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5.3 vs 2.7

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GMC Guy77 New Member

GMC Guy77

Posted
Posted
23 hours ago, ember1205 said:

 

Nope. This is from the 2024 manual, but same Turbomax engine.

Screenshot 2023-12-06 at 9.14.29 AM.png

Good to know, thanks

  • 2 weeks later...
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Grumpy Bear
Grumpy Bear

1894 the Benz Velo, a 1.045-liter, 63.4 cubic inch motor made 1.5 hp and was the horsepower king of planet earth. By 1928 the Duesenberg straight 8 7 liter (420 CID) Supercharged made 265 hp. 2015 Bug

TrueBlue
TrueBlue

In June I bought an LT with the 2.7. I liked the grunt it put out. But at 700 miles the oil pan started leaking, and it gave me a chance to rectify my "mistake" of not getting the 5.3 to begin with. I

fondupot
fondupot

doubt. 

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Texcl2 Enthusiast

Texcl2

Posted
Posted

I drive a 2.7ho and a 5.3 both 2022’s both now  have just over 30k miles. I personally like the 2.7 better, it feels more responsive. The 5.3 gets 4 to 5 mpg worse mileage. I have had no serious problems with either. The 2.7ho pulls a trailer just as well as a 5.3 and might have a slight edge mpg wise but the lead shrinks here. If the 2.7 makes it to 250k without a major malfunction I will be happy and classify it as better than the 5.3 but that has yet to be seen. 

  • Like 1
Bikerjon Enthusiast

Bikerjon

Posted
Posted
2 hours ago, Texcl2 said:

I drive a 2.7ho and a 5.3 both 2022’s both now  have just over 30k miles. I personally like the 2.7 better, it feels more responsive. The 5.3 gets 4 to 5 mpg worse mileage. I have had no serious problems with either. The 2.7ho pulls a trailer just as well as a 5.3 and might have a slight edge mpg wise but the lead shrinks here. If the 2.7 makes it to 250k without a major malfunction I will be happy and classify it as better than the 5.3 but that has yet to be seen. 

Does your 2.7 use oil?

Diamond817 Enthusiast

Diamond817

Posted
Posted (edited)

The 2.7 might get the jump on the 5.3 to 30mph but the 5.3 will start pulling away and get to 60mph a second faster and will continue to widen the gap into the 1/4 mile. The 5.3 also will perform way better passing at highway speeds, the 2.7 runs out of breath in the higher rpms and at passing at highway speeds. If you're mostly a local city driver, then yeah, the 2.7 works, but if you're a mostly highway guy like me, the 5.3 is the way to go.

Edited by Diamond817
  • 1 month later...
Mshawn Enthusiast

Mshawn

Posted
Posted
On 11/30/2023 at 4:57 AM, Mshawn said:

Work and back is 80+ miles for me and I’m getting 22-23 consistently with my 5.3 and I’m a crew cab z71 5.3 L84 all interstate though.

Update: work and back is up to 26.4 mpg with a 4wd z-71 5.3 what other 1/2 ton v8 4wd can do that?

  • 3 weeks later...
Gangly Senior Enthusiast

Gangly

Posted
Posted

With a lift, AT's, and removed front air dam, my Z71 is  getting around 21 mpg on the freeway doing 75-79 mph.  If I drop the speed down to 70 mph, I'll get 22+ mpg.  Current odometer reading is 120K+

newdude Senior Enthusiast

newdude

Posted
Posted (edited)
On 12/18/2023 at 8:10 PM, Diamond817 said:

The 2.7 might get the jump on the 5.3 to 30mph but the 5.3 will start pulling away and get to 60mph a second faster and will continue to widen the gap into the 1/4 mile. The 5.3 also will perform way better passing at highway speeds, the 2.7 runs out of breath in the higher rpms and at passing at highway speeds. If you're mostly a local city driver, then yeah, the 2.7 works, but if you're a mostly highway guy like me, the 5.3 is the way to go.

