2004 AWD Base Astro - DCsleeper

Obviously a typo on the 233C... since he clearly posted a photo of it.
Yes... MANY PEOPLE have done it!

It's single-handedly the BEST upgrade for the AWD! Literally direct bolt-on!
Although you do lose the advantage of "automatic AWD".. which is great for snow.
I suspect a true 4x4 conversion will be much better for someone living in NC.
I LOVE mine!

Shame about the wheels.
Some people are unfortunately good at giving wrong advice.

What part of NC?
I travel from S.Fla and have done a lot of riding over the years in western NC

Welcome!

PS: Welcome to the "white van" club too! lol

dcsleeper said:

Yes MMusicMan, your thread and others led me to this TC. When I saw a ridiculous deal on ebay for one of them I jumped on it.

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Cool! Glad to hear it.
I was also inspired by those before me.. learned a lot from people who share on this forum.
If you own an Astro.. this site is the owners manual!

I received the switch for the TC today, to replace the vacuum switch for the front axle.
It will be used to switch the PCM to 4LO as shown in other threads.

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I don't understand how that switch is supposed to work from that location.

I think I have an issue w/ the AWD, so I used that as an excuse to get a different TC.
I'll probably get the fluid changed before I swap it out. Just to see.

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What's the issue?
Swapping it out for an NP233C will certainly fix it for good!

I used to live in Franklin, but I'm now near Roanoke Rapids 95.

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I driven and ridden though Franklin MANY times!
Love the ride to Highlands (to see the waterfalls).. and of course drive though typically heading west or north.
I typically mostly stay in Murphy or Cherokee, as well as Boone, Hotsprings, Linville, Gatlinburg, and of course ride for hundreds of fantastic mountain miles in all directions! I tow my motorcycle up from South Florida several times every year for many years now. If my motorcycle isn't leaning into a curve, I feel like I'm not really riding.

Sounds like you're on the opposite side of the state now.

dcsleeper said:

The cam attached behind the actuator rod/shaft pushes directly on the switch.
You need to modify the cam to only engage for 4LO. Stock it actuates for 4wd Hi and 4wd Lo.

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I missed THAT one! I'm guessing the T-case has to be opened up to modify this cam?
Sounds like the ultimate cool idea. I've seen a lot of variations on how to externally do this switch.
Mine is on a toggle inside. I haven't ever needed it, but it's there if I ever want to utilize it.

For anyone wondering what we are talking about.. (the 233 t-case in 4-LO) the transmission only works manually in 1st and 2nd gear without the switch. Grounding this pin (any method) makes a "correction" in the computer and allows the transmission to shift "automatically" though all the gears. It is NOT essential, but you'll only have 1st and 2nd gear in 4-LO without it, which could be limiting if your are traveling in 4-LO on varying terrain.

Did I confuse you by mentioning the front axle?

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No, I understood the function of the stock vacuum switch and what it controls.
That's why I was a little baffled on how this position would be modified to work with 4-LO only.
I missed class that day! lol

The issue is: driving around, you might hear a "brappp" a second long. Sounds like a rumble strip.

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Yes my AWD did that from a standing start on mild acceleration.
No noise.. just a kind of weak shutter on take off. I once thought it was my transmission going out.
I had the bind in tight turns too.
Clearly the clutches were binding... a problem solved by flushing with correct new fluid.
I solved the problem by swapping the t-case to a 233.
I was shocked how smooth the take-off was after the swap... something I had lived with as it got worse over time.