Trailblazer 4WD front axle disconnect inside view of activation

Here is seen a 4wd front axle disconnect with one side removed so the action can be seen. The small bungee cord and socket provide the spring pressure needed to insure proper movement of the shift fork.

[@James_WTFox]

I’m sure you didn’t think this would ever be applied to a 4wd twin turbo dragcar mustang lmao. But this is exactly what I needed to see. I’m going to weld the front diff but need to retain the disconnect to turn the car still.

[@jalton9416]

Good demonstration of how it works. I just finished replacing one on my daughter's boyfriend's trailblazer.

[@paultomlinson2695]

So cool 🙂

[@Lifegoeson-nv9jv]

Not bad to replace them.. make sure grease them...

[@macknumber9]

So the inner gear is permanently connected to the intermediate shaft splines and the outter gear is permanently attached to the cv shaft...these do not move...what moves is the collar sleeve...the collar sleeve moves forward so it is connected to both the inner and outer gears allowing the axle to then be connected? Is this correct?

[@thomasjbaker7688]

Pretty much, yes. Each gear is splined to a shaft, either the intermediate shaft or the CV axle shaft. Each gear has teeth on the outside diameters and these teeth get coupled together by the collar that is moved by the shift fork driven by the actuator. The actuator (at least an original one) has a coil spring inside so if the external teeth of the gears are not aligned and the shift collar cannot easily slide over the mismatched gears then the coil spring of the actuator compresses allowing the actuator to go full travel. When there is a little movement of either of the 2 gears and the teeth move into alignment the coil spring will move the shift fork and collar coupling the gears together.

[@Cornell28]

That's sweet

[@arthurjohnson5321]

The video was good does anybody know where you can get inside and outside replacement seals for the damn thing

[@kennygee2715]

rock auto.

[@IkeCoblentz]

Hi I'm looking at this on mine. If I can spin one front tire and the other does not spin could it be this box? I can push in to engage with my finger but it doesn't connect to the other wheel.

[@thomasjbaker7688]

You might need to push in where the actuator pushes in, using something like a long screwdriver, and slowly turn the passenger wheel at the same time so the two gears get lined up. If you can push all the way in where the actuator pushes, and spin the front passenger wheel, with neither the drivers side wheel nor the front propshaft (between the transfer case and front differential) turns then it is possible that this disconnect has something broken inside. But it could also be something broken on the front differentail.

[@IkeCoblentz]

@@thomasjbaker7688 Thanks for responding! I took that disconnect off and opened it and it's fine. I guessing it's the diff that's messed up but it's new it was replaced last month. But the transfer case and front driveshaft lock up so It almost has to be the diff

[@thomasjbaker7688]

@@IkeCoblentz Maybe drain the front differential fluid and check for metals? Are all the splines OK on the CV shafts and intermediate shaft?

[@IkeCoblentz]

@@thomasjbaker7688 Yes the splines look fine. Ok I'll look for metal

[@innovativeintelligence4172]

So what pins do I have to hit to get it to retract? Mine seems to have a problem retracting, I can get it to extend fine.

[@thomasjbaker7688]

The actuator is powered by the brown wire at terminal D and a black ground wire at terminal B. The actuator control wire is the blue wire at terminal A. When that is grounded the actuator should extend. When that blue wire is not grounded the actuator should retract. If it does not retract then check that the blue wire is not worn somewhere and grounding out.

[@MrDeathlik]

How work transfer case encoder motor, how to set the correct position? what resistance should the TCCM see in 2HI mode? Thank you

[@thomasjbaker7688]

The encoder sensor is a voltage divider circuit. The TCCM supplies 5 volts across the senaor and the voltage seen at the sensor signal wire is what the TCCM needs to see. At this link you can find the voltages for each position as well as the position for the motor/sensor. gmtnation.com/forums/threads/transfer-case-bench-testing-np226.21830/post-611951