 

 

I own a 2.7 HO, came from a 5.3 before it.  Never had a "run out of breath" scenario with the 2.7 HO vs my 5.3.  

Edited by newdude
fondupot Senior Enthusiast

fondupot

Posted
Posted
2 hours ago, Gangly said:

With a lift, AT's, and removed front air dam, my Z71 is  getting around 21 mpg on the freeway doing 75-79 mph.  If I drop the speed down to 70 mph, I'll get 22+ mpg.  Current odometer reading is 120K+


doubt. 

  • Like 2
ember1205 Senior Enthusiast

ember1205

Posted
Posted
1 hour ago, fondupot said:


doubt. 

Actual/Calculated? I also doubt it. 

 

Guesstimated by the crappy algorithm in the truck and displayed in the dash? Maybe.

 

My last truck consistently showed at least 1MPG higher than actual. 

  • Like 1
  • 2 weeks later...
Diamond817 Enthusiast

Diamond817

Posted
Posted
On 2/7/2024 at 12:05 PM, newdude said:

 

 

I own a 2.7 HO, came from a 5.3 before it.  Never had a "run out of breath" scenario with the 2.7 HO vs my 5.3.  

Punch it when traveling at 75-80mph, let me know what happens. The 5.3 takes off like a rocket, the 2.7 falls flat on its face. I test drove both extensively before buying. Again, if you're a city/local driver the 2.7 works, but that's where it ends.

  • Like 1
fondupot Senior Enthusiast

fondupot

Posted
Posted
1 hour ago, Diamond817 said:

Punch it when traveling at 75-80mph, let me know what happens. The 5.3 takes off like a rocket, the 2.7 falls flat on its face. I test drove both extensively before buying. Again, if you're a city/local driver the 2.7 works, but that's where it ends.


I agree with this. I’ve driven both. My 2.7 feels fine around town. Torquey and peppy. But on the highway the passing power really lacks compared to what a 5.3 has. 
 

The 2.7 is fine for cruising at highway speeds tho. Just not good for passing power. 

  • Like 1
TrueBlue Enthusiast

TrueBlue

Posted
Posted
22 minutes ago, fondupot said:


I agree with this. I’ve driven both. My 2.7 feels fine around town. Torquey and peppy. But on the highway the passing power really lacks compared to what a 5.3 has. 
 

The 2.7 is fine for cruising at highway speeds tho. Just not good for passing power. 

 

Good example of the difference between torque and horsepower.

MaverickZ71 Senior Enthusiast

MaverickZ71

Posted
Posted (edited)

Real world fuel mileage with the hammer down, like you apparently like to drive, is not appreciably different between the 2.7, 5.3, and 6.2. There are decisions to make in life. If you want fuel mileage in a GMC, the 3.0 diesel is for you. Trucks are not pony cars,but If you want the sense of acceleration, it's the 6.2 with active exhaust. Or stay with Stellantis and look at the Hurricane SST HO for the '25 Ram 1500; 500 hp and 600 ft lb. 

 

https://youtu.be/ji4OD31rBaI?si=Wx-TWYx0ma3KlLef

 

https://youtu.be/jSVg06mGiWI?si=MS8KRTkjUkw5UT-a

Edited by MaverickZ71
Vincej138 Enthusiast

Vincej138

Posted
Posted
On 2/16/2024 at 3:44 PM, Diamond817 said:

Punch it when traveling at 75-80mph, let me know what happens. The 5.3 takes off like a rocket, the 2.7 falls flat on its face. I test drove both extensively before buying. Again, if you're a city/local driver the 2.7 works, but that's where it ends.

 

Maybe for the pre-refresh.. My 22' with the HO version takes off at 70-75 when passing other trucks. That's with 35's. Def does not fall flat on its face whatsoever, and thats when pulling a decent grade in heading up north from Phoenix. So maybe flat the V8 can pull it. But ill take the extra torque when it matters. 

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