Kahlis

Just installed a 4.7 Stroker I built, rebuilt 42RE and NP231 in my ailing '96 Grand 2WD. Only problem I've ran into is a transmission plug that doesn't mate with the factory harness. Since most all Jeeps are plug-n-play, I'm surprised a male plug isn't hanging out, waiting to be used.


The female plug is located on the t-case, and appears to be a two-prong style. I was up working late but didn't take any photos. Since every other plug has a mate, I'm assuming this missing one may not be readily available as her life started as a 2WD.


Any ideas?

Kahlis

My roommate snapped a photo before going on watch.

J_E

That is for the 4wd indicator light.

Kahlis

So more or less pointless.

J_E

Without knowing whether the ECU uses that as an input on the 4wd models, it is difficult to say whether or not it is useless.

That being said, if the ECU does make adjustments based on whether or not the transfer case is in a 4wd mode, they will most likely be small changes that would be difficult to detect without a scan tool.

Personally, I would get the pigtail to plug the switch and tie the wires up out of the way. If you then decide that it is worth the effort to wire it in later on, you wont have to replace the switch and will already have the pigtail.

Kahlis

True, however, where does the 4WD plug lead - computer or dash light indicator? The overall harness (from ECU) is one massive plug which the wires branch off to their corresponding receiving end.

J_E

On a ZJ, I haven't the foggiest. Your best bet is to look through a wiring schematic for your year. Odds are good that a 2WD ECM wont have the programming to do anything with that signal, if that is where it goes. And a 2WD dash will probably not have the provision for the light. So making it function either way is more work that it is worth.

I forget where, but I did see a thread where that switch was wired to a smiley face that would light up when in 4wd.

*EDIT* I have to ask... Why on earth are you putting a 42re behind a 4.7L stroker? The 42re fails when it is behind the 4.0L and I am not even sure that the 44re internals in a 42re would make it strong enough. It's your choice, but I think you might be setting yourself up for a big headache.

Kahlis

The 42RE is what I had to work with. However, I took it to a local shop who did a full rebuild and even replaced a few prone-to-early-fail components and a beefier shift kit. By no means am I knowledgeable on transmission internals, but I believe one item known to fail is a nylon bushing or shaft - it was replaced with steel.

Bustedback

Don't worry about it. The ECM doesn't care if you're in 2wd or 4wd.

Kahlis

Thought so. Tks.