I've searched this entire site for pictures of the brake booster rod that people with spongy brakes are adjusting and I couldn't find any. I did this adjustment today (1/2 turn counterclockwise) on my 2004 fx4 and its pretty amazing. I took some pictures to show what the rod actually looks like. I'm not saying people should or should not make this adjustment, but if you do this is what it looks like.

The last picture is brake fluid from my master cylinder after 60,000 miles. Does anyone know if this is normal? The fluid was dark dark green.

 

Hope you changed the brake fluid out! It should be normal a light tan/amber color like new oil.

 

I know you didn't put that fluid back in there ..

Great Pics!! I've read about this being done in the 97-03 models and it having made a world of difference in braking power.. That's on my list..

 

I am assuming the 1/2 turn counter clockwise tightens the brakes up?

 

Correct. There is a gauge you can buy that you put flush against the mc that measures the piston bore depth. You then flip the gauge around and put it flush against the booster. There should then be no gap between the rod and the part of the gauge that measured the bore depth. If there is a gap, the rod needs to be lengthened (turned counterclockwise).

 

Not necessarily - NEW fluid is light tan/amber in color as you say. As this fluid is used some of the additives can darken due to the heat cycling. Also, if the manufacturer used any copper fittings in the brake system, the copper can turn the brake fluid dark (and slightly green). This does not mean that the fluid is "bad". There is a high chance that the fluid is perfectly fine.

When to change brake fluid
- if you race your truck (more high-energy stops could boil the fluid)
- if you tow a lot (same boiling concerns)
- if you feel a soft brake pedal

If your pedal feels fine, it is unnecessary to change the fluid just because it is darker than when it was new.

This is based on technical information, I am a master cylinder engineer. I have done brake fluid analysis for our customers.


BTW - there are large inherent risks with adjusting your booster rod. You could find yourself sitting still by the side of the road with your brakes locked up, and/or cause your brakes to drag. I would advise against it (I will not do it on my truck). You can read more about the risks in my posts in the original posting on adjusting the booster rod.