6.6 Duramax Swap?

[Towtruck]

Has anyone done a dimensional check to see if one of these things will fit the space in a J truck? Looks like the accessories and turbo are packaged well for a swap. Anything to watch out for besides the instrument cluster issues? Thanks.

[mark j]

I was wondering the same thing today. Only had a limited time to search but found a post on TheDieselGarage.com listing the 6.6 at 830 lbs with dimensions similar to a BBC. I doubt this includes accesories though. A website about the 6.6 in the 2005 H1 noted that they had to lift the body 2 inches to fit the 6.6 compared to the GM 6.5 turbo diesel it replaced so I'm sure you'd need to do the same. I'm still looking for the actual dimensions though... I'd like to compare the 6.6 to the Cummins 5.9. I think the 3.9 cummins is a good fit- I just have a hard time with the premium these engines command compared to the plentiful 5.9's. I think the 6.6 would have the Cummins 5.9 beat in the weight department by 200 lbs. It probably isn't too realistic as the 6.6 puts out 360 hp and 650 lb/ft of torque- the first time you step on it with a load you'll twist your frame into some pretzel configuration!

[Towtruck]

Just did some more research. Sounds like it's a very big lump. Rumors of a 4.7 V8 in the future, though. Thanks.

[DieselSJ]

I know the guys that swap them into earlier GM chassis have a problem and either have to use a body lift or modify the firewall. They are also a wiring nightmare and the guys have swapped in the later model dashboards because the systems are so tightly integrated.

[The PIG Smith]

I know the guys that swap them into earlier GM chassis have a problem and either have to use a body lift or modify the firewall. They are also a wiring nightmare and the guys have swapped in the later model dashboards because the systems are so tightly integrated.

One of the Moderators at the TheDieselPage, Jim Bigley, wrote a book on swapping Duramax engines into earlier rigs.
Here is my posting about this book:

Duramax Diesel Conversions book (http://www.ifsja.org/forums/vb/showthread.php?t=40483&highlight=Duramax)

One thing I would like to know more about, is that GM reported produced a Duramax crate engine with a stand alone computer.
The few reports about them have been they are very pricey, like $10K+
But the exciting thing is the small detail of the stand alone computer.
This would make wiring this beast manageable.
Maybe a person could get a wreck to use a donor, purchase this stand alone computer from a GM Stealership, then make the swap.

Also, another fact I can not confirm is the Duramax uses the standard Chevy bellhousing bolt pattern.
So, if this is true, then a person could put a high modified TH400 behind one of these things.

IMHO, the Duramax is lighter and has more HP than both the Cummins 6BT and the Ford Powerstroke.
While it would be a challenge with many problems to solve, I do believe this is a doable swap that ordinary folks can perform.

[shimniok]

Dumb question-- why this versus a 6.2L ? One would have to find a turbo bolt on so maybe that's the main reason. But the weight is not much more than an AMC V8... not sure on size...

[DieselSJ]

Brian - the bellhousing pattern is the same.

I know that if my 6.5 ever spits its guts all over the road, a DMax is going to replace it. My 700R4 was built to stand up to one.