5.3 Engine on GM

355HP Z71 · December 18, 2016

I have a 2014 RCSB Z71 with the 5.3 and I have no complaints . Plenty of power and decent gas mileage .

jerryh20 · December 24, 2016

~~it would nice if the dealer would deactivate tmc if owner requested it. this is my first 5.3 and some problems noted by other owners concerns me.~~

Cowpie · December 24, 2016

5.3 is a great engine

6.2 is an incredible engine

Well, the jury is still out on the 6.2L Eco. It really hasn't been out long enough to prove any long term reliability and durability. It is not really a setup that attracts serious commercial users and such that can really put it thru it's paces in harsh environments and see if it can hold up over the long term. The 5.3 Eco is just a 5.3 Vortec with direct injection. And the 5.3 Vortec does have a good track record when taken care of properly. And the premium required thing about the 6.2 really shoots it in the foot on how attractive it is to many buyers. I guess "incredible" is purely subjective.

Arth · December 24, 2016

You might be incorrect in your comparison of the new 5.3 to the old.

From what I have read posted around here the newer engine shares something like two bolts with the older.

I think this new 5.3 is fine but the jury is still out for both engines due to direct injection and carbon build up in my book.

Well, the jury is still out on the 6.2L Eco. It really hasn't been out long enough to prove any long term reliability and durability. It is not really a setup that attracts serious commercial users and such that can really put it thru it's paces in harsh environments and see if it can hold up over the long term. The 5.3 Eco is just a 5.3 Vortec with direct injection. And the 5.3 Vortec does have a good track record when taken care of properly. And the premium required thing about the 6.2 really shoots it in the foot on how attractive it is to many buyers. I guess "incredible" is purely subjective.

Cowpie · December 25, 2016

And you could be right. Both are too new to make much of a case for long term reliability. The 5.3 Eco has seen a lot more use in commercial fleet applications and doesn't seem to be a problem. That is the only edge in comparing both engines.

HondaHawkGT · December 25, 2016

The 5.3 eco is closer to the 6.2 eco than it is the 5.3 vortec. Haven't seen as many complaints on oil consumption as the previous 5.3 so that's an improvement. Premium isn't required in the 6.2, just highly highly recommended as power and fuel economy is affected by lower octane fuel, especially under high load.

New2GMC · December 25, 2016

I have the 5.3 in my 2014 gmc 1500 and next week I'll have the 5.3 in my new 2016 gmc 1500

New2GMC · December 25, 2016

Where does the misconception on the gas mileage come from? 2016 Denali 1500 6.2 8spd 25mpg "Come On Man"

I never got this good of mileage on my 2014 5.3 6spd!

Do you find 58 mph avg gets you the best mpg?

Cowpie · December 26, 2016

The 5.3 eco is closer to the 6.2 eco than it is the 5.3 vortec. Haven't seen as many complaints on oil consumption as the previous 5.3 so that's an improvement. Premium isn't required in the 6.2, just highly highly recommended as power and fuel economy is affected by lower octane fuel, especially under high load.

And then the point of buying the 6.2 to have it derate by using regular as opposed to just buying a 5.3 that can use anything from regular to E85, would be what?

HondaHawkGT · December 26, 2016

And then the point of buying the 6.2 to have it derate by using regular as opposed to just buying a 5.3 that can use anything from regular to E85, would be what?

Don't get me wrong, I'm not trying to recommend running 87 octane on a regular basis with a 6.2, BUT depending on where you live or end up while on a road trip, 91 isn't always a widely available option.

Truthfully I wouldn't even recommend 87 for the 5.3. Plenty of independent third party tuners have noted that the 5.3, even in stock form, doesn't run well on 87 (most engines made in the last 10 years don't run well on that piss haha).

truckguy82 · December 26, 2016

Well, the jury is still out on the 6.2L Eco. It really hasn't been out long enough to prove any long term reliability and durability. It is not really a setup that attracts serious commercial users and such that can really put it thru it's paces in harsh environments and see if it can hold up over the long term. The 5.3 Eco is just a 5.3 Vortec with direct injection. And the 5.3 Vortec does have a good track record when taken care of properly. And the premium required thing about the 6.2 really shoots it in the foot on how attractive it is to many buyers. I guess "incredible" is purely subjective.

Yeah basically a "I have no idea what I'm talking about" post

Cowpie · December 26, 2016

All it takes a several reads thru varied posts on different forums to find out the the both the 5.3 Eco and the 6.2 Eco have their fair share of issues. Maybe oil consumption compared to the early AFM 5.3 Vortecs has improved, but I have seen more threads about 6.2's having some major issues over the 5.3's. Some even grenading early on. About the only engine in the GM stable nowadays that could be considered trial worthy of being considered a long term reliable engine is the 6.0L Vortec. That one has a very good record of tacking up over 300,000 miles with limited engine issues. They are just about bullet proof engines.

