New 8.3L GMC Engine
- Thread starter M and E
- Start date
RoadJunkie
Well-known member
Can't say much for the timing; Bigger engines have traditionally meant more fuel usage.
Gas for sure, diesel not as much. Larger displacement, same or even more torque produced, engine revs slower to produce the same energy. Smaller displacement, same torque as the larger displacement engine, the engine revs faster and relies on boost and EGR to make the same output....less fuel efficient. Plus, it will benefit form the new emissions standards. They'll add taller gears too, for sure. My bet, GM/GMC will be the class leader in torque and fuel efficiency.
RoadJunkie
Well-known member
Regardless, I would wait a year or two before considering a purchase.
I'm with you on this one. A lot of these engines we get today are used in other countries before they come here. In those cases, I'm not as leery. That's not the case with this engine, as far as I can tell, and this is its first rodeo.
I'm only keeping this truck (26 GMC) for four or five years. ALl three should all have their ground-up rebuilds live, tested, and refined by then.
Midnight Rider
Prominent Member
It sounds nice. But the old Duramax is a beast. No need to change any time soon.
Agree completely, at least technically. But for me, I'm definitely going to buy one of the big three's next gen trucks in four or five years. Can't help myself!
Midnight Rider
Prominent Member
Me to.
Me neither 😂😂
I plan to a truck in the near future However I have the opposite approach of you guys. I prefer to have the last generation of the known platform versus the early generations of the new platform. I guess for me that means I need to focus on getting a 2026 sooner than later.
I may be moving sooner rather than later. I’ll wait to see the redesigns but this is really good stuff. Rumor is that GM will now have SuperCruise (not in the article below) on HD trucks while towing. That is a game changer. Could you imagine the reduction in fatigue with that option? They have it on their other trucks with electronic steering. The numbers are strong.
www.roadandtrack.com
GM’s Huge 8.3-Liter ‘Mongoose’ Diesel for Chevy and GMC’s HD Trucks Cranks Out 1230 LB-FT of Torque
Plus, electric power steering and brake-by-wire join the GM HD party for the first time.
www.roadandtrack.com
I'm OK with Super Cruise What I'm not OK with is being an early adopter to the new engine platform.I may be moving sooner rather than later. I’ll wait to see the redesigns but this is really good stuff. Rumor is that GM will now have SuperCruise (not in the article below) on HD trucks while towing. That is a game changer. Could you imagine the reduction in fatigue with that option? They have it on their other trucks with electronic steering. The numbers are strong.
GM’s Huge 8.3-Liter ‘Mongoose’ Diesel for Chevy and GMC’s HD Trucks Cranks Out 1230 LB-FT of Torque
Plus, electric power steering and brake-by-wire join the GM HD party for the first time.
I'm afraid I'll be cut if I'm too close to the cutting edge of technology.
I've learned I don't need to be the first.
As a matter of fact I prefer to be the last of the old existing, well known and sorted out platform versus being the first of the cutting edge, unknown Unproven, unsorted out platform.
I’m with you on this engine. But the super cruise is almost “old “ now. I’m sure I’m going to wait until all of the big 3 launch their new HDs. We’re actually really happy with the GMC so far…no need to make a move now. But, I can’t wait to see what drops!I'm OK with Super Cruise What I'm not OK with is being an early adopter to the new engine platform.
I'm afraid I'll be cut if I'm too close to the cutting edge of technology.
I've learned I don't need to be the first.
As a matter of fact I prefer to be the last of the old existing, well known and sorted out platform versus being the first of the cutting edge, unknown Unproven, unsorted out platform.
Flyer32RLS
Well-known member
Noone has mentioned it and I didn't take the time to read the above articles.
CHatGPT says the new GMC has 555 HP and 1230 Torgue.
My 2026 6.7L HO (very reliable engine, tried and true) has 500HP and 1200 torque.
I honestly have never needed 500HP and 1200 of torque but it sure pulls my 32RLS super!
Like others, steer away from new. The 6.7L has reliant as it is did go thru many growing pains but tweaked into an awesome engine.
And getting 11.5MPG when towing is super!!
Anyone else praying the diesel prices come down soon??? WalMart dropped to $5.74 this morning!
Sorry California, stop closing your refining plants!!
CHatGPT says the new GMC has 555 HP and 1230 Torgue.
My 2026 6.7L HO (very reliable engine, tried and true) has 500HP and 1200 torque.
I honestly have never needed 500HP and 1200 of torque but it sure pulls my 32RLS super!
Like others, steer away from new. The 6.7L has reliant as it is did go thru many growing pains but tweaked into an awesome engine.
And getting 11.5MPG when towing is super!!
Anyone else praying the diesel prices come down soon??? WalMart dropped to $5.74 this morning!
Sorry California, stop closing your refining plants!!
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Fishfnatic
Well-known member
We had some 8 and 10 percent grades for several miles coming out of West Virginia into Virginia. Auto diesel brake is the bomb for grades,