will the auto pcm work with a t56? how about the wiring harness?

 

Are you swapping in a complete LT1/T56, or are you doing an LT1 intake conversion on your 5.0?

I don't feel like typing, and its alot to cover both possibilities.

 

check the signature. its an lt1 swap, and will probably mated to my t5 before i get a t56.

 

I noticed your signature, but people use the words "LT1 swap" very loosely.

I'm not an LT1 expert by any means, but from my understanding, the auto and manual LT1s used the same pcm, only with different programming. You can reprogram yours with the manual settings and you'll be fine.

As far as the wiring, I would think 98% of it is fine. I think you will be missing the CAGS terminal on your harness, and reverse lockout. Pickup some wiring diagrams, and compare the two. Thats the only way to know for sure.

 

Right on.

 

ok. why would anyone want CAGS? is the reverse lockout necessary or is there a way around it?

 

Chances are you don't want CAGS. I believe you can disable that in the PCM without having to buy one of those CAGS eliminating terminals or whatever they call them.

You don't need the reverse lockout really. I have a T56 in my thirdgen, and I don't have it functional right now. The only consequence is that you have to put a bit of effort on the shifter to be able to go into reverse. There is a spring that keeps you from going into reverse accidentally (you don't want to shift into R accidendtally on the highway if you are meaning to grab 5th). In the stock LT1 factory setup, there is a solenoid on the transmission that is controlled by the pcm. When you are 5 mph or under, it allows you to go into reverse effortlessly. Otherwise, you have to fight that springs to get it into reverse.

A couple guys on this board just run a wire to the brake light switch on the brake pedal so that when they are on the brakes, they can go into reverse effortlessly. That helps, but it isn't fool proof. You can brake on the highway, and downshift from 6th to 5th. Under these circumstances, it is possible to drop into reverse without meaning to.

I'm sure that even if your harness doesn't have reverse lockout, running one would be as simple as running a wire fromt the pcm through some of the loom thats already there, and down to the tranny. Its not a difficult thing.

 

so is it still possible/easy to accidently shift in reverse accidently without the reverse lockout? thanks.

 

I don't think you caught what I was trying to say. If you hookup reverse lockout how it came out of the factory on the LT1s, you don't run the risk of shifting into reverse accidentally. The pcm won't allow you to engage reverse without alot of effort if you are going over 5 mph.If you don't hook it up at all, you also don't run the risk of shifting into reverse accidentally. It will be difficult to move the shifter into reverse all of the time because you are fighting the spring (its roughly 10 lbs of pressure to move it into reverse).

You do run that risk in the example I provided where you hookup reverse lockout to the brake light switch on the brake pedal. This method allows you to slip into reverse with ease whenever you are on the brakes. The danger with this is that sometimes you are shifting and are on the brakes (downshifting from 6th to 5th on the highway for example), and run the risk of accidentally dropping into reverse.