And if anyone is truly honest, the 6.2 only has a niche market in the 1500's. Again, many folks are not going to use premium as a primary fuel choice. And those that truly need some serious towing ability will side step it and move on to the 2500 with the 6.0L or the Dmax. Towing is a lot more than what shows up on a dyno. And given the stock 2500 6.0L comes with 4.10 ratios, significantly better brakes, and a payload and towing capacity that even the best 1500 can only dream of, the 6.2L is more about a muscle car type of scenario or bragging rights, and hence, a niche market.

Commercial buyers, again, primarily sidestep the 6.2 for the same reasons. There are many 5.3's that are used in pickup fleets that show good results long term. 6.2's hardly rate a blip on the radar when it comes to commercial fleet pickup buyers. I see and deal with many operations that use a lot of pickups, and I haven't seen a commercial fleet 1500 pickup yet with a 6.2L.

So when it comes right down to it, the 6.2 has no significant track record that can even remotely be considered proven and reliable. My contention is more than reasoned and sound.

truckguy82 · December 26, 2016

All it takes a several reads thru varied posts on different forums to find out the the both the 5.3 Eco and the 6.2 Eco have their fair share of issues. Maybe oil consumption compared to the early AFM 5.3 Vortecs has improved, but I have seen more threads about 6.2's having some major issues over the 5.3's. Some even grenading early on. About the only engine in the GM stable nowadays that could be considered trial worthy of being considered a long term reliable engine is the 6.0L Vortec. That one has a very good record of tacking up over 300,000 miles with limited engine issues. They are just about bullet proof engines.

And if anyone is truly honest, the 6.2 only has a niche market in the 1500's. Again, many folks are not going to use premium as a primary fuel choice. And those that truly need some serious towing ability will side step it and move on to the 2500 with the 6.0L or the Dmax. Towing is a lot more than what shows up on a dyno. And given the stock 2500 6.0L comes with 4.10 ratios, significantly better brakes, and a payload and towing capacity that even the best 1500 can only dream of, the 6.2L is more about a muscle car type of scenario or bragging rights, and hence, a niche market.

Commercial buyers, again, primarily sidestep the 6.2 for the same reasons. There are many 5.3's that are used in pickup fleets that show good results long term. 6.2's hardly rate a blip on the radar when it comes to commercial fleet pickup buyers. I see and deal with many operations that use a lot of pickups, and I haven't seen a commercial fleet 1500 pickup yet with a 6.2L.

So when it comes right down to it, the 6.2 has no significant track record that can even remotely be considered proven and reliable. My contention is more than reasoned and sound.

-You have not seen more threads of the 6.2 grenading, because I've seen them all, you just made that up.

-you said earlier the 5.3 was close in relation the the vortec 5.3, this completely proves that you are just making your facts up because the gen V motors are completely clean sheet designs

-yes we've all previously established its the motor to get if you want to have a little more fun and serves little practical purpose

-that's great that 5.3's see fleet usage, you are clearly not aware the 6.2 sees duty in the c7 corvette and the camaro ss. It gets the crap beat out of it in forced induction and racing applications. This may be a niche for a 1500 pickup, but GM decided it was going to go into camaro's, corvettes, escalades, and denali's, aka the flagship vehicles and the face of the company.

-the 6.2 and 5.3 are incredibly similar in function and design, the 6.2 could almost be considered the same engine but with additional parts to make it stronger and reliable. Unlike the 5.3, it's got a forged crank and rods.

-if that wasn't enough, the 6.2 gets the same gas mileage

Donstar · December 26, 2016

-You have not seen more threads of the 6.2 grenading, because I've seen them all, you just made that up.

-you said earlier the 5.3 was close in relation the the vortec 5.3, this completely proves that you are just making your facts up because the gen V motors are completely clean sheet designs

-yes we've all previously established its the motor to get if you want to have a little more fun and serves little practical purpose

-that's great that 5.3's see fleet usage, you are clearly not aware the 6.2 sees duty in the c7 corvette and the camaro ss. It gets the crap beat out of it in forced induction and racing applications. This may be a niche for a 1500 pickup, but GM decided it was going to go into camaro's, corvettes, escalades, and denali's, aka the flagship vehicles and the face of the company.

-the 6.2 and 5.3 are incredibly similar in function and design, the 6.2 could almost be considered the same engine but with additional parts to make it stronger and reliable. Unlike the 5.3, it's got a forged crank and rods.

-if that wasn't enough, the 6.2 gets the same gas mileage

It would be a disappointment to see this thread turn sour. Accusing others of making things up with their own unsupported opinions only leads to an argument turning others away.

truckguy82 · December 26, 2016

It would be a disappointment to see this thread turn sour. Accusing others of making things up with their own unsupported opinions only leads to an argument turning others away.

He said the l83 is closely related to the vortec 5.3, that's completely untrue, it's widely known, and will not hesitate to call someone a liar if they present bad information on a public forum as a fact. Even worse is when they know enough to appear knowlegable on the subject. This forum is not just a means of socializing, it's a database of information that people will look at for help.