

Hello,

Thanx for your reply.

As far as I can remember, I haven't noticed it before (and I wash my car very frequently, so I wouldn't had missed it)!

And the mechanic at the Porsche dealer also does not seem to remeber the caliper paint being damaged when he performed the oil change...

And yes, it is not hard to believe the caliper paint may be resistant to brake oil, but perhaps only during small amounts of time of contact. I begin to suspect that they may have forgotten to clean propely the oil that spilled over the caliper, and during the 3 days it stayed in contact with the paint (in other words, until I washed the car in the weekend), some corrosion may have developed...

Anyway, the excuse given by the Porsche dealer that brake oil is not corrosive starts to seem each time more supicious...

Regards,

GT

[mrmickeymouse]

Here is some info on how corrosive brake fluid can be.

http://www.ehow.com/how_112910_add-brake-fluid.html

http://www.autoshop-online.com/auto101/brake1.html

"It should be noted that brake fluid is highly corrosive to paint, and care should be used not to get it on your car's finish."

Scott

[gtmartini]

Hello,

Thank you for all your replies!

I've done some further research on the web about the corrosiviness (does this word exist in english?!? whatever... I think you get the picture) of Brake Fluid.

As far as I could understand, DOT3, DOT4 and DOT5.1 brake fluids are polyglycol based and consequently corrosive to paint. The DOT5 on the other hand is sylicon based, and does not present problems of corrosion when in contact with painted surfaces (but may present other drawbacks such as spongy feel on the brake pedal).

My question is: Is it possible that my PORSCHE dealer is using DOT5 brake fluid in my Boxster?

I would find it very strange, since it seems that DOT5 fluids are a lot more expensive than the other DOT3/4, and even 5.1, more common fluids, and that it would demand a complete and throughful bleeding and cleaning of the entire brake system since no mixture between these two class of brake fluids is advisable! I also read that some of the rubber sealants of the braking system may not be sylicon compatible and may start to degrade while in contact with DOT5 fluids...

On the other hand, DOT5 fluids seem not to be regarded as regular brake fluids, apparently being only used on specific situations where corrosion can be a major problem (e.g. Military vehicles that are parked for long periods of time, or in car museums or collections).

I got this information from several sources in the web, and so I'm not sure if I got the whole and correct picture...

Any comments?

Once again thank you for your time!

Best Regards,

Gustavo