Engine on AT4

[Teegunn]

I had a 2020 AT4 with the 3.0 Duramax. Loved the truck and engine, but "service emissions system" error codes kept popping up, putting my truck in permanent limp mode. A month at the dealer, they never could get it fixed so I traded it for a 2023 AT4X with the 6.2. Love the 6.2 so far, but it is thirsty. Same out of pocket cost for fuel since gas is cheaper than diesel, but way less range on the measley 24 gallon tank. This 6.2 needs at least a 28 gallon tank. 30 or larger would be ideal.

I rarely step into it with the 6.2 as I am trying to avg 15 MPG with the truck. But when I do step into it, it really moves. The 3.0 engine was no dog, in fact was very nice to drive. Quick, snappy with the torque and the transmission mated to that 3.0 diesel engine was super nice. But it had to go since unfixable problems (which it seems lots of these service emission system problems are happening with the 3.0 engine) made it undriveable. Love my AT4X though.

 

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[Madox44]

I have a '20 with the 5.3, and it moves. we have a fleet of 6.2 hds at work (just fleet vehicles, not in at4 trim) and they are definitely not quick, though they have plenty of torque. Thirsty is not the word; I've never even seen 13 in one (I'm getting 20 in my at4). for a guy who doesn't tow alot and puts alot of miles in, I couldn't be happier. unfortunately I don't believe they offer the 5.3 anymore

 

[sloopdawg]

just ordered mine,
so give it to me, tell me why my thinking does not compute
got the 6.2 (because i'm old school)
10 speed trans w/ electronic precision shift
got the tow package that give me the 373 diff

not planning on doing much towing but...
my thinking is, i'll be cruising around town mostly
with the lower gear diff, the truck will move somewhat smoother
and pull a little better when towing
if i was planning on long hauls i would want the 323 diff for mpg
anyway it's a done deal now
i'll let you guys how i like it

 

[Cablebandit]

It may take off a little quicker with the 3.73 gear but that's about it. Once in motion the ten speed pretty much negates the rear end ratio these days. So with the 3.23 you'll get bout the same towing and probably a little better fuel economy. Of course mine is a diesel so what do I know!?

 

[Yeldawb]

just ordered mine,
so give it to me, tell me why my thinking does not compute
got the 6.2 (because i'm old school)
10 speed trans w/ electronic precision shift
got the tow package that give me the 373 diff

not planning on doing much towing but...
my thinking is, i'll be cruising around town mostly
with the lower gear diff, the truck will move somewhat smoother
and pull a little better when towing
if i was planning on long hauls i would want the 323 diff for mpg
anyway it's a done deal now
i'll let you guys how i like it

Hey Sloopdawg- When do you get your truck? I’m supposed to pick mine up this Saturday….I have about the same setup as you I believe.

 

[sloopdawg]

still waiting, hopefully not far behind you
i want to see yours when you start taking pics

 

[Yeldawb]

I picked it up yesterday… I’ll take more photos soon!