CK5
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One Piece at a Time: My 1985 Diesel Suburban

The truck is home and safe. Now, the work begins.

knock-downs are just opportunities for bounce-backs
I’m a bouncy dude.

I have a 599 block you can start fresh with
A thick wall one piece rear main 6.2 would be pretty slick. Thank you for that offer.

Would you have to redesign 99% of the engine compartment, probably.
For sure. It’s a practical certainty. I’d just cut out the engine cross tube and start over. Time consuming, but not that tough.

have a government rebuilt 6.2 still in the aluminum shipping container. I
Appreciate the offer, and your insight.

I’m betting though there’s a part of you that wants to take on the packaging challenge to stuffing a dirtymax under the hood. There’s another part that wants to get the truck back on the road fairly quickly.
I do love to fabricate, but a few wrenches and some time will get me back on the trail for the spring.

I’ve got some calls to make.

David
 
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While i know you have tons of resources for experts, don't forget Russell on here. He's done 2 dmax swaps (~94 and ~2002), and is a MASTER of the computer programming side of the swap.

My dmax suburban was built by someone else, but Russell is the only reason it's still on the road.
@Russell
 
John Leguizamo Christmas Movies GIF by filmeditor
 
I'm really excited about a Duramax, and now I know why you snickered in Moab when it was brought up. I will be watching as it will be my next platform in my truck when it transitions to the next phase of life.
 
Bro.
Get some white Oakleys and flip flops, and cummins swap it. Make sure you squat it too.
I feel triggered.

Ick. I think an 8.1 gasser has a better chance than Cummins. But Dave has an attachment to Detroit mills with a turbski making it’s own atmosphere.
An 8.1 Larry special could be cool, but I like my boat anchors loaded up with the spoolies.

I'm really excited about a Duramax, and now I know why you snickered in Moab when it was brought up. I will be watching as it will be my next platform in my truck when it transitions to the next phase of life.
As long as it's a rowdy bag of hammers, I'm interested.

David
 
I feel triggered.


An 8.1 Larry special could be cool, but I like my boat anchors loaded up with the spoolies.


As long as it's a rowdy bag of hammers, I'm interested.

David
You know I like to party....


The next phase will be body work, paint, cleaned up and no longer abused.
 
An 8.1 Larry special could be cool, but I like my boat anchors loaded up with the spoolies.
David

Nothing says you can’t put a turbski or two on an 8.1.

I’ve taken a ride in a Yukon XL with a Raylar supercharged 8.1 that was pretty fun too.

Though I had an RV customer in Red Deer Alberta that managed to stuff twins on a 8.1 powered class a motor home. I don’t think he had a very good tuner though. Couldn’t keep from melting pistons down. Got slightly bitchy when I laughed at the idea of covering the engine under warranty.
 
12 or so years ago there was a guy in Arizona on here that built up the ultimate 6.2L with all the beef parts and a turbo. Ended up going another route and sold it to another member on here. Have to find that thread…

MaxPF’s build:
 
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I just ordered a new 6.5 Optimizer. It will be here in about three weeks.

This is not the right time to start a Duramax swap. That's a planned project, and I'm not going to confuse it with what would become an opportunistic repair during a very busy year of deliverables for the business. In more detail, the engine cage and rear subframe are tailored to the dimensions of the 6.2/4L80E/Magnum-205, and it's all pretty tight. I'm 100% disinterested in remaking the bulk of that tube work. Fresh Detroit power makes this a bolt in affair, and gets me back on the trail delivering on commitments in a relatively short period of time.

Now, the newest version of the 6.5 has significant upgrades that make it very desirable all on its own. At a high level, they built a block and head and crank that will run 350hp/650lb-ft all day. That's plenty for my purposes. The no-longer-in-production P400 has taken that further (incidentally, I did find a couple of them still available, but I'm not spending that amount of coin for anything other than an LBZ swap). In more detail, the engine I ordered has an improved metallurgical cocktail, webbing and wall thicknesses are increased, heads have a handful of cooling and durability upgrades, it's got all the nice oil spray stuff, and has the same large diamond prechambers that I ran in my 6.2. Turns out. GEP opted to stop using old cast cranks alongside the P400 forged ones, and just settled on the forged piece all around, so these later style Optimizers enjoy that forged bottom end. Pretty nice little upgrade, and all my fuel injection stuff will swap right over. It's almost like GEP now makes the engine that Detroit originally designed over 40 years ago (and GM would go on and cheapen to suit its own needs).

