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General ChatChat about all things Blazer (and related vehicles). Off-topic stuff should be in the lounge, and all mechanical problems should be posted in the proper forum.
I bought an 01 Blazer for a hunting/dirt road vehicle. It has the 4 button/auto transmission. I was starting to replace all the dry rotted vacuum hoses and discovered there is no vacuum switch on the transfer case. I owned a 2000 Sonoma so I knew about that switch. I've read on here about somebody with this tranny in a 99 and they spoke about some kind of vacuum switch on the firewall. I don't have one of those either. I'm feeling pretty good about this because I can't see how any of my vacuum lines can become contaminated with ATF with this set up. Am I missing something, or am right about this?
Correct about the ATF , you should not get any into that system , you should have a vacuum switch on the firewall above the distributor , If you dont it may have been removed and the 2 lines hooked up together locking the front diff 24/7.
It appears the hoses have been altered. I suspected that was the case. I would llke to have a diagram of how those hoses run and the part number for that vacuum switch if anybody just happens to have them handy. Thanks for the help!
I found these with a quick google search and they are for the firewall mounted switch
Dorman 600-104
OE # 15165891
OE # 15706341
I saved this sketch from an old post on this site, thanks to whomever gave it to us.
The hose going to the drivers fender well is going to the vacuum ball in the fender.
The one going by the steering column is going to the Hvac system.
Last edited by Strangerock; Feb 12, 2018 at 08:45 PM.
Mike5511, Here is the thread I started when I replaced the vacuum lines under the hood of my 1999 with 4-button 4wd system to which you posted with a diagram for the vacuum hoses for trucks with NVG236 transfer case. (see below) I've since posted the diagram into the first post of the thread for others who might need it. (Thanks for adding the diagram BTW)
I found these with a quick google search and they are for the firewall mounted switch
Dorman 600-104
OE # 15165891
OE # 15706341
I saved this sketch from an old post on this site, thanks to whomever gave it to us.
The hose going to the drivers fender well is going to the vacuum ball in the fender.
The one going by the steering column is going to the Hvac system.
There is a check valve involved. I believe the diagram I found is more accurate. Check it out and see what you think.
Mike5511, Here is the thread I started when I replaced the vacuum lines under the hood of my 1999 with 4-button 4wd system to which you posted with a diagram for the vacuum hoses for trucks with NVG236 transfer case. (see below) I've since posted the diagram into the first post of the thread for others who might need it. (Thanks for adding the diagram BTW)
Transfer Case Differences
