Square Body 350TBI/TH400(2wd) to 6.5/NV4500 (4wd). Advice/Help needed.
 

I have a 1988 GMC R3500 Crew Cab Long Bed (2wd.) I purchased a 78 1 ton 4x4 Crew Cab for the Dana 60 and 4x4 parts. I will be converting my 88 to 4x4 shortbed with the Dana 60 front.

I found an excellent deal on a 94 running 6.5 Turbo Diesel/NV4500 Combo. The guy bought it because it had a brand new injection pump so he did rob that which I will need to find a replacement for. I plan to go look at it on Friday. He said if I buy the combo he will let me get anything I need off the truck since I told him my plans.

So I will need to be converting from 350TBI/Th400 to the diesel combo. Can I pull the entire engine wiring for the TBI, tanks and fuel lines and sell it, or is that a bad idea?

I am not sure what I will need to go about wiring just yet but I am no stranger. I have done a LS swap.

I just can't find an abundance of info like the LS swap because every one has done that.

So some info I need is:
Wiring? Do I need to get anything from 6.2?
Transfer case? Only spare I have is a 78 205 from behind a th350.
Cross member?
Fuel tank/Lines? k5 rear tank or just 2-16gal saddle tanks?
Intercooler
Turbo routing/interference with AC box and what not.
General info.

I am not trying to build anything super fast, I just want the reliability and economy of the diesel plus the pulling power. This truck will just be putting around in the country or pulling something.

I believe the 6.2 and 6.5 are very similar and I know 6.2's came in square so I assumed this shouldn't be too difficult.

So, anyone done something like this? Any threads you can link to or anything would be great!

Re: Square Body 350TBI/TH400(2wd) to 6.5/NV4500 (4wd). Advice/Help needed.
 

I picked up a 1996 F code 6.5 TD last Friday. It was out of a 1 ton dump truck. I got the entire engine, wiring harness, computer, gas pedal, radiator and so on.

I am excited to get started on it for sure. I have a build thread elsewhere but I am still looking for swap threads or information.

Re: Square Body 350TBI/TH400(2wd) to 6.5/NV4500 (4wd). Advice/Help needed.
 

Still curious about any info anyone may have. Considering swapping to a DB2 mechanical pump.

Re: Square Body 350TBI/TH400(2wd) to 6.5/NV4500 (4wd). Advice/Help needed.
 

go with the DB2. what you will want to do is swap to an older harness. if you use the DB2 you will only need to supply 12V to the shut down solenoid in run/start, which carburetor equipped trucks did for the distributor. I recommend manual glow plug controls, since the gm controls can be problematic without an ECM. you will need a solenoid to handle the amperage of the glow plugs. starter and alternator wiring will be similar to carb equipped trucks. you will need to hook up the reverse light switch on the transmission, and a clutch safety switch in place of the neutral safety switch. where you'll run into needing aftermarket support I'd getting the cable driven speedo to work off the nv4500.

get the radiator out of a square diesel and use the engine oil cooler out of the 94, just upgrade the cooler hoses. if you want to use the factory gm turbo setup off the GMT400 (92-99) you will have to modify your evaporator box, but it is doable.

if you grab the harness and the little white module under the ecm out of the donor, you can make a 91 gauge cluster work for the speedo, but you'll have to do some harness connector surgery.

you're going to have to find a late square to rob the hydraulic clutch set up out of.

you're best bet with tanks is to swap to diesel tanks.

Re: Square Body 350TBI/TH400(2wd) to 6.5/NV4500 (4wd). Advice/Help needed.
 

I am on the fence about the DB2 swap.. I have all the wiring and everything to stay with the DS4 and possible just the pmd is dead. I did grab the module and ecm :). I also have the radiator from the donor, it is huge!! Also have the oil cooler as well.

I got a set of hydraulic pedals. I have a build thread going on now, Lets build a 1 ton 4x4 is what it is called, please check it out! I just got the NV4500 mounted in and the test fitting the 6.5 in the frame now.

Do you know if the 6.5 has different engine mounts (the pieces that bolt to block then to clamshell mounts.) as in one side is different from the other? I am having a time to get it to sit perfectly.

I am swapping to a k5 blazer tank in the rear, I am getting a diesel tank but not sure how it is different from gas, is it just doesn't have a baffle or something?

Also curious on how to run exhaust, i have the 6.5TD turbo and stock exhaust, I saw some people say to use the 6.2 ds exhaust and some say dont.