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Showing results for tags 'booster'.
I found the brake pedal in my GMC Sierra 6.2 model 2014 is hard at idle after 2 to 3 presses. I cancelled the original vacuum pump line and connected the brake booster to the intake manifold vacuum source. The old line was covered with air filter element to avoid dirts to enter the vacuum pump. Now the problem is completely resolved. Is there any other options? Anyone tried this idea and appreciate if can share his experience and feedback. Regards,
Hi All, In my GMC truck 1500 Sierra, it makes an abnormal noise under the brake pedal area while pressing it. The sound comes directly from interior and its like a whistle sound and called sometime a hissing noise. The brake system functions properly and without any defects except the mentioned noise. Is it possible from the brake booster? or could be from other sources? Appreciate sharing your experience feedback in this problem. Regards, Abdulla brake gmc.xspf
I've got a good looking, good running, booster leaking, 94 Silverado heavy duty K2500 with brake option code JB7. It's a 4x4, has 13 x 2 1/2 eight lug drums, 8600 GVW, 5.7. All the things that make it a JB7. ( Plus the sticker in the glove box.) I bought it in 2007. I ordered a booster from a local auto parts store using the JB7 code & discovered ( the hard way ) that the pushrod hole was too small to fit the brake pedal stud. Went to a different store that had some boosters in stock & found that option JB6 had a larger hole & would fit the pedal. With some misgivings, I bought & installed that one. It's defective. The outer case halves seperate slightly when the pedal is pressed so the master cylinder & brake lines move forward about 1/8th inch. The brakes work but it makes brake action really touchy & brake release slightly delayed. The truck's drivable, so before getting another booster, I'd sure appreciate hearing from anyone that's replaced this booster & if you had any problems with the job & with parts. Also, I'm looking for the best way to get the dang pushrod retainer clip off of the brakepedal stud. It took about three hours last time...
Got an interesting one for the forum. After the truck (2016 GMC Sierra) has been sitting a while (usually over night or for a few hours) the pedal let's out a nice squeak. On rare occasions I can get it to do it twice in a row, but most of the time the squeak is only for the first press then is gone for all the other presses. Normal daily driving I don't hear it, it's only the first press or when I have to hit my brakes hard (ex, cut off by someone). My local dealer service department (who's treated me well and has good mechanics) looked at it and said they can't repeat it enough to truly diagnose it. Some squeaks are real quick and others last about 2 seconds. The only way I can describe it is like a relief valve letting some air out, but with a squeak. Sometimes I can hold the pedal in place after depressing and the squeak continues to let out. It's not like a metal plunger rubbing on a rubber boot as I depress the pedal, plus I would be able to make the sound every time if that were the case. Below is a video I took on two different occasions, they are looped a couple times. You'll hear what I'm talking about and see that it's gone on the second press. I did have the vacuum pump replaced due to the recall about a year ago, I noticed it after that but the dealership said the pump and vacuum is holding well the entire time, even when it squeaks. They only guess they had was to replace the brake pedal assembly or the brake booster, but admittedly said that would just be throwing parts at it. Just got the truck back today, didn't get charged for the diagnosis since they couldn't figure it out. Now I'm turning to the forum. Any idea what's going on?!?