When it gets here, my dad and I will blow it apart, balance the crank, rods, pistons, and flexplate, install a gapless compression ring, stud the heads and mains, install my timing gear set from the 6.2 (assuming it survived), install some other baubles and bolt ons, and get it all back in place. New oil coolers, flushed hoses and lines, turbo health check, clean out the intercooler, and all that prep gets underway, soon. Our friend, @Greg Ducato, agreed to look over the 4L80E while it's out as a good "sniff test."

I'll probably even run back over a few engine cage welds that were really hard to get to, and do a bit of frame reinforcement while I have access. I mean, I might as well. Maybe I spent too long at @Greg72's last weekend.

Time to get to work.

David
 
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Larry and I had a buddy at GEP when we were at Workhorse. They really fixed all the problems gm created when the bean counters caused when they went cheap on the design. He had a pretty wicked gmt400 suburban with a supercharged 6.5 that was pretty killer. He’s the guy that taught both of us how to correctly time the injection pump on 6.5’s with a sonic tool. Ended up fixing 3 post office step vans my dealer in Omaha that go wildly out of time by not following instructions.

That’s a good upgrade and should get you back on the road sooner than a complete swap to a new platform.
 
Where did you order the engine from?
Rubber Duck 4x4. I called GEP to ask with which of their distributors do they enjoy the best relationship.

He’s the guy that taught both of us how to correctly time the injection pump on 6.5’s with a sonic tool.
So neat! That's a fine art. I time with a luminosity probe, and there's still quite a bit of "test and check" to it.

David
 
I just ordered a new 6.5 Optimizer. It will be here in about three weeks.

This is not the right time to start a Duramax swap. That's a planned project, and I'm not going to confuse it with what would become an opportunistic repair during a very busy year of deliverables for the business. In more detail, the engine cage and rear subframe are tailored to the dimensions of the 6.2/4L80E/Magnum-205, and it's all pretty tight. I'm 100% disinterested in remaking the bulk of that tube work. Fresh Detroit power makes this a bolt in affair, and gets me back on the trail delivering on commitments in a relatively short period of time.

Now, the newest version of the 6.5 has significant upgrades that make it very desirable all on its own. At a high level, they built a block and head and crank that will run 350hp/650lb-ft all day. That's plenty for my purposes. The no-longer-in-production P400 has taken that further (incidentally, I did find a couple of them still available, but I'm not spending that amount of coin for anything other than an LBZ swap). In more detail, the engine I ordered has an improved metallurgical cocktail, webbing and wall thicknesses are increased, heads have a handful of cooling and durability upgrades, it's got all the nice oil spray stuff, and has the same large diamond prechambers that I ran in my 6.2. Turns out. GEP opted to stop using old cast cranks alongside the P400 forged ones, and just settled on the forged piece all around, so these later style Optimizers enjoy that forged bottom end. Pretty nice little upgrade, and all my fuel injection stuff will swap right over. It's almost like GEP now makes the engine that Detroit originally designed over 40 years ago (and GM would go on and cheapen to suit its own needs).

When it gets here, my dad and I will blow it apart, balance the crank, rods, pistons, and flexplate, install a gapless compression ring, stud the heads and mains, install my timing gear set from the 6.2 (assuming it survived), install some other baubles and bolt ons, and get it all back in place. New oil coolers, flushed hoses and lines, turbo health check, clean out the intercooler, and all that prep gets underway, soon. Our friend, @Greg Ducato, agreed to look over the 4L80E while it's out as a good "sniff test."

I'll probably even run back over a few engine cage welds that were really hard to get to, and do a bit of frame reinforcement while I have access. I mean, I might as well. Maybe I spent too long at @Greg72's last weekend.

Time to get to work.

David
Sounds like a solid plan. Any idea what the power difference will be?
 
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