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Vacuum pump & mechanics

Adam Leinss
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300 Blackout
300 Blackout

That depends if oil was found in your vacuum line. If it was then the recommendation is to replace the additional parts of the braking system. If no oil was found in the line and they don’t suspect oi

newdude
newdude

AFM is why. It allowed them to change the AFM so it runs more with low/no load. When you drop 4 cylinders, you drop your vacuum supply. Helps for added brake assist to increase pedal feel over the

montytx
montytx

This happened to me today. Ordering a new pump. I can tell you this, you have to push down really hard to bring these to a stop. I assume they included them in the engine because they drop to 4 cyl.

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Chris j New Member

Chris j

Posted
Posted

I took it to the local dealer and they said that the pump was 240 and I would also have to replace the booster which was another hundred and thirty and then also the master cylinder according to the service bulletin I got on parts.com and found the vacuum pump for a $110 i tested booster and it operating normal dealer also said vacuum pump was on back order for 3 mths...but this is not a common problem....yea right...so yes 43000 dollars on truck i purchased brand new  ill be doing it myself last month my ac compressor went out that was $1500 and has been in and out of shop since i bought it...never again will i buy a gm product sad thing is on 50,034 miles on truck

 

  • 3 weeks later...
Consumer Advocates New Member

Consumer Advocates

Posted
Posted
On 1/11/2018 at 8:52 PM, Chris j said:

I took it to the local dealer and they said that the pump was 240 and I would also have to replace the booster which was another hundred and thirty and then also the master cylinder according to the service bulletin I got on parts.com and found the vacuum pump for a $110 i tested booster and it operating normal dealer also said vacuum pump was on back order for 3 mths...but this is not a common problem....yea right...so yes 43000 dollars on truck i purchased brand new  ill be doing it myself last month my ac compressor went out that was $1500 and has been in and out of shop since i bought it...never again will i buy a gm product sad thing is on 50,034 miles on truck

 

Still under warranty? Did GM refuse to pay for the vacuum pump repair?

  • 4 months later...
Jamax99 New Member

Jamax99

Posted
Posted

Gmc 2014  1500.  89,000 miles I was driving yesterday doing 55 and lost total brakes , I put foot pedal all way down , it was has if I had no brakes . I was able to roll to side of highway. Had to get a tow to local mechanic . Found that vacuum pump belt was broken and that pump was bad.   Replaced with parts from dealer at cost of $900. .  Let me say I will be selling my truck, my 17 year old drives it , sometimes and I have to say it was one of worse moments ever driving. I'm 46. . If my son was behind wheel he would have crashed.  I am so mad! I called dealer and they told me I was out of warranty.  My problem is belt and pump go out and you loose brakes?  This is crazy. . 

  • 1 month later...
Deal New Member

Deal

Posted
Posted

Add me to the list. Happened to me yesterday on expressway. Only warning was that it happened earlier yesterday morning at idle and went away. What a shock. Montytx, I agree with you completely about safety. There is a law suit. Same thing happened to a lady, I believe in TX, and she couldn't stop and hit another car. This is a big problem and it appears GM knows all about it, but I don't see any recall. I found this info using google search. There is also a GM TB on the fix, which some claim is a misleading repair to dodge the real issue.

CB15LTZ New Member

CB15LTZ

Posted
Posted

Happened to me, as well. Was on vacation and lost brakes as I pulled into a hotel parking lot. A local mechanic diagnosed a bad brake booster. Had that replaced and installed a new booster line. That helped me finish vacation and make it home. Once I made it home, I took it to a Chevrolet dealer. Got the news that I have a bad vacuum pump. I’ll be out about $900 total, assuming I don’t have to replace something else. 

  • 1 month later...
rgoldberg Enthusiast

rgoldberg

Posted
Posted

This happened to my 2016 1500 yesterday. I was coming out of the dealer's mech shop after a full alignment as they were finishing up some accident repair (another driver more occupied with their cell phone than with cars on the road), and on the test drive the vacuum pump failed at 38K miles... I had the Power steering box fail at 16K... Color me not impressed.

KARNUT Senior Enthusiast

KARNUT

Posted
Posted

Vacuum pump, nice little additional part thanks to cylinder deactivation. Cross fingers no metal in your engine. Hummm, that money could have went towards gas.


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Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted
3 hours ago, rgoldberg said:

This happened to my 2016 1500 yesterday. I was coming out of the dealer's mech shop after a full alignment as they were finishing up some accident repair (another driver more occupied with their cell phone than with cars on the road), and on the test drive the vacuum pump failed at 38K miles... I had the Power steering box fail at 16K... Color me not impressed.

Is your truck stock height or lifted/leveled?

2016LTCC Enthusiast

2016LTCC

Posted
Posted

I’d like to know if the 2019 model still uses the mechanical pump. Or if they went with electrical

Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted
2 minutes ago, 2016LTCC said:

I’d like to know if the 2019 model still uses the mechanical pump. Or if they went with electrical

Mechanical pump is GONE for 2019 :thumbs:

rgoldberg Enthusiast

rgoldberg

Posted
Posted
2 hours ago, Sierra Dan said:

Is your truck stock height or lifted/leveled?

Stock height and as a correction the post should say "it was coming out of the body shop" not " I was". It was being driven by a Chevy Tech or Mech to verify proper functionality after the collision repairs

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