jimk403

I noticed something about my axle disconnect, it doesn't. At least not in the garage with the engine off and no tires. Turn the pass side hub by hand and the drivesahft turns. The purpose of the disco is to disengage the front driveline, is it not?
If this thing is vacuum operated, is vacuum required to engage it or disengage?
Perhaps this explains my crappy mileage, 13.5 mpg avg hand calculated.
Any idea where I should start troubleshooting?
Thanks.

Big Smoky

I'd go with either the posi loc cable to engage and disengage manually. Or do manual locking hubs. I had the CAD!

phox_mulder

Having a non Cad truck, I'm not sure, but I think vacuum both engages and disengages it.


phox

BRET LIVELY

Vacuum Moves It
The Needs To Be Running

zulusafari

Does it disengage/engage everytime the key is turned off? Therefore, it requires vacuum to remain disengaged? I am also having lower than expected mileage. Perhaps mine is stuck, too? But wouldn't the front end buck during tight turns on dry pavement, like when I have the T-case engaged in 4x4??

mrclean

No, it does not. There are two vac hoses on the CAD. When you shift to 4WD, vacuum is supplied to one of the vac lines, engaging the CAD. It will stay engaged until you shift to 2WD, vacuum is supplied to the other hose, disconnecting the CAD. The vacuum actuators do commonly fail. Pull the unit off the axle to check it. Easiest way is use a vacuum gun directly on the can, see if the shift fork moves. Lacking a vac gun, run the engine and get a helper to shift the t-case between 4wd and 2wd, look for movement of the fork. HTH

zulusafari

Cool. I will take it apart and check it out!

jimk403

That is the info I needed to know. Thank you.