How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Gm Tech (Cam) Your Own Question
Gm Tech (Cam)
Gm Tech (Cam), GMC Mechanic
Category: GMC
Satisfied Customers: 29573
Experience:  GM Grand Master Technician 2007. 14 year experience.
Type Your GMC Question Here...
Gm Tech (Cam) is online now
A new question is answered every 9 seconds

Chevrolet S10 Blazer 4x4: Vaccum routing for transfer case

Customer Question

Vaccum routing for transfer case 1994 s10 blazer
Submitted: 5 years ago.
Category: GMC
Expert:  Gary replied 5 years ago.
here is the diagramgraphic
Customer: replied 5 years ago.
Relist: Incomplete answer.
Looking for detailed routing diagram of transfer case switch vacuum lines for 1994 s10 blazer 4x4 w vortex engine LT Tahoe package. Was given quick response but only limited info 1 diagram w no explanation as requested. Tried several attempts to get addition info but have not. Paid for detailed info, got general info
Expert:  Gm Tech (Cam) replied 5 years ago.
Hello, I'm Cam. Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please be detailed.
Sorry, we cannot see the other information you requested, what more are you needing?

What issue is present with your 4wd ssytem?
Customer: replied 5 years ago.
Hello Cam, I
I have 1994 S10 Blazer, the vacuum line from the transfer case have degraded and been pulled off the transfer case vacuum switch. I have the new switch but am unable to reconnect it because all the lines have been streched and wrapped around the axle. I know there were 3 lines coming off the switch, one of the line I believe went to a tee creating a total of 4 vacuum lines. I need to replace the lines and need a good diagram or verbal description of where each of these lines go. From the switch to their respective termination points. The vehicle has the vortex engine and the LT Tahoe package. Vehicle has been off the road since we discovered the problem. Thank you
Expert:  Gm Tech (Cam) replied 5 years ago.
Ok that kind of diagram is not easy to come by so if you want we can work through it and figure this out.

So do you have the switch out of the transfer case? We need to identify the ports.
Customer: replied 5 years ago.
Yes, have the new switch. It is a dorman 600-500. There are 3 ports in a triangle pattern.
Expert:  Gm Tech (Cam) replied 5 years ago.
OK, so here is what you need to do. with the switch loose, meaning not pressed, one port is plugged, that is the one that gets vacum.
Then with the switch pushed, a different port is plugged, that is a vent to release the vacuum and by default the third port goes to the front diff actuator, does this make sense?
Customer: replied 5 years ago.
Expert:  Gm Tech (Cam) replied 5 years ago.
OK, are you able to try that and let me know if that works?
Customer: replied 5 years ago.
The diagram I have shows 1port going to the engine vacuum, 1 going to a vent and 1going to the actuator. Other info I got was that 1 line terminates under the battery actuator? 1 to the intake engine vacuum? and the other to the firewall the vent? That accounts for 3 but there are 4 broken ends hanging from the transmission on the underside of the vehicle and 1 extra short hose that had a tee
Expert:  Gm Tech (Cam) replied 5 years ago.
OK the 4th is liekly just the case vent. This only needs the 3 lines.
The one under the battery is where the actuator is for the front diff.
Customer: replied 5 years ago.
Looks like the 3 lines from the switch can be accounted for, the 4th one came off a tee from one of the line from the switch, about a foot away from the switch. Question is which line had the tee? Have to look at it tomorrow, dark now. Thanks for your time and assistance.
Expert:  Gm Tech (Cam) replied 5 years ago.
Ok that should be the vacuum source. THat is the same line that is used for the inside HVAC controls.
Gm Tech (Cam), GMC Mechanic
Category: GMC
Satisfied Customers: 29573
Experience: GM Grand Master Technician 2007. 14 year experience.
Gm Tech (Cam) and 4 other GMC Specialists are ready to help you