Vacuum Acuator Isn't getting suction to pull it into 4wheel drive

Hey Guys i'm new to the 4x4 world I just got my first truck. A Chevy S10 4.3L Ext. Cab 4x4 with a 3 inch body lift and 31x10's. I work on it everyday trying to make it better in some way or just clean it up. Well about 2 weeks ago i tried at 4 Wheel drive both high and low worked. Well some buddies and I went out to test drive it and ride some trails i was thrilled. My buddy led us and got stuck in a mudhole his 4 wheel drive was out so basically it was me that was suppossed to have 4x4 working well i shifted it into 4 wheel drive nothing happened come to find out my vacuum acuator was out I replaced it 2 days ago.... Well the hose isn't giving enough suction the other end of this hose is connected to my transfer case... I replaced the line last night and that took forever too still nothign better how can i get more suction out of it or what could be the problem? What should I do? My neighbor and I were going to and fix it we clamped the vacuum acuator down and it stayed in 4wheel drive but the only problem is i have to take the battery out and the tray to do that and that takes 45 mins to do but 4wheel works with that so we know that is the problem. We were thinking about just running the cable through my dash or floor next to my shifter to pull and lock it manually to put in 4wheel drive to eliminate chance of failure. Any Ideas? Thx

http://www.chevytalk.org/threads/ubbthreads.php

There are lots of great mechanical minds here at , but you might want to also check the chevy boards for answers to your S10 questions.

= North American XJ(That's a Jeep in case you didn't know) Association. :smoker:

I know but i read another thread on a Vacuum Acuator and yall had some good info a Jeep really doesn't tell me allot though lol. Its a jeep but it has internal parts too like anything else does. And if i hadn't said i had an S10 would you have put some info on it?

Well, as someone will surely mention if I don't first, there is only one JEEP and a Chevy ain't it! I can state this unequivocally as the owner of a Jeep and of a Chevy truck. Alas, my Chevy truck has the dreaded "thermal actuator" on its axle! However, if the S truck uses a vacuum system similar to the XJ's, I would advise that first you trace the vacuum line that actuates the axle motor, back to the vacuum switch on the transfer case. Check for good vacuum there. If there is, you have a leak in that line. If there's no good vacuum at the switch output, your next check should be to see if vacuum is reaching the switch. If it is, the switch is bad (or, perhaps, the linkage to the transfer case so far out of adjustment it isn't actuating the switch, less likely). If no vacuum to the switch, there's a leak between switch and engine, either in line or vacuum reservoir if you have one.

A vacuum gauge is very handy if you're going to do this, and a vacuum pump with a gauge is even handier.

And, of course, you should consider dumping that Chevy and getting something better made, such as a Jeep Cherokee....

Thx for the info Matthew the lines new so wouldn't be the problem. But i'll check the other things heh. And i cant dump my chevy its my First Vehicle Beggers Cant be Choosers but i'd take a 4x4 truck anyday over a car or 2wd truck wouldn't you =P

There is a hard line that attaches to the vacume line on the fram. Check that line too. I had one that was rusted shut.