6.5 turbo diesel to 350 tbi swap i need help

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Big RED Burban

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ok just warning yall ahead of time this is gonna be a long post because I have a lot of questions and I'm sailing in uncharted waters

now that the disclaimer is out of the way my buddy has a 1995 Silverado k2500 4x4 6lug with a 6.5 turbo diesel and the motor is screwed so he has decided to swap in a 350 tbi and ive agreed to help him

on to the questions
1 transmission: are there any differences in the wiring of the transmissions between diesel and gas engine trucks, in other words will the harness for the trans that's in the truck plug in to the 350 tbi pcm
also are there any differences in the torque converter between diesel and gas transmissions

2 brakes: the truck is set up with hydraboost my question is will the power steering pump on the 350 be powerful enough to run the hydraboost

3 fuel pump: I am assuming that we will have to put a gas fuel pump in the tank, as far as the factory lift pump can I just leave it in line and unplug it or do I have remove it

and I know we will have to do something about the exhaust but that's not a big issue and we live in sc so emissions aint a problem

I know its a lot to read and I don't expect any one person to answer all my questions so just put the number of the question you are answering in your reply I'm gonna take this opportunity to thank all of you for your help you will really be helping us out of a bind thank you
 

TylerZ281500

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same trans bolt pattern, wiring will have to be done to run the engine in the first place and a tune or chip to control both the engine and trans needs to be made.

hydroboost will hold fine, id look into using the 6.5s power steering pump though. otherwise i run hydroboost on my 350 that originally had vacuum brakes right now with the stock pump.

as for fueling, whats a 6.5 run for a pump, electric? mech? what pressure?
 

Big RED Burban

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I know ill have to plug in a engine and trans wiring harness from a gas truck I was just trying to make sure that all of the sensors solenoids ect on the trans that's in the truck will plug up to a gas wiring harness and computer

thanks for the response on the hydraboost that's a big help

we are basically trying to do this swap as if it came with a 350 tbi from the factory so we will be getting tbi harness pcm and anything else we will need from a junkyard truck from what I can tell this will mostly be plug n play I just want to make sure there are no differences electronically speaking between the transmissions used in gas and diesel trucks so that I know the tbi pcm will control the transmission
 

Claybreaker

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I've gone the opposite way in a couple of trucks, most recently a 97 2dr Tahoe from a 5.7 to 6.2 and I have allway swapped out dash, engine harnesses and instrument clusters. You would need a donnor.
 

Big RED Burban

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yeah our donor is going to be the local pull a part, since you've done this in reverse did the diesel harness just plug in to the trans without having to change anything
 

Jrgunn5150

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ok so ill need a converter out of a gas truck

isn't the shift programing in the pcm


The converter is lower stall, but if you offroad or haul, I'd keep the diesel converter. As for the programming, yes the electronic programming is in the PCM, but the valvebody is also mechanically programmed, which is what you change when you do a shift kit.

Now a 4L60E has no governor or kickdown cable, but I bet the valvebody is calibrated differently nonetheless. I don't think it will matter, if anything, it will just have higher pressures at lower rpm's.
 

Big RED Burban

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ok so do you think we could get by with the diesel shift programing cause this is getting done on a tight budget
 
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