s10 4wd 4.3 1992 question

my 4 wheel will engage on the shifter and the driveshaft turns and it gears low and high the back tires but i still get no 4wheel .Is there an electric part or wire that may not be working ? The truck goes into

Don

Don, electronic or manual 4wd? Also, in 2wd does the short 'slip shaft' to the front differential turn different? I mean, to clearify, in my terms, is the short shaft free in 2wd and in 4wd is it 'locked in? This will help locate which end(ie front diff or transfer case)your problem is in. Reading your question it seems that you seem to say the slip shaft is locking in in 4wd. If thats the case and no 4wd, I believe that the servo(under Battery tray) is either not receiving the vacuum from the transfer case(hose or transfer case switch issue)or if the servo is receiving vacuum, then the servo is messed up(usually visual-rubber boot ripped). Or the cable to the front differential is set up. Or lastly a problem in the front differential. Good snipped-for-privacy@peru-motors.com

snipped-for-privacy@gmail.com wrote:

OK...dont these have vacuum activated wheel hubs?

I know my 89 S-Blazer did..and they (or the valving) are prone to failure.

That would make the front driveshaft turn, but the front wheels wouldn't.

I have seen aftermarket repair kits for these...maybe JC whitney? (keep your comments to yourself)

Check out

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You can find diagrams of how it works and flowcharts on how to troubleshoot it.

--Don Don Byrer Commercial Pilot / CFI Student Electronics Technician, RADAR/Data/Comm @ CLE Amateur Radio KJ5KB

"I have slipped the surly bonds of earth; now if I can just land without bending the gear..." "I know what it sounds like....when doves cry" (Bird Strike 8/29/05)