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Gorehamj

Huge GM Truck Brake Recall Announced by NHTSA - Is Yours On The List?

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From what I have read it sounds like this recall is primarily for the folks who have a Duramax.  I’ve been wrong before but diesels have used a vacuum pump for many years.

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Welcome to the 21st Century, where most gas engines now have vacuum pumps. First time I saw one was in a '06 VW Passat with a 2.0 gas engine.

Edited by Jsdirt

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So took the truck back Tuesday.   Dealer called a few hours later, said they don't hear any whining noise from the pump and can not replicate the problem.   They said they will go ahead and reprogram the EBCM per the recall anyway.   Service advisor called on speaker with the tech there and we talked through exactly what I was experiencing.   I mentioned I definitely hear the whine in the mornings and at low speed, they asked if they could keep the truck overnight to see how it sounds in the morning.  I said fine.  

 

They called back yesterday afternoon and said they don't hear any noise, the pump still tests fine, they have no indication as to why I get the message on the dash and the hard clicking brake pedal.   They did perform the recall / update.  

 

I go to pick it up, start it up and she's whining away, right there at the dealer, so I go back in and just ask if someone can come out here and listen.   Service advisor brings the tech out and I run the rpm in park to about 1000rpm and there is an unmistakable whine, again to me sounds like when a steering pump is going bad on an old car.  But it's coming from the vacuum pump.   Tech tells me and the service advisor "yeah my 2017 makes the same noise."  So which one is it?   It's normal, or you don't hear it?    I told him my 2016 didn't do it, and this truck didn't do it when it was new. 

 

Tech also starts telling me how the pump is only there to help out when there is not enough engine vacuum present.   I say no, the pump is the only source of vacuum.   He argues with me.   I tell him there is no vacuum line from the booster to the intake, he says yes there is.   I say to him "With all due respect, if you want to show me where that is, I have no problem learning something new" so I pop the hood and he says "Oh, yeah, there is none".   Why do I know more about this truck than the service tech???   

 

He also seemed to have no idea how the ABS system kicks in to assist in braking, and told me the ABS only works if the wheels slip, and if the ABS was kicking in the truck would come to an immediate stop.   And that the ABS system has nothing to with any of this.   Sensing I would not be getting through to him, I thanked him for looking at the truck and we went on our way. 

 

If it acts up again I'll be doing the electric pump and be done with this.    

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48 minutes ago, TwoBallScrewBall said:

So took the truck back Tuesday.   Dealer called a few hours later, said they don't hear any whining noise from the pump and can not replicate the problem.   They said they will go ahead and reprogram the EBCM per the recall anyway.   Service advisor called on speaker with the tech there and we talked through exactly what I was experiencing.   I mentioned I definitely hear the whine in the mornings and at low speed, they asked if they could keep the truck overnight to see how it sounds in the morning.  I said fine.  

 

They called back yesterday afternoon and said they don't hear any noise, the pump still tests fine, they have no indication as to why I get the message on the dash and the hard clicking brake pedal.   They did perform the recall / update.  

 

I go to pick it up, start it up and she's whining away, right there at the dealer, so I go back in and just ask if someone can come out here and listen.   Service advisor brings the tech out and I run the rpm in park to about 1000rpm and there is an unmistakable whine, again to me sounds like when a steering pump is going bad on an old car.  But it's coming from the vacuum pump.   Tech tells me and the service advisor "yeah my 2017 makes the same noise."  So which one is it?   It's normal, or you don't hear it?    I told him my 2016 didn't do it, and this truck didn't do it when it was new. 

 

Tech also starts telling me how the pump is only there to help out when there is not enough engine vacuum present.   I say no, the pump is the only source of vacuum.   He argues with me.   I tell him there is no vacuum line from the booster to the intake, he says yes there is.   I say to him "With all due respect, if you want to show me where that is, I have no problem learning something new" so I pop the hood and he says "Oh, yeah, there is none".   Why do I know more about this truck than the service tech???   

 

He also seemed to have no idea how the ABS system kicks in to assist in braking, and told me the ABS only works if the wheels slip, and if the ABS was kicking in the truck would come to an immediate stop.   And that the ABS system has nothing to with any of this.   Sensing I would not be getting through to him, I thanked him for looking at the truck and we went on our way. 

 

If it acts up again I'll be doing the electric pump and be done with this.    

Unbelievable...but believable with GM

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Great example of why I'm so adamant about NOT going to dealerships for work outside of warranty (and sometimes even for that!). This is what you get for $120/hr with 300% parts markup. A private garage is always cheaper, and if you find the right one, they'll be 100x more capable of fixing your problem ONCE.

 

Sounds exactly like the dealership I dealt with back when my Silverado was new. Same, B/S stories from the employees, just trying to make you, the customer, go away.

