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Why not Auto Trac?

1659 Views 11 Replies 7 Participants Last post by  Whifflebat
I'm thinking of doing a straight axle in my 99 ECSB. I hear that you need to change out the auto trac transfer case. :think:

I've looked under my truck and in 2wd the drive shaft doesn't turn. So my thought was if I did this and used 4wd I would have to lock the hubs and put it in 4WD all at the same time, and everything would work fine. :imo

I know I'll never have the use of AutoTrac again but Its Gay anyways. Please let me in on anyones knowledge about this subject. BTW how do you go about the ABS Brakes Issue.

This Forum :rocking:
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· Registered
72 Posts
Discussion Starter · #6 ·
Yea The front Drive shaft doesn't turn unless its in 4wd of some sort. :think: I even had the wife drive the truck with me looking. When the truck is in park you can spin the drive shaft freely. :argh: Is this normal?

And it does have the AutoTrac Button. :rolleyes: So I know I'm not too Crazy!lol

I'm gonna have to go look again. :stupidme:

What do you guys know about the ABS?

· Drive It Like Ya Stole It
7,517 Posts
no it should not spin, thats one of teh reasons you cant use it. Also the case kinda freaks out when it doesnt sence the actuator there.

ABS - fuck it, rip it out, you will no longer have the sensors on the front wheels so it wont work right at all. I cant tell you how all of this goes until the weekend when I test drive mine though, so keep tuned!

· heavy on the skinny pedal
1,960 Posts
then house come all the older chevys i see don't have the front shaft spinning when driving in 2 wheel? or is it that the auto trac case spins at all times when driving and the old the older t-cases such as np 205 203 208 don't spin all the time. and house come when i went to the dealer to get a new switch there computer listed my case as a np 208?

· Registered
3,083 Posts

NP246 - nbs trucks - autotrac - front shaft always spins

NP241(88-98 1/2 ton trucks), NP208, NP205 - - non autotrac, manual shift - front shaft spins only in 4x4

NP203 - old trucks - full time 4x4, i'm assuming the shaft always spins.
1 - 12 of 12 Posts
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