[88lance]

Hello everyone, bought a GMC Sierra for the first time, it will be my work truck.
It's a 2011 crew cab 4x4, 5.3 with 180k miles.

I have couple of questions that y'all may be able to help me with:

-back door speakers don't work.
I did some research and most of the time it seems like this revolves around the Bose sound systems. Mine doesn't have this though. There's another post where someone simply changed out the door speakers and it started working. Before I start taking my panels off I wanted to check if there's anything else that commonly causes this that I should check with, or if this is actually the problem most of the time. I was just surprised that two speakers would randomly completely quit working all together. No funny sounds or anything, just dead. (Already tried fade)

-should I override my V8-V4 system?

There was some online discussion about when this first came out it was causing problems with excessive oil consumption. When it switched to V4 it was burning the oil or something like that, so there was a lot of plug-in devices that popped up online that you would simply plug into your port that would tell the truck to stay in V8 mode, solving the oil consumption issue. In 2011 was this still an issue? Or is this pretty well resolved by my year of truck? I have been watching it, and it seems like it rarely goes to V4 anyway. I can tell when it does though because the truck makes a low rumble noise and the truck slightly vibrates. Not sure whether to mess with that or not.

-Why does my Bluetooth regularly forget about the phone?

I set up my phone's Bluetooth and it seemed like half the time that I get in the truck and start it, it connects when I start the truck, and the other half the time I get in my truck and start it, it doesn't know the phone is there until I tell it to connect. If I started the truck and walked away from it I could see where it would disconnect and I would have to manually reconnect it, but that's not the case. Is there a reason it does this, or a way to fix this?

Thanks everyone, feel free to throw in any other advice or tips to know about these.
So far I am enjoying it 👍. About to get a leveling kit and some decent tires for it.

 

[Jstucker1976]

Looks in pretty good shape congrats

 

[AlabamaChevy]

I’m not sure about the speakers my 2012 gmc didn’t have a problem with the phone iPhone at the time.
Yes on the v8 get a tuner or better yet dod/afm delete kit.

Time to start modding it up.

 

[MotorEng91]

Welcome to the forum

I would check the door jamb wiring and make sure there are no obvious shorts but with both doors having the same issue seems unlikely. Could be pinched wires behind the stereo if someone replaced the radio before then put the stock radio back in quickly before trading it in.

I would personally turn off the AFM. It does not help fuel mileage enough to justify the potential reliability concerns from what I hear.

There was a TSB for updated valve cover to help oil consumption that ended in 2011 but depends on build date. See link https://static.nhtsa.gov/odi/tsbs/2012/SB-10062524-7690.pdf

Only other thing I would recommend is to change out all the fluids when you can. Then of course enjoy the truck!

 

[MacQ]

Can't help with your questions, but you do have a nice-looking ride there!

 

[Mayor Mags]

I just got my Range AFM disabler this week, and wonder why I waited 2 years to do so. I have a 2008 Silverado with only 51,000...I loathe the AFM feature. I found it would take 2 seconds for the computer to figure out what my foot wanted it to do. I noticed the difference from the Range plug in immediately. No more shuddering and stuttering when taking slow turns onto streets, or when I need to make a move on the highway. It seems so much smoother overall, and whether my mpg gets better or worse is the least of my concerns. It's a V8 truck, and now it acts like one.

 

[88lance]

Thanks for the responses. Will definitely address the V8-V4 issue then. I usually run tuners on my Ford 5.0's, which get traded in at 100K, but since this has almost 200k (and planning on keeping it for as long as it will go), I am hesitant to throw a performance tune at it. Maybe just a light tune and the AFM delete? Or maybe AFM delete only? Who do ya'll suggest for the tuners or deletes for the 5.3's?

That's a good point about both speakers being out at the same time, I will start at the deck and see if I can find anything wrong with the wiring behind it.

Thanks again for the responses, the truck is in great shape except for a bumped in spot right in front of the passenger side tail light on the bed, but the body shop will be correcting that next week. 😁 Tires and level will be coming shortly.

After watching my parents run a few 5.3 Tahoes and Suburbans up to 350K miles before each trade-in, I knew I needed one. haha

 

[shakenfake]

A full delete requires mechanical changes to be made. The failure can still happen with just a tune.

 

[spaddman]

Welcome to the SS forum.

 

[Mayor Mags]

Thanks for the responses. Will definitely address the V8-V4 issue then. I usually run tuners on my Ford 5.0's, which get traded in at 100K, but since this has almost 200k (and planning on keeping it for as long as it will go), I am hesitant to throw a performance tune at it. Maybe just a light tune and the AFM delete? Or maybe AFM delete only? Who do ya'll suggest for the tuners or deletes for the 5.3's?

That's a good point about both speakers being out at the same time, I will start at the deck and see if I can find anything wrong with the wiring behind it.

Thanks again for the responses, the truck is in great shape except for a bumped in spot right in front of the passenger side tail light on the bed, but the body shop will be correcting that next week. 😁 Tires and level will be coming shortly.

