Here come the Mongoose (8.3L Duramax)

nmp1 · 2026-09-25T11:57:01-0500

5150 · 2026-09-25T12:21:11-0500

As expected the pearl clutching over GM releasing this new engine is laughable with all the typical ignorant and just plain made up statements. "OMG, GM had to come out with new engine to compete with Ford". You mean the 10 years newer Ford diesel that it took them that long to come up with to be able to compete with the Duramax? And then they had to make it a hot V so it wouldn’t look like a complete clone of the Duramax. Having owned both during the same time period I can say 03-05 they were close performance wise with GM being more reliable but from 06-11 Ford 's diesel and transmission program wasn't even in the same ballpark as GM. Not until Ford dropped the 6.7 and 6R140 were they comparable.
Anyone who can read a graph can see this 8.3's initial release numbers are at maybe 50% of its reliable power potential. This thing is already making 1200lb-ft at a high idle. When the 6.6 Duramax came out it was rated at 300hp. Today it’s rated at 470hp.. Ten years later Ford dropped the 6.7 with 390hp and it's rated at 500hp today. Gee, ya think maybe GM left a little on the table with this new engine? No idea wtf they were thinking with "Mongoose" though. What a stupid name.

John889 · 2026-09-25T12:23:19-0500

The biggest turnoff with the Silverado is that it's made by General Motors, and god forbid something is wrong with the engine they will just hide, ignore and stall till the next generation of engines.

Cool HP/Trq output though

AZsurveyor · 2026-09-25T12:25:56-0500

5150 said:
As expected the pearl clutching over GM releasing this new engine is laughable with all the typical ignorant and just plain made up statements. "OMG, GM had to come out with new engine to compete with Ford". You mean the 10 years newer Ford diesel that it took them that long to come up with to be able to compete with the Duramax? Having owned both during the same time period I can say 03-05 they were close performance wise with GM being more reliable but from 06-11 Ford 's diesel and transmission program wasn't even in the same ballpark as GM. Not until Ford dropped the 6.7 and 6R140 were they comparable.
Anyone who can read a graph can see this 8.3's initial release numbers are at maybe 50% of its reliable power potential. This thing is already making 1200lb-ft at a high idle. When the 6.6 Duramax came out it was rated at 300hp. Today it’s rated at 470hp.. Ten years later Ford dropped the 6.7 with 390hp and it's rated at 500hp today. Gee, ya think maybe GM left a little on the table with this new engine? No idea wtf they were thinking with "Mongoose" though. What a stupid name.

There has been no greater display of ignorance in this thread than this post that seeks to accuse others of being ignorant.

Apparition · 2026-09-25T12:33:34-0500

5150 said:
As expected the pearl clutching over GM releasing this new engine is laughable with all the typical ignorant and just plain made up statements. "OMG, GM had to come out with new engine to compete with Ford". You mean the 10 years newer Ford diesel that it took them that long to come up with to be able to compete with the Duramax? Having owned both during the same time period I can say 03-05 they were close performance wise with GM being more reliable but from 06-11 Ford 's diesel and transmission program wasn't even in the same ballpark as GM. Not until Ford dropped the 6.7 and 6R140 were they comparable.

It almost aligns with Ford deciding to stop using Navistar and make their own. Weird.

5150 · 2026-09-25T13:16:27-0500

AZsurveyor said:
There has been no greater display of ignorance in this thread than this post that seeks to accuse others of being ignorant.

Ford Karen.

Ragin Cajun · 2026-09-25T13:35:43-0500

AZsurveyor · 2026-09-25T14:08:06-0500

5150 said:
Ford Karen.

As if this couldn't get more ironic - a current Ford owner who became noticeably agitated after factual statements were made regarding GM and their manufacturing quality.

majorbison · 2026-09-25T16:20:52-0500

having to go to 8.3 liters to make what a 6.7 does reliably is embarassing

5150 · 2026-09-25T18:51:58-0500

AZsurveyor said:
Have you seen the 6.6L? Just to replace the notoriously bad injectors, it feels like you need to dismantle the entire truck plus your last six vehicles.

These guys must be used to this routine. For an oil change, they pull off all four tires and lift the entire vehicle, not just the cab, because these things sit so low to the ground. I swear my Civic has more clearance than a standard 2500 GM. For whatever it's worth, my Civic has bigger tires than what these HD built like rock trucks do from the factory!

AZsurveyor said:
As if this couldn't get more ironic - a current Ford owner who became noticeably agitated after factual statements were made regarding GM and their manufacturing quality.

From the clown claiming that to change the oil on a GM HD you need to pull the tires and lift the truck and that his Civic has more ground clearance and bigger tires. Yup you've got all the credibility and objectivity to be talking about anything.

5150 · 2026-09-25T18:56:48-0500

NightForceFan · 2026-09-25T19:18:58-0500

5150 said:
From the clown claiming that to change the oil on a GM HD you need to pull the tires and lift the truck and that his Civic has more ground clearance and bigger tires. Yup you've got all the credibility and objectivity to be talking about anything.