You accidentally put power steering fluid in the master cylinder of a 2005 Dodge Durango and brakes are now mushy do you have to bleed brake lines get it out?

Yes, you absolutely must flush and bleed the brake lines. Power steering fluid is incompatible with brake fluid and will severely compromise the brake system's ability to function properly. The mushy pedal is a clear indication of this. The power steering fluid has likely contaminated the brake fluid and damaged seals within the master cylinder and possibly the calipers.

Here's what you need to do:

1. Do not drive the vehicle. Driving with contaminated brake fluid is extremely dangerous.

2. Obtain the correct brake fluid for your 2005 Dodge Durango. Check your owner's manual to be certain of the correct type (DOT 3, DOT 4, etc.).

3. Completely flush the brake system. This is best done by a professional mechanic using a pressure bleeder. This ensures all contaminated fluid is removed from the lines, calipers, and master cylinder. Attempting to do this yourself might not be fully effective.

4. Inspect the master cylinder. Power steering fluid can damage the seals in the master cylinder. It may need to be replaced.

5. Bleed the brakes. After flushing, the brake lines must be bled to remove any air introduced during the process. Again, professional help is recommended as improper bleeding can lead to air in the lines, resulting in spongy brakes or brake failure.

Because you've introduced a foreign substance into a critical safety system, it's strongly advised to take your Durango to a qualified mechanic immediately. The cost of repair is far less than the potential cost of an accident caused by brake failure.