Questions about GMC Sierra's

[MrGiggles]

The 5.3 we have now is hardly comparable to the 99-07 5.3s that earned their reputation. Those didn't have any of the cylinder deactivation or VCT stuff that they do now.

A lot of the problems were limited to the 07-13 generation. GM made many improvements, the biggest being that instead of shutting off the same 4 cylinders in eco mode, they will now shut off 2 or 4 differing cylinders, and periodically switch between varying combinations to equalize conditions in the engine. Most of the problems were lifter failure and oil consumption in the cylinders that deactivated.

To reduce pumping losses, the valves need to remain closed on the dead cylinders, so the lifters essentially need to collapse on demand. It's a new concept and GM didn't quite get it right the first time. 

I have an 06 with 330k. Original engine (has had a rear main and oil pump seals, probably several water pumps), on its second trans and rear diff. I want to see if it'll go to 500k. It burns some oil and needs a transfer case.

[snagged in outlet 3]

I had 99 Yukon the old model.   230k miles.   Engine and transmission fine.  Knickknack electronic stuff started wearing out.   Got rid of it when the rear doors wouldn’t lock.   Slept in it many nights while fishing.  Air mattress and space heater in the winter.  

[fishinwrench]

My '04 Tahoe has some electrical weirdness going on, all seems related to the body control module.  Probably a dirty ground connection or a bad pin in a connector somewhere.....but I have checked and cleaned all of them that I can find.

Door open ding-ding-dinger is very faint (can just barely hear it) sometimes,  and it has repeatedly blown the front blower motor resistor 3 times in 2 years. I've gotten to where I can swap that 60.00 POS out in about 4 minutes flat. 🙂

I upgraded wheels & tires and had a Rough Country 3"lift kit and suspension installed.  Ever since the lift kit it has had a rattle somewhere in the rear that I can't isolate.  Only hear it on bumpy washboard roads.  Sounds like something loose inside the back door.   And I can't get the stupid tire pressure monitors to pair with it's controller.....so I get a constant Tire Pressure Monitor not communicating code.   I run 10 ply BFG/AT's though.....so having a flat just AIN'T GONNA HAPPEN.  😉

[aarchdale@coresleep.com]

20 minutes ago, fishinwrench said:

My '04 Tahoe has some electrical weirdness going on, all seems related to the body control module.  Probably a dirty ground connection or a bad pin in a connector somewhere.....but I have checked and cleaned all of them that I can find.

Door open ding-ding-dinger is very faint (can just barely hear it) sometimes,  and it has repeatedly blown the front blower motor resistor 3 times in 2 years. I've gotten to where I can swap that 60.00 POS out in about 4 minutes flat. 🙂

I upgraded wheels & tires and had a Rough Country 3"lift kit and suspension installed.  Ever since the lift kit it has had a rattle somewhere in the rear that I can't isolate.  Only hear it on bumpy washboard roads.  Sounds like something loose inside the back door.   And I can't get the stupid tire pressure monitors to pair with it's controller.....so I get a constant Tire Pressure Monitor not communicating code.   I run 10 ply BFG/AT's though.....so having a flat just AIN'T GONNA HAPPEN.  😉

I got so tired of my tire sensors with new wheels, i just put them in a pressurized pvc pipe with a shrader valve and threw it in the back, almost a year now and the lights have stayed off

[MrGiggles]

8 hours ago, fishinwrench said:

 it has repeatedly blown the front blower motor resistor 3 times in 2 years. I've gotten to where I can swap that 60.00 POS out in about 4 minutes flat. 🙂

Usually the blower motor is to blame. Worn and drawing too much amperage, or it has a candy wrapper or something wadded up in the fan.

[snagged in outlet 3]

I’m with @fishinwrenchin that I wish they made option free versions of trucks.   All the options are great until they don’t work.  Even a door lock actuator can make an older vehicle too expensive to fix.  

[gotmuddy]

16 hours ago, Basfis said:

The fuel management quote is bunk unless you can share one credible source with defect rates. 
 

zero issues with 5.3’s for me and at least 1 million  miles combined. Current 2018 is approaching 80k without a hiccup. None of my trucks have had any warranty work or repairs performed. Maybe I’m lucky. 

Unfortunately I cannot post proprietary company information on a public message board.  What I can tell you is that I work for one of the biggest warranty companies in the country, and that the 2007 and up 5.3 gm engine with AFM has a much higher rate of failure than pre-07 engines.  I can also tell you that chevy has a huge problem after 15 years still.  You should consider yourself lucky, or maybe you change your oil more often than chevy recommends. 

[gotmuddy]

11 hours ago, MrGiggles said:

The 5.3 we have now is hardly comparable to the 99-07 5.3s that earned their reputation. Those didn't have any of the cylinder deactivation or VCT stuff that they do now.

A lot of the problems were limited to the 07-13 generation. GM made many improvements, the biggest being that instead of shutting off the same 4 cylinders in eco mode, they will now shut off 2 or 4 differing cylinders, and periodically switch between varying combinations to equalize conditions in the engine. Most of the problems were lifter failure and oil consumption in the cylinders that deactivated.

To reduce pumping losses, the valves need to remain closed on the dead cylinders, so the lifters essentially need to collapse on demand. It's a new concept and GM didn't quite get it right the first time. 

I have an 06 with 330k. Original engine (has had a rear main and oil pump seals, probably several water pumps), on its second trans and rear diff. I want to see if it'll go to 500k. It burns some oil and needs a transfer case.

I wish.  They may be better now but the labor is considerably higher now(30 plus, compared to 19.3)

[196champ]

I have a 2016 Sierra 2500 Duramax, knock on wood i have had next to no issues and owned it since new.

It now has 160,000 miles.

My uncle purchased a 2020 Sierra 1500 as a retirement gift to himself, at 13,000 it exploded due to the issues stated above.  He now runs around in a 2021 F150.

[MrGiggles]

1 hour ago, gotmuddy said:

I wish.  They may be better now but the labor is considerably higher now(30 plus, compared to 19.3)

You seem to know a lot about them, what do you do?

Is that time for for engine replacement or lifters?