7.3 into 1984 chevy k20

Earlier this summer I picked up an old chevy k20 from my local barber over in Michigan. The truck used to be a D.O.T highway truck and was physically abused. After the hard life of being a highway truck is became a wood hauler for the rest of its life until now! I picked it up for 700 bucks it's dented and was a little rusty but was $700 so I couldn't argue with that. I put new cab corners on it and am in the process of painting right now, John Deere blitz black. Currently it has a bone stock sbc 350 with a th350 trans the motor runs ok and trans is fine but not a diesel and mainly not an idi. I also picked up a 7.3 idi non turbo for $200 with a burned up 2wd c6. Later this summer My brother and I found another 7.3 with a 2wd ZF5 in a junk dually and bought that for 500 bucks as a parts truck and couldn't see another good running idi sent to the scrap yard.

My plan is to pull the sbc out of my chevy and replace it with the 7.3 idi. Would a ZF5 and a divorced transfer case work good ? This would be my daily driver year round and is there anything I need to know before getting neck deep into this swap?



Any advice would be be greatly appreciated.

Thanks Jay

I've done several mis-matched drivetrain swaps in my four wheelin' days. I think you are on the right track by swapping the whole engine, trans and t-case. Let your driveshafts be the "adapters" and use common junkyard available parts to get it done on the cheap. My days of dumping cash into aftermarket one-off parts are long gone. I think you'll need to dig up an old chevy divorced case because the front pumkin will be on the wrong side.
My only thought is that a beat up and abused truck might not be the best starting point for a daily driver rig. I do understand that if it's all you can afford, then it's all you can afford but as we used to say, " A free jeep is the most expensive jeep you can get". If you are going to invest all those hours into your rig make sure you start with the best you can afford. if it was a trail rig, beater truck then go for it, but I dont want to see you waste time trying to turn a junker into a daily driver.
good luck

Your not the only one with a chevy / corn binder combo. We have a member on here with a crew cab Chevy dually with a idi. Maybe he will chime in later.

You do know that you can yank the small block and plop a 6.2 into it without changing anything but the radiator,right?

94f450sd said:

You do know that you can yank the small block and plop a 6.2 into it without changing anything but the radiator,right?

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Say no.....say no.....say no...........don't do it.....6.2s are junk.....

94f450sd said:

You do know that you can yank the small block and plop a 6.2 into it without changing anything but the radiator,right?

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Yeah but why would he want to? The 6.2 was slightly better than the 5.7 but not by much. Putting a 7.3 into that Chevy would be pretty cool and might also make it closer to being a real truck.

If it were me, I would look into putting a ford 208 input into a gm 208, to keep trans t case married. I hate divorced set ups. just my opinion though.

Married is easier, but his ZF is a 2wd. Lots of 70s Dodges had divorced pass drop 205 t-cases and they can usually be had pretty cheap.
Travis..

94f450sd said:

You do know that you can yank the small block and plop a 6.2 into it without changing anything but the radiator,right?

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And torque converter.

The 6.2 wasnt a bad motor.they just didnt have any balls.they were meant for fuel mileage more than power.

Yeah I thought about doing a 6.2 but if I'm going to put a diesel in, it would be the 7.3

Nothing wrong with divorced, but you need to make sure all of your driveshaft angles are correct when you build your mounts or you'll have vibes. A friend of mine with a Dodge divorced had to sometimes line up the input and outputs when putting it back into 2hi because it would vibe from the in and out being out of phase. Not really a big deal. I had a 71 Dodge with a factory divorced set up and never experienced any issues, but it was 100% stock and in really good condition.
Travis..

nothing's wrong or bad, it's just more complicated to get it fabbed up.
If you want to run a ford t-case you'll have to redo the front end and that will be even more complicated than a divorced case.

I'll second 94F450, there's nothing wrong with a 6.2. I turned wrenches on plenty of them during my military days. idk for sure, but I bet you can turn up the fuel like our motors. They use nearly the same ip's. Hell, you could find a low milage, low rust military blazer for what you already spent on parts.

IDIDieselJay said:

Yeah I thought about doing a 6.2 but if I'm going to put a diesel in, it would be the idi and does anybody have a 4wd trans that's a manual for a 7.3 ? Otherwise what's wrong with divorced setup.?

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Just to clarify when you mention an idi instead of the 6.2. The 6.2 is also an idi, in fact most all passenger diesels of yesteryear from GM all the way through VW, were indirect injection.
I totally agree with using an IH motor, instead of the 6.2. If you were wanting a large diesel passenger car, than the light duty GM stuff would be fine but as far as a truck goes, I would want something a little more up to task.

nj_m715 said:

nothing's wrong or bad, it's just more complicated to get it fabbed up.
If you want to run a ford t-case you'll have to redo the front end and that will be even more complicated than a divorced case.

I'll second 94F450, there's nothing wrong with a 6.2. I turned wrenches on plenty of them during my military days. idk for sure, but I bet you can turn up the fuel like our motors. They use nearly the same ip's. Hell, you could find a low milage, low rust military blazer for what you already spent on parts.

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In my 20+ years of workin on cars and trucks i have only had to mess with 2 6.2s.you can turn the fuel up just like the 7.3.the ip is almost identical to the ford,made by the same company,the chevy turns the opposite direction.and yes,military surplus is the way to buy a blazer thats worth rebuilding.any other way of buying one and there wont be a piece of savable sheet metal on it.they were serious rot boxes.there aint a piece on them that doesnt need replacement.

The reason THat I hate divorced set ups is because of one particular truck. Lots of power in a highboy, every thing moves under power, it was impossible to be vibration free.

Why do these threads always turn into a 6.2 vs 7.3 debate? This is a 6.9 7.3 forum.