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When I Brake, The Car Swerves

A few months ago when I got new brakes, the mechanic mentioned I should consider a brake fluid flush. Recently, especially at high speeds on the freeway, when I brake I feel my car swerve slightly from left to right in the front end. I still drive a straight line, but I do feel the movement. I think this might be related to the fluid flush–maybe something’s preventing the brakes from acting in unison?



If anyone has experienced something similar or has guesses about what the problem is, I’d appreciate the feedback.

Make, model, year, mileage of vehicle?

It could be a caliper that was on its last legs with corrosion from not changing the brake fluid for 10 years. Then the fluid change stirred the crud up and the caliper froze.

It could be some other suspension part that is worn out & not related to the brake work.

1997 Dodge Neon, automatic, 176k miles.

I got all four struts replaced last year, so I don’t think it would be a suspension issue again.

Most likely causes are constricted front hoses or front calipers, either pistons seizing up or hardware/slides not working properly. Another possibility is that the mechanic who did the front brake service reinstalled the calipers with a twist in the brake hose. This is a somewhat common mistake, especially with a rookie, and will manifest itself in the form of an intermittent brake pull. Take it back and have the mechanic check these things. Should be easy to find and fix.

Yeah, I agree with the previous posters. Sounds more like uneven brake caliper application. I have a hard time believing it’s related to not flushing or changing your fluid for 10 years. Up until 10-15 years or so ago, the brake fluid flush/change was not hardly mentioned, and the only time I saw a caliper failure was due to frozen calipers from non use, or leaking calipers due to abuse (frequent, heavy application) driving like a race car. You won’t hurt anything by changing your brake fluid, but it’s not causing your problems. The flush is a revenue generator for the business.

Did you have the brake fluid flushed?   BTW this should be done about every three years.  If you fail to do it, you usually get no indication of a problem until you try to use the brakes some day and they don't work properly or maybe not at all.

I agree that brake fluid should be flushed ever two-three years, particularly in damp climates. This has been the recommendation for as along as I have been working on cars (45 yrs).

If your problem is rust in a caliper, it is too late now to flush it, you will need more extensive work on the calipers.

Another thing that can cause brakes to pull one way is a leak of either grease or brake fluid getting on the brake pads. If that is the case, it should be addressed very soon.

Worn suspension linkage or bushings can cause the wheel to turn a bit under braking action, which can cause the car to pull one way.

I believe this car has rear drum brakes. If a wheel cylinder is leaking, it will foul the shoes and cause pulling. Also wheel cylinders can get gummed up so that one or both of the pistons is stuck causing unequal application.

So inspect the rear brakes. Also after a sustained application of brakes check the temperature of the discs and drums (don’t burn yourself). A disc or drum that is different in temperature from its counterunit raises suspicion of those two.

Hope that helps.

I would suspect a caliper. Not entirely unusual for corrosion or contamination on an older vehicle to form and make the piston stick once it’s pushed back into the bore. If you work on the vehicle yourself you can do this…

Jack up the front of the car. Have someone press the brake pedal and release. As soon as they release, turn the wheel. It should immediately turn without dragging. Do the same thing to the other side. If it drags you found the side that is the issue. If it drags or hangs up, crack the bleed screw and see if it releases. If it releases the dragging brake it is potentially the hose, otherwise it is potentially the caliper.

The above is assuming the rotors were replaced or properly refaced and the hardware was properly installed with the pads.