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6.6 Gasser Longevity

MORSNO

By MORSNO
in 6.6L Gas V8 (L8T)

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Pryme Senior Enthusiast

Pryme

Posted
Posted
13 hours ago, Shatterz said:

68k miles here and no problem issues. Have a 3500 L8T at work as well with 128k that’s gone through 2 6L90s but the engine is solid. 
 

My guess on what’s the first thing to go on these that is irrespective of maintenance or usage, the high pressure fuel pump for direct injection. About 2100 PSI cam driven and it’s only a matter of time until they go very similar to a diesel’s high pressure pump in design. Located on the very back of the engine nearest the firewall and under the intake manifold it will be a joy to one day replace 😄. 

I read a tech say it only takes 30min to get to it. I don’t know how accurate that is though. 

 

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Another JR
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I use my 2021 to reduce the amount of air swirling around in my barn.   

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carkhz316 Enthusiast

carkhz316

Posted
Posted
On 1/1/2026 at 11:23 AM, Pryme said:

I read a tech say it only takes 30min to get to it. I don’t know how accurate that is though. 

 

If you're mechanically inclined, you can certainly get to it in a half hour or so. The Gen 5 engines are very similar to previous LS-based v8s for intake manifold removal.

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  • 3 weeks later...
UltimateToolReviews Enthusiast

UltimateToolReviews

Posted
Posted
On 1/1/2026 at 12:23 PM, Pryme said:

I read a tech say it only takes 30min to get to it. I don’t know how accurate that is though. 

 

I don't think you could do it in 30min, but my mechanic friends say it's about a 2 hour job, just awkward but not hard. Normally runs around $1000-1200 for a shop to do it. 

Pryme Senior Enthusiast

Pryme

Posted
Posted
17 hours ago, UltimateToolReviews said:

I don't think you could do it in 30min, but my mechanic friends say it's about a 2 hour job, just awkward but not hard. Normally runs around $1000-1200 for a shop to do it. 

Yeah, 30mn to get to it but I suppose completing the whole job might take closer to two hours. I don’t know what the actual book time is in the job but good techs always beat book time. 

  • 4 weeks later...
James Beyer Enthusiast

James Beyer

Posted
Posted

Running good so far on 2024 2500hd with 81,000 miles

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