Hypothetical Swap Question

Here is a hypothetical question. Say you have two complete Roadys. Roady A is donor, has 67,000 miles. Recipient B has mechanical cooling, as well as other limited features A does not. So say the engine and transmission is swapped in to B, which PCM to use? And the VATS associated to PCM, reprogram?

So the PCM on OBDII, parameters exist for Body Control Module? (power door locks) Is there a parameter for mechanical cooling vs. all electric? Reprogram B's PCM, or swap in A's and change over VAT's chip, using existing key cut pattern? I am really torn here. My recipient's trans is starting to growl sitting and starting in reverse and first. Neutral it stops. Fluid is real brown.

This is sort of a Groucho Marx moment... Goal is to have a tow worthy Roady. A's red interior is already being swapped for B's tan.

The door locks have nothing to do with the VATS or computer.

The programming for the electric fans may already be present in both computers.

The computer only gets an input from the VATS, it does not need reprogrammed when moved from one car to another for the VATS input.

If you are moving the VATS system from one car to another, move the column lock with the VATS system.

so vats "receiver" is isolated from pcm? And everything being equal, pcm goes with engine/trans, turnkey?

Pretty much, except the 96 engine and computer are real OBDII. The 94-95 are an orphan to some extent, but interchangeable for the most part.

The trans from 96 won't direct swap with a 94-95. I'm not sure why, but I asked this previously and was told its a no go without a headache.

Deadmanonduty, You are correct,you cant swap transmission years because as I was told,different year transmissions use different solenoids and if I remember correctly the 96 trans has 2 more solenoids than the earlier years. ed

Assuming he can take anything he needs from the 96, Is making that trans work in the older car still impossible?

Roadagon wrote:

Deadmanonduty, You are correct,you cant swap transmission years because as I was told,different year transmissions use different solenoids and if I remember correctly the 96 trans has 2 more solenoids than the earlier years.  ed

I could understand not being directly swapped into a 94-95 by itself, but it isnt swappable even if the 96 motor goes with it?

I believe that if you swapped everything: engine, trans, wiring harness, and the computer, it should work. It really does not matter if you have the electric or engine driven fan. You should also check the wiring to make sure there are no differences at the interface(s) with the rest of the car.

Since you haven't yet told us the year of the second car, we'll have to guess it is also a '96 based on the vehicles listed in your signature. If you want informed answers, you have to ask informed questions.

Put the 67K engine and/or trans into the 109K vehicle and be done with it. Move the existing mechanical fan hardware from the recipient car onto the replacement engine.

That's it.

Leave the PCM / electric fan / column / ignition key / VATS module alone.

BTW:

There is no BCM on the B-body's.

The VATS module is separate from the PCM - it sends a generic signal to the PCM to enable the injectors & closes the theft deterrent relay so the starter motor will operate when requested.

Column switch only reads the key - doesn't matter what resistor key is inserted.

A PCM for a mechanical fan car will not have the proper programming to operate the electric fans as they were intended.

- J

Deadmanonduty wrote:

The trans from 96 won't direct swap with a 94-95.  I'm not sure why, but I asked this previously and was told its a no go without a headache.  

Works fine. For me at least.  I swapped an entire drivetrain (engine and trans) from a 96 into a 95 and it's still working fine 30K miles later.  I did have to change out the tailshaft housing though...took a couple of mins to unbolt it and swap it. That was so the harness plug would plug right in.  

I believe Pat did the swap as well.