After watching my parents run a few 5.3 Tahoes and Suburbans up to 350K miles before each trade-in, I knew I needed one. haha

I'd definitely love a late 90s square body Tahoe with the 5.7 in it. Now those motors were bulletproof. I'm on my second 5.3 with AFM, and it will be my last. No mechanical issues yet, but I swear it's not if, but when with these motors. My truck was just way too good to be true when I found it, so I had to get it.

 

[jamesmross24]

I have a 2008 silverado 5.3l and love it. I've owned it for 10yrs now.

Check over the whole truck for wiring issues. The loom that chevy used sucks.... or at least on my truck it does. Areas that see heat are really bad. I have re-loomed most of the wiring on mine. And the grounds too, haha. Clean all of them.

The DOD or AFM or 4cyl mode..... whatever you want to call it, I'm not a fan of. I got rid of it. You can easily tune out the feature, but I feel, it doesn't help much. If your willing to do some work to the truck, it's well worth it. My truck had nasty lifter noise when it was cold out around 80,000 miles.

 

[jamesmross24]

Also keep an eye on the cab vents. One rain storm did a number on my interior. Had to strip most of interior out after that one. They are cheap and easy to replace.

 

[buckwild27]

The connection at the speakers could be corroded up. I had that problem in mine. Had to replace all the connections to the speakers.

 

[Gimme a Jimmy]

Congrats on your purchase. I recently moved up from an '02 to my 2011 in black.....my first black vehicle! Anyway, I also have a rear speaker not working but the former owner cobbed in an amplifier and another speaker was not sounding clear. I pulled the radio and discovered one of the speakers had the pos/neg connection wrong so that woke up the one speaker. As said, seems you need to look at what wiring you can before pulling the panel and check the speaker itself. Let us know if you get the intermittent "auxiliary" port text on your radio......there is a fix.

I also elected to purchase a Range AFM bypass and am glad I did. I found a mechanic I think I can trust and he says it's a help as well. It's not just about oil consumption but also about lifter failures. I would also suggest a catch can to keep the sludge from going back through your intake. It's amazing the crap it catches.

My stock radio also fails at times to "see" my phone......not often but sometimes yes. Not sure there IS a cure.

Nice looking truck.....enjoy!!

 

[88lance]

Thanks for the responses again. I never knew about the cab vents, maybe that's what happened to all the carpet. It is all stained tan and brown colors. I just didn't care because I have plastic floor covers throughout, but I will definitely check that in case it is letting things in and making it worse.

I'll check for that AFM delete, especially hearing that AFM also affects lifters. I seen so many of these 5.3's go over 400k miles, so anything to help it get there is money well spent. Including the catch can, good idea.

That gives me something to do today, check behind the radio deck and go over all the wire looms to look for exposed areas. 👍. Tonight I'll see if I can order some things for the catch can and AFM

 

[88lance]

Well I'm glad the wire loom was mentioned, in the process of retaping several pieces of that now. Also trying to find a strange noise with the steering, it lets a faint fart noise when turning back to center. Haha.
Does anyone know what this rubber hose is? It's capped on the end and has wires taped to it.

 

[Leveled17yeti]

Congrats the tune or range will make it a lot less likely also plan on changing oil everyb3 to 5 k don’t go by oil life monitor planning on doing a delete of the dod soon but have scored mine lifters perfectly fine for now also amen on catchcan

 

[jamesmross24]

When my cab vents let water in.... i caught it pretty quick. Had to pull all seats and carpet and the foam under. Had to steam clean both a few times to get rid of the smell of mold. Definitely replace them if needed. Can do it from underneath between the bed and cab. They used to be $75 a piece from chevy.

I can't find that connector on my truck. The only rubber hose I have in that area is for the windshield wiper fluid. But it's not routed like that at all. Stays close to the fender. And Definitely stay on top of the wiring. I feel like a lot of gmt900s have issues because of the loom falling apart and bad stuff happens. Then people give up on them once the electrical issues start.

 

[88lance]

Got a lot of the loom wrapped this evening, I'll have to get more tomorrow. The truck did have a wierd smell, and the vents definitely may be to blame. I'll be checking that out tomorrow. 👍 Are the only vents the ones at the bottom back of the cab?
I wonder if the hose is the vent for the fuel? Not sure why it would have wires on it though. I'll try to track it tomorrow.

While I was wrapping wires this evening, I crawled underneath to find oil all over the bottom of the engine. They specifically told me it has no leaks, and was cleanly washed when I went to pick it up. Ugh. So now back to Arlington this week to try to get the dealership to fix whatever it is. I hope they take care of it.
I did notice this has 2 battery trays, not sure if all these do, or if this is something added, but I may take advantage of it for a power inverter sometime 😁

 

[jamesmross24]

That's not a fuel vent.

I'm pretty sure all gmt900s have a second battery tray. Mine does and every truck I've seen does. A common oil leak from under the truck is just above the oil filter. It's a feed and return for an oil cooler. All half tons have it capped I think???? Pretty sure all HDs use it????