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Discussion Starter #1
a friend of mine is looking into late 80s and newer diesel 1 ton duallys, problem is we are finding them with 200k miles and above, some close to 300k.
how long will the engines run for and what the average cost of puting in a new engine if we do it ourselves. owning the custom shop the new engine would be done easily, its just a cost thing
 

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Discussion Starter #3
ya its what he can afford
 

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GM first came out with a diesel that was a converted 350. You can find these in some late 70's models. DO NOT BUY ONE. They have serious problems. The motor cannot take the tourque. Im sure its hard finding one these days anyways. They have just about all blew theirselves up.
In the 80s, GM produced the 6.2L diesel. This is a great diesel, but very underpowered. The diesel is naturally asperated (non-turbo), giving it the dragging feel. As far as longivity, this is the diesel to have.
In the mid 90s, GM redesigned the 6.2L to a 6.5L Turbo diesel. The early runs had some problems, but the later runs (1997-up) were pretty reliable. These had much more power than the 6.2L.
Then in 99 started the Duramax which has been changed a few times so far.

In all honesty, I would try to fing a late 80s to early 90s 6.2L. Banks makes a turbo setup for this motor too which gives it a "kick in the pants". If you can find one, a 6.5L diesel in a 1997-1999 truck is a great choice too.

Hope this helps....
 

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HOT AIR BALLOON OWNER
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6.5 turbos can be nice with some mild upgrades to breathe and cooling system updates. Don't expect them to be the greatest, but I bet one worked up would be competitive with a stock 5.9 and easily out do a similar vintage 7.3.

The stock exhaust is fucking terrible (the downpipe made me laff once I saw it). They need injectors around 100k (no big deal, go to Marine 6.5s for +40hp), turbo is small but for 12-15psi it'll do, '94+ got electronic IPs from the mechanical... so you can chip them easy. Do an updated glow plug kit for faster starts and cleaner when cold.

Get a good radiator, later water pump, late dual thermo assy, updated plastic fan with clutch, and you're good. Basically 1997+ specs.

I have seen IC kits, but you add a ton of piping which just adds lag. So that's a judgment call.

I'd love one in a Suburban... they do have 80Es and usually 3.73:1 gearing from what I have seen. Why GM never put the Dmax in the later Suburbans is beyond me.
 

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HOT AIR BALLOON OWNER
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And no, the 350 Diesel wasn't a converted gasser block. Had lots of issues with TTY fasteners, moron techs at dealers, water traps needing to be drained, etc.
 

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Hmmm, from what I read the 350 diesel was a derivitive from the 350 Buick motor.
Anyways, not the best diesel.

Duramax did start in 01, I said 99 earlier....my bad.
 

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HOT AIR BALLOON OWNER
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Close, Olds designed it. Big bore... yes, not something I'd want either. :jester:
 
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