96 engine in a 94

[pkelly72]

I've got a complete running engine, transmission, and transfer case out of a 96. I know the transmission is completely different but will the 96 engine work in the 94?

My plan is to rebuild it and have it on stand by for the day that my 94 needs it.

Any advice would be appreciated.

 

[js93cruiser]

The 96 is obd2 so the heads might be different I believe the block Is the same... Not 100% on that though

 

[EvolovE]

I just recently had a 96 motor put in my 94, so yes it works. One of the sensors for OBDII is not used, and you need your 94 intake, TB, to upper intake manifold. Maybe a couple other things, I forget, but it will be obvious when you actually put the motor in. But it definitely works.

 

[pkelly72]

Thanks. I appreciate the responses.

 

[Ebag333]

Get the ECU and engine wiring harness and make your '94 OBD-II.

 

[pkelly72]

Get the ECU and engine wiring harness and make your '94 OBD-II.

That sounds like a lot of work or would I be wrong?

 

[Ebag333]

That sounds like a lot of work or would I be wrong?

Compared to pulling the engine? Seriously?

If you want to do it (and I would, I love my UltraGauge), that would be the time to do so. You'll never have as easy of access as you will with the engine pulled.

 

[pkelly72]

I see your point and I already have a scan gauge 2. Has this been done? I'll do a search.

 

[Ebag333]

I see your point and I already have a scan gauge 2. Has this been done? I'll do a search.

Not sure, but I don't see any reason why it couldn't be done.

There will be some adjustments that need to be made, you'll need to figure out how to do the O2 sensors (I'd just run a dummy/simulator for the rear, and either have a new bung welded on after the Y pipe or even use just one of the existing ones), but most of them are pretty minor/easy all told.

Actually, you'd have to run the OBD-II ECU. The newer tranny is controlled by the ECU. The tranny out of a 93-94 has it's own unit.

 

[SchniperJB]

sent you a pm.

 

[pkelly72]

I was originally just planing on rebuilding the engine and replacing mine when the time comes. The transmission and t-case were included with the engine. I never intended on swapping out my transmission but you guys are making me think.

I have a supercharger on the 94 and have always wanted to get more out of it. I know that the OBDII is the way to go.

Here's the question I have: Would it be as simple (I'm laughing at myself as I write this) as pulling my current motor and transmission with the engine harness and ECU and replacing with the 96 motor, transmission, wiring harness and ECU? Sounds to good to be true.

 

[SchniperJB]

I want to think there might be an issue with the oil pan configuration being different between 94 and 96. I will check my notes and let you know.

Others might know off the tops of their heads.

I was originally just planing on rebuilding the engine and replacing mine when the time comes. The transmission and t-case were included with the engine. I never intended on swapping out my transmission but you guys are making me think.

I have a supercharger on the 94 and have always wanted to get more out of it. I know that the OBDII is the way to go.

Here's the question I have: Would it be as simple (I'm laughing at myself as I write this) as pulling my current motor and transmission with the engine harness and ECU and replacing with the 96 motor, transmission, wiring harness and ECU? Sounds to good to be true.

 

[kirkm76]

Wasn't there something about a crank sensor...I think you had to add it (use the crank from the later engine) if you were using an early motor in a later OBDII truck but I could have it backwards. Good to know the early ones have a separate tran computer though. Easier swap age down the road.

 

[Ebag333]

I want to think there might be an issue with the oil pan configuration being different between 94 and 96. I will check my notes and let you know.

Others might know off the tops of their heads.

Wasn't there something about a crank sensor...I think you had to add it (use the crank from the later engine) if you were using an early motor in a later OBDII truck but I could have it backwards. Good to know the early ones have a separate tran computer though. Easier swap age down the road.

This.

In order to run a 93-94 motor in a 95-97 truck you need to use the upper oil pan, crankshaft oil pump drive gear and crank position sensor from the later motor. You will also need the upper intake manifold and throttle body from the later motor.

You can run a later engine in an early vehicle by using the early throttle body and upper intake. You can leave the late oil pan on it, you don't have any wiring for the crank position sensor however.

If you swap to OBD-II you'll use the newer upper intake manifold and throttle body.

 

[silverhorse]

The OBD 11 wiring harness that goes to the motor and ECU also goes to the trans plugs , so that would not plug into the older trans....

 

[pkelly72]

Silver- I understand that and that's why I was going to stick the entire engine and tranny from the 96 in my 94.

My question is aside from the ecu and harness, maf, and air intake, what would I need to do? Could
I just pull my current ecu and wiring harness from the 94 and replace it with the 96(obd2)?

 

[silverhorse]

I'm not sure? I'm in the same boat. I have the motor and trans from my rusted out 97' . I plan to install that motor(rebuilt) into my 94'. i was planning to just keep the 94' trans and T-case.
I'm really not sure why we should swap the trannys and go to OBD 11................

Is it worth the effort?

 

[pkelly72]

I'm not sure? I'm in the same boat. I have the motor and trans from my rusted out 97' . I plan to install that motor(rebuilt) into my 94'. i was planning to just keep the 94' trans and T-case.
I'm really not sure why we should swap the trannys and go to OBD 11................

Is it worth the effort?

Good question really and I'm not sure. I guess it depends on the extra work required. I've got a supercharger OBDII is supposed to help fueling during WOT. Better diagnostics and maybe even better mpg?

I even have the 96 exhaust. I understand that the ECU controls the motor and transmission (OBDII) through the engine wiring harness but what will have to be done for the ignition, seat belts, lights....all the other accessories that are not associated with the engine wiring harness or are they???

 

[TtyTyler]

I'm not sure? I'm in the same boat. I have the motor and trans from my rusted out 97' . I plan to install that motor(rebuilt) into my 94'. i was planning to just keep the 94' trans and T-case.
I'm really not sure why we should swap the trannys and go to OBD 11................

Is it worth the effort?

How did your swap work out? Harness wise, and smog?