Putting a gas 350 in a 6.2 diesel frame, quick input please.

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AKnarrowback

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Hello and thanks for looking.

I'm in a bit of a hurry trying to research this issue.

I have the chance to buy an 82, 4wd, 4 speed stick, with a 6.2 diesel in it.

My past experience with the 6.2 diesel was not good and I am not a fan.

However.

I have a 78 suburban with a 350 gas and a 4 speed stick in it. Both are complete and running. The 82 is in exceptionaly good condition, the suburban is a 2wd rust bucket, but the motor is almost new.

I want to put the gas motor in the diesel truck. Remember I have ALL the parts since both trucks are in running condition right now.

Will the diesel bolt into the 350 engine mounts and possible mate up to the 4 speed stick already in the diesel?

I'm looking to get a basic truck again. I'm burned out on fighting the defective design of my 2017 silverado and want to go back to something I can work on with my tools on the bench and my two hands.

I realize the fuel systen, wire harness, exhaust a lot will need to be changed, but like I said, I have everything to do that. All I need to know is if it will bolt in without too much trouble.

Also guessing the differentials are a little taller geared in the diesel, but this isn't a problem since I'm not going to need a bunch of low end grunt with what I do. Besides, the gas suburban has a diesel rear end in it and got 21 mpg at 65 mph back when I drove it.

I need to have some answer ASAP since the guy selling the diesel is holding it for 24 hrs to let me do the research.

Please Friends, chime in with any wisdom you have.

Thanks in advance.

John
 

CheemsK1500

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I don’t know if the engine mounts themselves are the same, but I know transmission bell housing bolt pattern will be same between a Detroit and a SBC. The biggest thing that needs to be addressed is that you’ll either need to convert the SBC power steering pump to work with Hydroboost brakes or convert the ‘82 to vacuum assist power brakes.
 

backwoodsman

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The 6.2L uses the same engine mounts as the SBC. Should be a direct bolt-in, much as I hate seeing a 6.2L truck adulterated with a gasser. :oops: :p I put a 6.2L in a Scout II years (decades) ago, and used SBC mounts.
 

Smtty58

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I'd be concerned that you will be swapping between two eras of trucks. Big stuff like motor and trans are ok, harnesses, brakes, ect. do some research in an LMC catalog to see what parts are different.
 

Smtty58

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The 6.2L uses the same engine mounts as the SBC. Should be a direct bolt-in, much as I hate seeing a 6.2L truck adulterated with a gasser. :oops: :p I put a 6.2L in a Scout II years (decades) ago, and used SBC mounts.

Looks like he lives in Alaska, I can see why he wouldn't want a diesel. :)
 

Finkaire

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Dream in California, smog exempt!
 

Ricko1966

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I am 90% certain you are going to have everything you need. I think the 350 and 6.2 mounts are compatible. Not sure about disc and pressure plate. The bellhousing is the same and you can rob the Suburban for brake and exhaust pieces. The injection pump stop solenoid will work for HEI power the Alternator is plug and play. It's an easy swap.
 

mxer147

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My 83 was originally a diesel now burning gas 5.7 liter. The wiring is different since the diesel is fuel injected; fuel delivery different. Suspension springs heavier duty. Two batteries for the diesel. The diesel fuel mileage is twice better and louder. Having two complete runners shouldn’t be too challenging to swap; just time, dirty hands and bruised knuckles.
 

AKnarrowback

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Yes in Alaska, stranded too many times with glowp plug problems and still have tinnitus from that diesel.

Thanks for the quick answers guys!

I thought I'd "update" from my old 96 sierra, with 300k miles, to a 2017 silverado...... Already had the 6l80 burn, electric gremlins showing up weekly and now the DOD lifter tick is starting.

Been searching for a clean square body gasser with a stick, looks like I might build my forever truck. Do the DOD delete on the 17 and keep it for a trash hauler, use the 82 to trust my life with when it gets cold out.
 
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CheemsK1500

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I'd be concerned that you will be swapping between two eras of trucks. Big stuff like motor and trans are ok, harnesses, brakes, ect. do some research in an LMC catalog to see what parts are different.

With squares and even GMT400s to an extent, most of the drive-train stuff more or less “drops in” with only minor modifications sometimes being needed.

Where things get messy, is when you start mixing and matching body panels and interior bits, especially when trying to make 73-76 stuff work on 77+ stuff or vice versa. It can all be made to work one way or another, but it takes more cutting, welding and drilling. It looks like OP really only wants the engine, and not too much else out of the older truck, so he’s not in for too much of a headache.
 

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