4WD doesn't work. whats the problem?

[Flicktitty]

Truck - 1992 Chevy 1500 4x4.

my dad has had this truck since about 96 or so and i got it about 4 years ago. and the truck has been pretty damn good, but it's always been kind of tempermental when it comes to the 4wd working.

Sometimes it engages sometimes it doesn't. I've noticed if i put it in 4wd and then shut the truck off when i start it after sitting for a while it sometimes works.

But odviously since i'd like to go somewhere right now the 4 wheel drive won't work. making a regular cab stepside truck usless.

Is it a vaccum line to/from the transfer case? I've heard of switches going out randomly that make the 4wd work. Bad transfer case? Btw this has the floor mounted 4x4 not a push button.

whatcah guys think?

[Windsors 03 Cobra]

Probably the horse dung TLA that locks the front axle in.

[Memphis]

Theres a vacuum switch on the transfer case and there is an actuator in the front axle. My money is on the actuator, but besides those two issues, you could have a vacuum hose leak or a broken wire also...Highly doubt you have a t-case issue.

[Memphis]

Probably the horse dung TLA that locks the front axle in.

lol, yep thats a nice way of describing it I guess.

[Flicktitty]

lol, yep thats a nice way of describing it I guess.

Thanks guys, think tomarrow i'll crawl under it and see if any of the hoses/lines are bad.
if nothing else might have to call around to find a new acuator.

[Memphis]

They're easy to find, just put one in my 90 the other day.

[DSMDuDE]

did some reserch for ya on alldata, check this out and see whatcha think

http://www.junkvr4.com/flicktitty/alldata/

[Russ Jerome]

Without breaking down the diagnostics here is my list
for GM actuated 4WD failures:

Weatherpack connector a few inchs from the electric
motor on the front axle, corroded terminals from salt.
Simply but connect and bypass. A weak connection
here will kill the actuator motor over time.

Actual motor, 1-1/8" wrench to remove and bench test.

The T-case switch last, let me know if you need the actual
breakdown of flow if you get that far.

In a pinch direct (fused) power to the actuator will feed
a solid 13v to the motor running, will slowly engage and
stay engaged until correct repair is made.

[Flicktitty]

did some reserch for ya on alldata, check this out and see whatcha think

http://www.junkvr4.com/flicktitty/alldata/

Thanks Nick, that helped a ton. I think thats gonna be the problem.


Without breaking down the diagnostics here is my list
for GM actuated 4WD failures:

Weatherpack connector a few inchs from the electric
motor on the front axle, corroded terminals from salt.
Simply but connect and bypass. A weak connection
here will kill the actuator motor over time.

Actual motor, 1-1/8" wrench to remove and bench test.

The T-case switch last, let me know if you need the actual
breakdown of flow if you get that far.

In a pinch direct (fused) power to the actuator will feed
a solid 13v to the motor running, will slowly engage and
stay engaged until correct repair is made.

Thanks Russ. i'll let ya know if i need any help.

[DSMDuDE]

Thanks Nick, that helped a ton. I think thats gonna be the problem.



Thanks Russ. i'll let ya know if i need any help.

np, i have full access to alldata if u need anymore info