Differences between blazers with 3 button and 4 button 4wd.
 

Hey everyone

Just wanted to know what the differences are between a blazer with a 4wd switch that gives you the option of 2wd 4wd hi 4wd lo and auto 4wd as opposed to having no auto 4wd.

Is the difference only with the wiring and the TCCM or the whole transfer case is different?

I would like to take off the transfer case on a car with 3 buttons, rebuild it, and put it on mine which has 4 buttons. Will this work with absolutely 0 modifications?

Thanks

Transfer cases are different. They will bolt up the same, but that's it. Different wire harnesses, (dash & underhood), different driveshafts, different encoder motors, different fluid, 3 button has a vacuum switch on the transfer case. 4 button does not, but it does have an electro vacuum switch on firewall. TCCM is different, BCM is different, PCM is programmed differently. Other than all that...they're the same ;)