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Where does 4wd disengage? Any help?

When I engage 4wd (pushbutton) does it engage at the transfer case, or at the front differential? Should the front driveshaft spin in 2 wheel drive? I'm trying to troubleshoot a problem with my 97 truck 4wd not engaging. I can hear it trying to engage, but the light just blinks and it doesn't engage. What is the most likely thing to break? I don't see any vacuum lines underneath. The transmission will shift into low range, but no 4wd. I'm thinking that if the front driveline is spinning in 4wd, then the problem is probably in the front differential/hubs. Thanks for any help.

Reply to
shastapat
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Both!

Usually you have to be slightly moving to fully engage both the iffy electronic engaging t-case and the engagement gear in the front drive. The light blinking usually means it isn't slipping into place and after a few seconds it aborts the attempt and stays in 2wd.

As for the front driveshaft spinning in 2wd...are you talking going down the road its spinning or at a stand still you can/cant spin it by hand?

The actuator is the piece that I know of that needs replacement most often. The electric motor that is used to engage/disengage the transfer case is also a weak link.

Reply to
Shades

Truck OFF in Park in 2 wheel yes the shaft will spin by hand

to check differential engagement

Truck in 4x4 start truck move truck a few feet put truck in PARK Block the BACK WHEELS Raise one of the Front wheels ( left side for ease) turn Wheel by hand Front Driveshaft should move , If Not that Switch isnot engaging Front Axles . I'm trying to

Reply to
no one

Reply to
Mike Levy

Full size it is probably a bad actuator on the front axle. The older ones were just a wax pellet type that heated up and moved the engagement pawl. Replace it with the newer motor driven unit and you should see a BIG difference.

S-Series uses a vacuum actuator and cable to pull the lever.

Reply to
Steve W.

It is a full size k series. big block Thanks !

Reply to
shastapat

Thanks! I will try these tests this weekend.

Reply to
shastapat

This is why I like my 2 wheel drive truck because I never have any of these problems.

Reply to
Fred Fartalot

When they make a 2 wheel drive that goes in snow and mud like a 4 wheel drive I'll buy it.

Brian

Reply to
el Diablo

No U Have different Problems ..

Reply to
no one

I always carry lots of weight in the back and if I put chains on the wheels it goes more places than 4 wheel drive trucks.

Reply to
Fred Fartalot

What are you smoking?

Reply to
el Diablo

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