Astro AWD to 4WD conversion thread

[Heading Out]

OK I posted this here because I'm considering changing our Bravada over from AWD to 4WD with a proper low range.
and I believe the drive train is very similar to the Astro.

Specifics are.
94 Olds Bravada,(S-10 Blazer) last year of the square body.
4.3 vortec
4 sp OD Trans
231 AWD TC
G80 in the rear.

I'd like to use the electronic shift transfer case and add the switches rather than a shifter and linkage, as I'd like to
change the interior as little as possible.

The truck is a DD and used for exploring the Mojave and the Owens Valley mostly, light off road, no rock crawling.
I have the Jeep for the harder stuff.

where we live we don't need the AWD so I'd like to loose that and gain 4low.

What I'm looking for is info from some of the folks here who have done this swap
What factory parts did you use (year model)?
what custom parts?
Problems you ran into.

I've looked over some of the build threads, but thought I ask for some feed back.

[T.Low]

I swapped my 2003 awd Astro NP136 for a NP233C from a donor '98 s10 Balzer (no typo intended). With the electronic shift, having the donor vehicle is key because the TCCM was impossible to find for me until I found a complete donor. Witht eh vehicle, I had the tccm, the harness, and the switch.

The only issue I had was that the clocking on the 233 was slighly off from the original 136, so the front shaft would have hit the crossmember, but my BiL made quick work of it.

And my Brother has an All Data program so he could look up the wiring diagram from the Balzer and it's 233.


Crap..I was going to post pics from my photobucket (they're 4 yrs old, so they are not on this laptop) but I can't figure out to post from a host site onto the updated Expo.

Here's a link to my ASV thread; excuse all the bs, the details begin on page two.
http://astrosafarivans.org/bb2/viewt...hp?f=21&t=2586

There are plenty of other threads on ASV about transfer case swaps.

[Heading Out]

T.Low

Thanks, that's the kind of info I'm looking for...

I'll check that out

So for the Bravada, I should get the transfercase and the crossmember from a 4wd, Did you change the front drive shaft or did you keep the AWD f. shaft.

also I know the 4WD has a front axle disconnect, do you just run the AWD front axle and let it free wheel?

Thanks for your input....

John

[T.Low]

I did not need to change the drive shaft, and I did not opt for the axle disconnect. Yeah, I just let the awd drive axle free wheel.

[Heading Out]

OK
I thought that I'd just let the front end free wheel.
it seems to be be ok with the AWD front drive shaft.

I've driven the truck with the front drive shaft out and it binds much less on sharp turns.