I think we can all agree the 6.2 is a beast and the latest version is only getting stronger. With that being said the new 5.3 is no slouch with it's 355HP. So just how far behind is it compared to the older 6.2? Has anyone owned both?

 

I wouldn't think they're be a world of a difference . I have only owned 5.3 . I would imagine the 6.2 has more torque and worse gas mileage than the 5.3

 

the new 5.3 vs the old one is night and day. As for the 6.2L I have never owned one. But I imagine the extra 50 hp and 30 ft-lbs would still be pretty noticeable under your right foot.

Problem with the 6.2L is that you have to pick certain options that I wouldn't want, to get that package...not sure if its like that for you guys State side....but GM Canada makes me choose stuff I dont want, or between suff I do, like between a 6.2L and heated and cooled seats.

Sorry, but cold air on my hoop wins over the 6.2L

 

All RCSB bone stock. My 05 2wd 5.3 A4 3.73 ran 9.84. My 07 4x4 5.3 3.42 ran 10.39. My 14 5.3 4x4 A6 ran 9.13.

 

Yep, same thing down here! GM could blow toyota out of the game if it offered the big gun in lower optioned trucks, or how about a RC 2WD !

 

Wow...that a fine running 5.3! I would guess the 1/4 mile equivalent would be low 14's,...nice!

 

Preaching to the choir man.

 

Thank you. I was very surprised!

 

just bc they say you can pull it doesnt mean you should. Kind of like some of the L5P(and other diesel folks) talking about hooking to 30,000lb loads. Yep it may do it, doesn't mean it should be done.

 

The gen 5 5.3 bone stock, on e85 makes similar power to the previous gen 6.2 (per gm's stock numbers)
Interestingly it makes 20 less hp but 1 less tq.

6.2 403/417
I'm not exactly sure what octane those numbers are but GM recommends minimum 91 on those engines. So it should be with 91

Gen 5 5.3 on 87 is 355/383 and e85 is 380/416
So on premium fuel the numbers would be somewhere in between

But as far as how the truck will perform... the newer truck can also be had with an 8 speed that would help close the gap.

I went through this a ton when I got my current truck. I was flip flopping between my current truck and a 2013 denali with a 6.2 and until I saw the OE numbers for the 5.3 on e85 I was leaning toward the 2013 truck. I'm so so so so happy I did not end up with that truck.

May not matter to most people what the e85 numbers are but I have e85 close to home and run e85 at all times. With intake headers exhaust and a tune on e85 this little motor is really impressive.