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Replacing vacuum pump 2014 Sierra

Welder2014

By Welder2014
in Troubleshooting & Recalls

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Welder2014 Enthusiast

Welder2014

Posted
Posted

Going to replace my vacuum pump with the new designed one. Has anyone removed the lower steering shaft to gain more access while doing his repair. Could doing this cause any damage to steering system? Looks like I could just remove the steering shaft knuckle for more clearance.  Thanks.  

tbarn Senior Enthusiast

tbarn

Posted
Posted

No problem. Just keep the steering wheel locked in place. It doesn't matter what  position wheel is, just keep it there.

Fasthotrod Enthusiast

Fasthotrod

Posted
Posted

I had no choice than to disconnect the steering shaft... getting to the bolts on the pump pretty much required it. Looking back, I should have done that first instead of fighting it. 

 

Start your truck and rotate the steering so that the steering shaft bolt is easily accessable, then shut it down and lock the steering in place. Make sure that there isn't a bind between your tire position and steering, because once you take it loose, it's going to move on you. (Ask me how I know this. Oops.)

 

Thankfully, my wife was able to get into the truck and slowly rotate the steering wheel while I aligned it back into place for reassembly. 

 

I also bought the little belt removal tool you'll need for the vacuum pump belt... but it sat a little high and got hung up on the aluminum housing above it. Rotating the crank with a large ratchet was fun... and the belt feel like it was slipping because the stupid belt removal tool wasn't allowing the pulley to continue to rotate. Your mileage may vary... but I hope you don't run into the same issue as I did.

 

On mine, there was a small wiring harness that ran under the pump (not connected to the pump, just ran under it) that required me to disconnect some lock down tabs to free it up. Taking the pump out required me to pull/rotate the pump forward towards the radiator, as the pump pulley was too big to pull it back towards the rear and fit through where the wiring harness was located. 

 

I probably spent more time bitching about the GM Engineer that designed it that way than I did wrenching... definitely something that was designed to be installed on the assembly line easily without much thought towards ease of replacement. (Like a few other things on these trucks.)

 

I found a bit of metal/debris in the lower part of the opening where it bolts to the block. I used a magnet, then my finger, a rag, and some spray to try and get that crap out of there... didn't want it getting back into the engine. 

 

Mark

silveradosid Senior Enthusiast

silveradosid

Posted
Posted

go to the HOW TO SECTION and read sambone 95 write up on how to replace the pump i did mine without removing the steering shaft but i also have every tool known to man the hardest part is trying to use a torque wrench to tighten the bolts. if i had to do it again i would remove the steering shaft

Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted

Any sort of metal shaving is not good.

Hopefully the pumps failure did not release any of that into the oil system.

Have you done a recent oil change to check for shavings there?

Vacuum Pump failure is notorious for causing engine damage as well if it is not caught in time.

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