1994_3500_6.5 died, swaping in a 1996_3500_7.4...wiring questions...

[99xcss4]

Don't forget to scrap the Diesel torque converter in favor of one with a stall speed appropriate for a 7.4L.

No doubt there's going to be significant exhaust mods, too.

Wire harnesses, computer programming, etc., I can't help with. I wouldn't even consider that swap. If they ever start doing emissions inspections, you're gonna be screwed.

I am glad where I live I do not have emissions the truck is titled and will be registered as a 94 c2500 diesel even though it is a k2500 gas now the k2500 suburban title got turned in at the scrap yard when we scraped the suburban body back half of the frame and the front half of the c2500 pickup frame. I think in terms of legality it is not black and white. where I live i could take a S-10 and put the cab and bed on a full size 1 ton 4x4 frame frame and it would still be inshured and registered as a S-10 some state you would need a custom builder title for that but if both vehicles have nm titles before you what ever your pan is when you go to get insurance and register your creation you use the vin and title from the body if you are doing some thing like I am. as far as I know the only time you would use the title of the donor frame would be if you were making you own body.

 

[Schurkey]

From what I understand there are 2 stall speeds: 350 which got the B82 high stall and B81 standard stall came with the 454 and 6.5.

Not what I expected...but good to know.

I am glad where I live I do not have emissions

Even if there's no emissions testing NOW, which way do you suppose the EPA and the states are going to go as time goes by? Be a shame to have to scrap the truck because the law changed.

 

[99xcss4]

you are right only 1 or 2 counties in my state have emissions as far as I know the the whole state has no safety insection and while I do not see it changing any time soon dose not mean it wont whenlif it happens I think this will help https://www.ebay.com/itm/3547274372...BjeG47UxWxsZ9Y+cw0FlmF3eSg==|tkp:BFBM3J-Aq5Ji the truck dose have egr and it will remain intact truck has no evap system and unless it will be mandatory in the future along with the cat it will not get one. I do not know squat about emissions laws or then the dont mess with them that everyone knows and some ignore its seams though that obd1 laws are less strict and if emissions get stricter in my state who really know how it will be some things might be grandfathered and the big question will be will they treat it like the diesel it was born as or will they treat as a gas truck with the excetion of really strict states could get a classic plate for it and be exempt

 

[Another]

The exhaust from the gas truck has no cats, but it doesn't have a metered cat anyhow, I knew I would have to swap fuel tanks and lines so it will have factory evap. I was thinking about getting headers and a cam/ injectors while it is out. But that only works if I do the holly wiring and ecu. 1500$ and then a stand alone trans controller for another 800.

I will try to just set it up exactly how it sits in the 96 engine bay, with the 96 fuel and exhaust system too, find a wiring diagram for both 96 and 94 compair were they connect at the firewall and repin or splice. If it looks like it will not mate I will install the 96 interior side fire wall and repin and splice as needed. Make it look clean and factory. If it doesn't work ill throw the money at it.

Its one of those "show truck usa" badged 3500s crew cabs no rust and nice interior, so I think its worth the work.

 

[99xcss4]

I do not know any thing about the holley pcm and wiring but there is a cheap option for the trans it has auto lockup but you have to shift it manually https://www.ebay.com/itm/1957810817...rentrq:93d5ff791880a0da3599d056fff9d8d6|iid:1

 

[Supercharged111]

The only wiring that isn't going to marry up is the stuff that goes through the passenger firewall. The pin assignments didn't change for the driver's side, but you may find you're missing something from back then. I'd plug it in, hit the key, and see if it runs or not.

 

[Supercharged111]

If the 7.4 is coming from an automatic truck just use that PCM for the trans

 

[99xcss4]

@Supercharged111 if the OP puts the 454 where the diesel was and uses the holley wire harness and pcm to run the engine and leaves the diesel pcm and wire harness on the truck make the 4l80e function would it work for him

 

[Supercharged111]

@Supercharged111 if the OP puts the 454 where the diesel was and uses the holley wire harness and pcm to run the engine and leaves the diesel pcm and wire harness on the truck make the 4l80e function would it work for him

If he has a donor why not keep it simple and use the stock Vortec PCM?

 

[someotherguy]

If he has a donor why not keep it simple and use the stock Vortec PCM?

'96 PCM on a '94 transmission. The '94 trans has no provision for PWM on any of the solenoids

Richard