2001 xTerra Brake Problem -- Need Answers

[L. Owens]

Help!

Last Winter (2003), I began experiencing some problems with my brakes on my 2001 xTerra. I have taken the vehicle to a corner shop and, most recently, to a dealer to diagnose the problem.

The problem with the brakes always happens only in frigid cold temperatures. When I hit my brakes, they do not engage. It is as if I have my foot against a cinderblock wall and pressing. I have no brake control when this happens. The vehicle keeps going, and going, and going, and going. You can imagine the peril this creates for others and me. Fortunately, each time this has happened to me, no one has been crossing the street, nor were any cars coming at the time, or the car stopped just in time. Needless to say, the dealership cannot recreate the problem and the brakes worked fine for them (of course)!!

Has anyone had this type of problem with his or her xTerra? I am at my wits end and I'm afraid. The dealer couldn't find the problem, the corner shop couldn’t find the problem, and I don't know what next to do at this point. I awoke at 4:00 a.m. this morning to the thoughts of what could happen the next time.... Any suggestions would be greatly appreciated.

[OffroadX]

Does the pedal move and then resist normally when you press it, or does it not move at all?

What did the shop and the dealer investigate? Did you leave the vehicle outside overnight with them when it was "frigid cold" outside so they could test it under the same conditions first thing in the morning before the temps went up? A heated indoor shop bay or a warmed-up vehicle that has had time for the engine to heat up nearby brake components do not duplicate the conditions, and they would not be able to duplicate the problem.

That said, I bet you have a fair bit of moisture or even a small volume of water somewhere in your brake system that is freezing solid and not allowing the brakes to operate. I'd start with a complete brake system flush and refill with fresh Castrol LMA brake fluid (LMA = low moisture absorption), plus checking or replacing the fluid reservoir cap just to eliminate the obvious potential avenue for moisture to enter the system. An inspection of the dust boots at the wheel cylinders would be prudent as well. Come to think of it, if there has been a volume of water freezing inside the master cylinder, the expansion could have damaged something that could lead to further problems later on, so if it is suspected to have had ice in it, it should be checked out as well.

Brent

[L. Owens]

Brent, you are a lifesaver!

Everything you have suggested makes perfect sense -- I wonder why the dealer didn't suggest it! The irony of it is that when I got into the truck this morning (with my former thoughts still in my head), it did it again -- this time while I was attempting to leave my driveway (thank goodness)!! When this happens, initially the brake pedal is "hard as a rock," and the brakes eventually engage "hesitantly" after a few pumps, so the "moisture in the system" suggestion makes perfect sense. The dilemma, however, is that you do not always have time for those extra pumps of the brake pedal b/4 that 18-wheeler comes to get ya or that kid darts out in front of the truck!

The dealer told me they left the truck outside overnight and the temperature was, in fact, below freezing. They indicated that they drove the car for a while with no incident, i.e., they were unable to duplicate the condition.

I am going to take your advice and have the system flushed, as well as replace the cap and check out those other brake elements, as you have suggested. Hopefully, that will fix the problem and give me some peace of mind. I will let you know how I make out.

Thanks again, Brent!

- Lydia

Originally Posted by OffroadX

Does the pedal move and then resist normally when you press it, or does it not move at all?

What did the shop and the dealer investigate? Did you leave the vehicle outside overnight with them when it was "frigid cold" outside so they could test it under the same conditions first thing in the morning before the temps went up? A heated indoor shop bay or a warmed-up vehicle that has had time for the engine to heat up nearby brake components do not duplicate the conditions, and they would not be able to duplicate the problem.

That said, I bet you have a fair bit of moisture or even a small volume of water somewhere in your brake system that is freezing solid and not allowing the brakes to operate. I'd start with a complete brake system flush and refill with fresh Castrol LMA brake fluid (LMA = low moisture absorption), plus checking or replacing the fluid reservoir cap just to eliminate the obvious potential avenue for moisture to enter the system. An inspection of the dust boots at the wheel cylinders would be prudent as well. Come to think of it, if there has been a volume of water freezing inside the master cylinder, the expansion could have damaged something that could lead to further problems later on, so if it is suspected to have had ice in it, it should be checked out as well.

Brent

[OffroadX]

Brake fluid is hygroscopic, meaning it absorbs moisture. If the system is not sealed, it will wick moisture out of the air, and the reservoir cap is the only obvious place for it to do so unless the reservoir itself is cracked or something. Anywhere else in the system and any way "in" would be a massive way out for the fluid under pressure, so I would not really worry about the calipers etc. The only reason I mentioned the dust boots on the pistons is that if they had become dislodged or torn, water could get splashed behind them and it could freeze and obstruct the piston from moving, but that's "outside" the area where the brake fluid is contained so it wouldn't contaminate the fluid. Plus I would think that the odds of ice in that area actually preventing the piston from moving would be slim, the pressure behind the piston is very strong and should easily dislodge any ice.
I'll bet the problem is occuring in the master cylinder, though it could be possible for all the individual lines to each wheel could have enough moisture to freeze solid.

Brent

[L. Owens]

Thanks, Brent! I am actually in the process of making an appointment with the dealer to have the brake system flushed (not sure if I should frequent the dealer who didn't recommend these things, though), and I'm also going to recommend some of the things you mentioned. Peradventure, they did, in fact, miss some things. I will let you know how I fair in this endeavor.

- Lydia

Originally Posted by OffroadX

Brake fluid is hygroscopic, meaning it absorbs moisture. If the system is not sealed, it will wick moisture out of the air, and the reservoir cap is the only obvious place for it to do so unless the reservoir itself is cracked or something. Anywhere else in the system and any way "in" would be a massive way out for the fluid under pressure, so I would not really worry about the calipers etc. The only reason I mentioned the dust boots on the pistons is that if they had become dislodged or torn, water could get splashed behind them and it could freeze and obstruct the piston from moving, but that's "outside" the area where the brake fluid is contained so it wouldn't contaminate the fluid. Plus I would think that the odds of ice in that area actually preventing the piston from moving would be slim, the pressure behind the piston is very strong and should easily dislodge any ice.
I'll bet the problem is occuring in the master cylinder, though it could be possible for all the individual lines to each wheel could have enough moisture to freeze solid.

Brent

[OffroadX]

Okie dokie!

By the way, no need to quote my posts in your reply, please remove it if you click "reply w/ quote" or better yet, just use the Quick Reply box at the bottom.

Brent

[L. Owens]

Hi, Brent!

You know, I was wondering about that ... but, because I'm new to the website, I wasn't quite sure how to do that. I'm looking for the "quick reply" feature at the bottom, but it's not listed as an option, so I will manually delete the quote. Thanks again for all of your help!

By the way, I don't believe I will use the same dealer to do the brake flush, etc., but I considering Carmax instead. Perhaps they'll do a better job for me.

Have a wonderful weekend, Brent! It's snowing here ... and weather forecasters are proclaiming 15 inches or more ... xTerra owners in this area are going to love that!!!

- Lydia

[Schludwiller]

The Quick Reply function is about 5 inches below this post and is a white rectangle with "Quick Reply" over it. It's below the blue thread "Related Links".

[L. Owens]

Thank you so much, Mr. Schludwiller. I have found it!!

- Lydia