Brakes and oil pressure!

[TigerDale]

Yesterday I had been driving around town for about two hours, naturally getting down on the accelerater every now and then. I noticed a drop in oil pressure:confused , from just under maxed out (normal at 70mph) to around mid way on the gauge. I decide to pull over to take a look under the hood but when I stepped on the brakes the pedal went freely to the floor :eek and the brake light came on. I pumped the pedal and some tension built up so I could stop and the brake light went out. The oil level was fine as was the brake fluid level. Nothing was leaking . To top everything off, when I got up this morning everything was back to normal. Oil pressure, brakes, everything. What could cause this? ;help Any thoughts?

 

[wilezcoyote]

How did the brake fluid look? Was it nice and clear or cloudy and dark? What condition is the underside of the master cylinder resevoir cap?

If you answered cloudy and dark and the cap is all slimey and deteriorating then you might have a serious problem.

EITHER WAY, GET THE BRAKES CHECKED IMMEDIATELY!!!!

Remember bones and fiberglass don't bend when struck by a 18 wheeler truck doing 60 mph, they shatter.

I got my 90 model about 6 months ago and the brakes started acting up intermittantly about a month after I purchased it. Sometimes the pedal would be hard as a rock and other times it'd flop to the floor board. One night on a dark country road they failed completely. Needless to say, I found out exactly how well a Corvette can handle.

I took apart the master cylinder and all the rubber seals, the resevoir cap, etc... had turned to goo! The interior of the flexible lines and the caliper piston seals were the same way.

I asked around about what could do this and got two possible scenarios. The first was really old stale brake fluid breaking down. I have the maintenance records from the second owner of the car. He had the system flushed regularly. The last time was a year ago.

The second possible scenario happens when 2 different types of brake fluid are mixed. It seems that the previous owner had taken the car to the local Chevrolet dealership for an oil and filter change about a month before selling me the car. They checked and topped off all the fluids in the car. I strongly suspect that they put the wrong kind of brake fluid in it. The fluid looked ok when I checked out the car prior to purchase.

Well about $1600 later I have replaced everything but the booster and the hard lines which I flushed out 3 times. The brake rotors were about shot so I went ahead and bought a whole new setup from Baer Brakes. Stopping is no longer a problem. I really like the way the cross drilled and slotted rotors look too.

 

[TigerDale]

Thanks for the reply! I am going to go ahead and replace the master cylinder and fluid first. It seems the majority of friends I have had look at it seem to think this is the best place to start. The fluid is a bit dark but not cloudy, and the bottom of the cap isn't slimy. They seem to think some fluid might be slipping past the seals. Believe me, it will not be driven any more until we identify the problem. Thanks again.