In this video, we're gonna be doing the top five problems on this third generation GMC
Sierra 3500.
Now, there's nothing wrong with this vehicle, every car has their problems.
These are the top five that we have found with this one.
Number one, knock sensors.
Now, the knock sensors on this vehicle are located right here and there's one on the
opposite side as well.
If you have a knock sensor code, chances are you need to replace the knock sensors.
Now, it's important to keep in mind that these knock sensors are very sensitive.
When you torque these, you wanna torque them to the proper specs.
And then sometimes the wires get messed up, so it's a good idea to get a new wiring harness
or a connector with the wires on it.
Now, some of the older versions of these vehicles had the knock sensors underneath the intake.
So, just before you order them, just double-check to make sure the knock sensors are on the
side just like this one.
Number two, the AC belt tensioner.
Now, you can see it real good from underneath the vehicle.
And it's right here.
All it does is it puts the tension on the belt for the air conditioning compressor.
So, you may notice that you don't have any AC.
And if you don't, check to see if your belt is on there.
In the event that that belt comes off, you're gonna wanna replace the belt and the tensioner
itself.
To replace that, you do have to take the other belt off as well.
And then take these two bolts out.
Pull that out, put the new tensioner on, put the belt back on, put the other belt on as
well.
Number three, bad grounds.
Now, you may notice door locks cycling on their own, lights on your dash flickering,
or even other strange electrical problems.
Now, on the passenger's side of the engine, there's a ground right here.
There's a cable that goes from the battery, from the negative side of the battery, and
then there's another wire right here that goes to the engine wiring harness.
Now, you definitely wanna clean this so you can loosen up that nut, or this is actually
a stud, a stud with a nut.
So, if you take that off, clean that ground.
And then if you notice all this green corrosion, that cable actually needs to be replaced.
So that's not gonna make a good connection.
So if you see any corrosion like that, replace that.
Here's another ground strap that actually has already broke.
As you can see, it's badly corroded.
So, that needs to be replaced.
So, if you see this ground strap in this condition and it's not broken, you're gonna have to
replace it because eventually it's just gonna break.
So, if you take it and it starts to crumble.
It's no good.
And there's another ground right here on the driver's side right at the front of the driver's
door.
And this one can give you some issues as well.
Just because it looks like it's tight and looks good, it doesn't mean it is.
Take that bolt out, clean up the mounting areas a little bit.
You can use some sandpaper or a scuff pad.
Put that back together and that should be good.
Now, those are the common ground issues, but there is other grounds on the vehicle.
Number four, front impact sensors.
The front impact sensor is located right here.
Now, this vehicle only has one, sometimes you'll have two.
And this one is obvious that it's split down the middle.
It's badly corroded.
Now, what that's gonna do is put an airbag light on, and if you scan it and check the
airbag system, you'll have a front impact sensor code.
What you wanna do is disconnect the battery first, then disconnect this connector.
There's a little lock on there, you pull that out, disconnect that, and then take this bolt
out.
Take the new sensor, put the bolt in, torque it properly, put the connector back on and
then reconnect the battery, clear the code, and you should be good to go.
Number five, inner tie rod ends.
Now, you may or may not notice any more slop in the steering wheel.
When you're going down the road, you may have to correct a little bit more.
There could be a little bit of play in the inner tie rod end.
If you put the vehicle up in the air and shake the tire back and forth, you can see that
boot moving in and out.
In that case, it's got to be replaced.
When you go to replace this, what you can do is loosen up this jam nut right here.
And then you can either take this outer tie rod end off by taking the wheel off, taking
that castle nut off on the outside, pulling that down, and rotating the tie rod end off,
or you can take some pliers and just loosen up the tie rod.
Taking that out, it's just gonna take a little while.
And then you can take an adjustable wrench or a larger wrench and just take this part
off here.
And then installing it, it's gonna be the same.
So, those are our top five problems that we found on this GMC.
If you enjoyed this video, make sure you subscribe to our channel, ring that bell, turn on all
notifications so you don't miss any of our videos.