Brake pedal feel low

[29tomt]

Last year the master cylinder was replaced by a shop and a power flush run. More recently the brake pedal has felt low. The pedal cluster is all the way up. I took it to a brake shop and they pulled wheels, miked the rotors, looked at everything and said they could not find anything wrong. Two years ago I installed new front pads. Rear is way it was 5 years ago when I bought the truck. It has a solid pedal. Have not had to add fluid.


I might add that when getting oil change just prior to going to brake shop, I asked Tire Kingdom to check brakes. They came back with $1200 worth of repairs for hydroboost. Well, I have a traditional vacuum booster, power steering pump and a vacuum assist motor booster whatever. Did I miss anything. My son says irregardless to replace rear pads. Is it possible the rear calipers are froze up putting it all on the front and making pedal low? 2003 Tahoe with 200K on the clock. Otherwise, runs perfect and burns no oil.

I can deal with it but the wife drives a newer GMC that weighs less and stops on a dime and she tends more to run up on cars before starting to brake so not wanting her to drive my Tahoe.

 

[OR VietVet]

May have slight fluid seepage at the back of Master cylinder or at calipers or at lines. Did not say anything about lines when the other shop looked. Could have caliper problems as well. Takes a good eye to get in there and see the caliper operation. Caliper slides could be hanging up and allowing too much caliper piston travel before the pads hits rotors, especially in the rust belt. Had to add any fluid over time?


We recommend that you put all your rig(s) info in your signature so we all don’t have to guess at year, make, model, engine size, trans, rear axle locker…….etc. While you may have posted pertinent info in your first post, you may forget to do it again and the info is needed by us anyway. Makes it way easier on all members that attempt to help, to have that info right up front. It is also recommended that you take a pic of your RPO codes, on the inside cover of the glove box, and post that image in your signature. All this info will greatly help those that will try to help with a problem.


If there is any other info, like upgrades, mods or recent mechanical/maintenance work done, that would be helpful in any post as well. Too many times a question is asked by the poster and after about 10 responses we find out that the poster has done recent work to attempt to fix the problem or work that was done that SEEMS not related to the problem.

 

[PNWYukon]

With 200K on it you should rebuild the calipers anyway. New pads and new rotors all around. Brakes are too important! If in the rustland get Permatex Caliper grease too and lube all the pad guides and moving surfaces.

Check all hard line connections for signs of leaks.

 

[29tomt]

Thanks.