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s-10 transfercase swap?

11K views 22 replies 12 participants last post by  AllOutofBubblegum 
#1 ·
I searched and found nothing on this, so I'll ask it hear.
What is the possibility of swapping an S-10 transfer case into a 2000 Astro?
1) What are the mechanical issues, drive lines to differentials?
2) What are the electrical issues? (and things like speedometer cables)
I get tired of this electronic AWD system going out and wondered how hard it would be to have a full 4x4 system with low range.

Thanks for any & all info
 
#2 ·
There are a couple threads about this. At least one member swapped in the NP236, which is the S-10/Blazer/Jimmy 4x4 version of the AWD transfer case in the Astro. He put the switch in the unused switch panel on the gauge surround. Can't remember his username, though...

And Silverbullet (I think) has a 4x4 case installed with no lever at the moment.
 
#3 ·
Leeann_93 said:
There are a couple threads about this. At least one member swapped in the NP236, which is the S-10/Blazer/Jimmy 4x4 version of the AWD transfer case in the Astro. He put the switch in the unused switch panel on the gauge surround. Can't remember his username, though...

And Silverbullet (I think) has a 4x4 case installed with no lever at the moment.
I have a 233. Bullet has Borg Warner or 136
 
#4 ·
thegreenmachine said:
Leeann_93 said:
There are a couple threads about this. At least one member swapped in the NP236, which is the S-10/Blazer/Jimmy 4x4 version of the AWD transfer case in the Astro. He put the switch in the unused switch panel on the gauge surround. Can't remember his username, though...

And Silverbullet (I think) has a 4x4 case installed with no lever at the moment.
I have a 233. Bullet has Borg Warner or 136
I am still running the standard 97 AWD T-Case....
 
#6 ·
There are a couple threads on this.... "Shane's ongoing lift" thread in the Builds section shows the mechanical installation, and my thread "Wiring the 233 T-case" shows how to do the Blazer electrical switch install, if you're inclined that way.... I believe there are other threads, but those'll get ya going....

It is doable, but there are tradeoffs - such as the loss of seamless traction anytime that is so well-loved in snowy climates - so may not be for you, depending on circumstance....

Read on and you shall know more than you thought to ask...
 
#12 ·
I'm cheap.

Still have yet to open my beer advent calendar. Saving that for New Years.

"To alcohol!! The cause of, and solution to, most of life's problems"
Homer J. Simpson.
 
#14 ·
I am also running a NP233 transfer case ( 2nd one though ). If you swap, then you need to understand that 4x4 is for snow, dirt and mud, not dry pavement. Also, engagement/disengagement is limited to around 20 mph or less since the front axle is still locked full time ( unless you swap in all of the S-10 axle components for disengagement ).
 
#15 ·
redfury said:
I am also running a NP233 transfer case ( 2nd one though ). If you swap, then you need to understand that 4x4 is for snow, dirt and mud, not dry pavement. Also, engagement/disengagement is limited to around 20 mph or less since the front axle is still locked full time ( unless you swap in all of the S-10 axle components for disengagement ).
I have a np233c in my 03 awd. I have it converted to manual shift.

Curious what you mean by this? The front is full time locked when engaged?
 
#16 ·
redfury said:
I am also running a NP233 transfer case ( 2nd one though ). If you swap, then you need to understand that 4x4 is for snow, dirt and mud, not dry pavement. Also, engagement/disengagement is limited to around 20 mph or less since the front axle is still locked full time ( unless you swap in all of the S-10 axle components for disengagement ).
So, will it not lock any higher? I have locked in tcase at 50..it wasn't easy but as long as the axles were at the same speed..it did it.
 
#17 ·
Just a note I am surprised how many that have T-case in their Pickups/S-10/Blazer/Jimmy and what not wanting to switch to our astro AWD transfer cases just as bad as we want theirs..
Never know may be able to find someone to do a straight across transfer case swap costing you nothing just saying!
 
#18 ·
The front axle on our vans is always engaged, the driveshaft is spinning at the speed it would locked with the front axle. Engaging a 4wd transfer case like that is like shifting without synchros in a manual transmission...except you can't double clutch a transfer case. There is no slip in the transfer case to allow it to catch up with the front axle. Disengagement is usually the bigger problem. It may come partially off the gear, but not always all the way due to binding and you'll end up with a nice big boom under your seat when it finally is forced to disengage. I recommend only using 4wd in this set up on wet, icy, snowy or dirt roads. Dry pavement will eat it up eventually, and really....why do you need 4wd on dry pavement?
 
#19 ·
If you look at the top of the transfer case, there is a triple vacuum connection that controls the front differential engagement on the S-10's. To do it right, you'd need to strip all of the vacuum harness, vacuum actuator and passenger side of the front axle to have a front diff that would disengage and engage in synch with the transfer case.

The best case to get would be the newer 4 button T case with auto select, it's basically an AWD transfer case with 4Lo.
 
#21 ·
AllOutofBubblegum said:
Are we talking the hubs are engaged full time, as in the axles are always spinning even in 2wd?.
I'd say yes... even in 2wd. Even when AWD is not engaged.. the front hubs are still connected > still turning the front axles > still turning the front pinion > still turning the front driveshaft > still turning the front half of the transfer case. Meanwhile the back half of the transfer case is also still turning from engine output. Both sides in the transfer case are simply are not physically connected.. but everything everywhere is still all turning! The drag remains the same.

The only advantage to uncoupling the AWD would be to reduce wear in the transfer case due to subtle variations between front and rear..particularly in turning.

I can't speak regarding the S10 setup.
 
#22 ·
Are we talking the hubs are engaged full time, as in the axles are always spinning even in 2wd?
Yes, the hubs are always engaged in the AWD Astro.... The diff is an open diff, however, so the hubs are not locked to each other as such...

The S-10 setup as mentioned above has a disconnect in the RH axle which disengages the RH hub, allowing the diff to stop spinning
 
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