Which dually - 8.1 vs pre-DEF 6.6?

[Frankenchevy]

Man, newer trucks are a pita. I’m half tempted to 12v swap my 1975 f350. It’s a super cab c&c and the rear end/frame look pretty stout to me.

 

[Fastduramax]

This is not even a debate, Dmax period end of any gas motor nonsense for towing... If you're going to tow anything heavier than a moped gassers SUCK anyone who tells you otherwise has never towed with a Dmax, Powerstroke or Cummins... Not to mention the vast tuning options with the Dmax, toss a 120hp non delete tune in it you wont even know that camper is behind you and that's from experience...

 

[Grit dog]

If you’re not doing daily work with it, I’m not certain what you could possibly do with a dump trailer that your 3rd gen wouldn’t handle just fine. Don’t even need a dually unless you have a GN trailer and GN pin weights. Which the 3rd gen will still handle over 4k of pin weight easily.
If you are using it regularly and highway speeds/mountains, the 8.1 makes sense to me other than it’s cheaper than a diesel. Otherwise a LLY or LBZ will walk a 8.1 easily with a trailer. And a small tune and it’ll absolutely destroy the 8.1 but not the Allison.
Idk why the 8.1 is even a consideration unless infrequent use.

 

[Vbb199]

And there is the legendary 8.1/6 speed truck, over 500k on it and continuing to haul junk around

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STANLEY!

 

[bucket]

This is not even a debate, Dmax period end of any gas motor nonsense for towing... If you're going to tow anything heavier than a moped gassers SUCK anyone who tells you otherwise has never towed with a Dmax, Powerstroke or Cummins... Not to mention the vast tuning options with the Dmax, toss a 120hp non delete tune in it you wont even know that camper is behind you and that's from experience...

It's a two way street here. Anyone with this opinion has little to no experience with an 8.1L. And I am someone that has DEFINITELY spend A LOT of time towing heavy loads with a Duramax. An 8.1 is not to be compared with a GM 6.0 or a Ford 6.2 or an Dodge whatever they put in those things.

I'm not at all saying that an 8.1 is superior, but it certainly is comparable and can hold a candle to a Duramax.

 

[mxer147]

Oh, I forgot to elaborate on the finicky Duramax PCM thing. I have no idea how many times I've been pulling a load down the highway and I've lost all power and had to pull off the side of the road, clear random fault codes, then get back along my way. It's always some stupid pidly little insignificant thing that the tuning isn't happy about, so it goes into some kind of limp mode that is basically undriveable. All the trucks too, not just one or two of them.

I’ve experienced limp mode on my 04, no codes but I am fairly certain it was related to filling the tank to the very top. One time died under significant load, other time it was after restarting.

 

[bucket]

I’ve experienced limp mode on my 04, no codes but I am fairly certain it was related to filling the tank to the very top. One time died under significant load, other time it was after restarting.

It's always something completely stupid that sets them off. And usually when it goes into limp mode, it sets a few other codes because evidently the pcm is too stupid to figure out why other sensor readings are out of range (due to high throttle % and high speed, I guess) because it's in limp mode. By far, the most annoying part is the low coolant sensor in the expansion tank. If that tank gets a bit low, it will put you in limp mode even if the truck is running cool as a cucumber. It really sucks if that happens when you're near the top of a mountain pass and have to stop, still hanging half way out in the right lane.

Ever since that incident, I bypass the low coolant sensor on every one that I drive.

 

[77Dmax]

The duramax will have better resale value. Folks are all over the older diesels. The 8.1s are beasts, but will always use way more fuel getting the same job done.