Understanding why there's no 4wd - 92 K1500

[Flatcap]

Greetings from Scotland! Late last year I bought my truck down in England and quickly became clear that she has had a hard life. Nonetheless, it ran good travelling up to our new home on a farm in Scotland where I had my first reason to use the 4wd. Guess what? I didn't work! Its the standard 350 auto and the shift lever seems to move ok between ranges (not the push button model). Looking under the truck I noticed the front prop turns freely whilst in park which I imagine is normal so where do you think I should begin tracking down the problem? All advice gladly received!

 

[alpinecrick]

Most common culprit is the thermal actuator on the front axle.

What year of truck? K1500 or K2500?

 

[618 Syndicate]

@Pinger is in Scotland too, he may have some input for you.

 

[Flatcap]

Most common culprit is the thermal actuator on the front axle.

What year of truck? K1500 or K2500?

Its a 92 K1500

 

[alpinecrick]

Its a 92 K1500

I’m trying to remember the 91 I used to own with floor shift.....

Does your floor shift have lights on the console? Does the light blink when shifted into 4hi or 4lo?

 

[Hipster]

Check for power at the front actuator. There is also a switch located on the topside of the transfer case. The plug/switch is prone to corrosion/deterioration from heat/age. When my plug fell apart from being brittle it cut power to the actuator.

 

[yevgenievich]

Front actuator often is a problem. Can either be replaced with a new style actuator or a manual pull cable set up

 

[Schurkey]

http://www.automotiveforums.com/vbulletin/showthread.php?t=1079737

 

[alpinecrick]

http://www.automotiveforums.com/vbulletin/showthread.php?t=1079737

Yes, the electric actuator is generally better--no maddening 3-6 second delay in axle engagement like the thermal actuator (when it's new--longer delay as time goes by). Downside to the electric version is it doesn't like to be immersed. Had to go through a bodacious puddle 16"-18" deep a few years ago, almost got stuck, backed out and after a couple tries made it through. Sometime after that I noticed the 4wd wasn't engaged. Rather inconvenient when up in the hills 30 miles from town.

The problem is Dorman doesn't see fit to seal the seam where the two halves of the actuator are riveted together. Some Devcon Plastic Welder epoxy smeared into the seam and a zip tie as tight as I could get it has successfully kept the water out for the last 3 years (knocking on wood....)

 

[Flatcap]

Thanks for all the replies gents. Will order one now & get back with how it all went!