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is it possible to make a simple vacuum canister and run a separate line to the manifold to get vac capacity, then when the booster needs vac power you got it. might be worth delteing the DOD v4 system and running standard v8 config, for constant vac supply. truth is the v4 mode has no improvement to fuel mpg in the city and 2 mpg gain on the hwy. better off removing these two parts

Edited by flyingfool
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Same principle as a vacuum canister for cars with huge camshafts back in the day. It would work long enough to keep low brake efforts at traffic lights, I think. GREAT idea there! You might be onto something ...

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I do a ton of highway and am not interested in losing the AFM.   I have pulled 28mpg average over 50 miles on the highway with AFM on, and it stays engaged at surprisingly high speeds (78-80 mph).   Actually seems that sometimes it's in V4 more at 80 than it is at 65, maybe due to a little more torque available at that RPM in 6th.  I did think about running a vacuum canister with two ports with check valves, one to the pump and one to the intake somewhere, so that I would get both pump and intake vacuum accumulated in the canister.   Then a single outlet to the booster.   But I don't want to drill holes in the intake while under warranty and I'm not sure if there's somewhere I could tap it without modifying it.   Also reading about pump failures that take the brake booster down with it, or worse, part of me wants to just lose the noisy belt driven engine-oil-lubricated pump altogether. 

 

Me personally, what I will most likely do like I said is go with an electric vacuum pump and ditch the belt driven pump altogether if it acts up again.    I need to search around to see if anyone makes a bypass pulley for the belt driven pump, or if there is a way to just remove the pump and re-route the belt if I do go with an electric pump.  The whining noise creeping through the quiet campground is embarrassing, quite frankly.  

Edited by TwoBallScrewBall

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I noticed zero fuel mileage difference after installing a Range device that disabled AFM on mine. Mileage  on this thing has been trending downward ever since the day it left the showroom. Was 18 mpg when I first got it. A year later, 16.5 average. Stayed there for a few years, then dropped to 15, then 14, now 13. The truck also runs stronger than it ever has, so this tells me it's adding alot more fuel than it used to. Whether that's multiple injector failures, or pre-programmed by GM to get you to ditch your "old" truck and buy new, we'll probably never know.

 

Never had these sort of issues with carburetors. I got 17.5 MPG on a carbureted '00 4.3 V6 out of a Jimmy, when it got 18 with the buggy, and failure prone FI. Had more electrical problems with that vehicle than any in my entire life - all went away once the FI was gone!

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My 28,000 mile testing on my 14 showed no difference in mileage with it on or off. This was at Hwy speeds of 70 MPH and up. In town it was so annoying between the V-4 and trying to go to high gear. I would put in M5. It perform well there. Eventually I bought a tune and turned it off. There are people on here where speeds are lower, trucks are lighter, who changed their suspension and temperatures. They worked real hard to stay in V-4, that showed mileage improvement. At 60 MPH I did too. As much as 3 MPG without it. A traffic jam forced me on a secondary highway.


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44 minutes ago, TwoBallScrewBall said:

I do a ton of highway and am not interested in losing the AFM.   I have pulled 28mpg average over 50 miles on the highway with AFM on, and it stays engaged at surprisingly high speeds (78-80 mph).   Actually seems that sometimes it's in V4 more at 80 than it is at 65, maybe due to a little more torque available at that RPM in 6th.  I did think about running a vacuum canister with two ports with check valves, one to the pump and one to the intake somewhere, so that I would get both pump and intake vacuum accumulated in the canister.   Then a single outlet to the booster.   But I don't want to drill holes in the intake while under warranty and I'm not sure if there's somewhere I could tap it without modifying it.   Also reading about pump failures that take the brake booster down with it, or worse, part of me wants to just lose the noisy belt driven engine-oil-lubricated pump altogether. 

 

Me personally, what I will most likely do like I said is go with an electric vacuum pump and ditch the belt driven pump altogether if it acts up again.    I need to search around to see if anyone makes a bypass pulley for the belt driven pump, or if there is a way to just remove the pump and re-route the belt if I do go with an electric pump.  The whining noise creeping through the quiet campground is embarrassing, quite frankly.  

try the corvette parts, belt, pully brackets and e-pump

Edited by flyingfool

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On 9/11/2019 at 10:33 AM, NoProblem said:

Well shoot! It doesn't look like they'll foot the bill for new brakes, which at about 64k miles I think I need because they are starting to pulsate when I brake now.

Check out www.maxbrakes.com. I've upgraded two vehicles with them and haven't been disappointed at all!

 

Gamma

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Check out www.maxbrakes.com. I've upgraded two vehicles with them and haven't been disappointed at all!
 
Gamma

The prices are awesome. I might give them a try next job I do.

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They did the update without much fanfare, did not notice much difference afterwards. At any rate, I found a Colorado Trail Boss with a Baby Duramax, and the Green Machine is gone as of today.

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