CDL Disengaging with Clunk/Thud (1 Viewer)

[04UZJ100]

I was driving my wife’s LX today and doing the regular actuation of 4Lo and the CDL. Typically, I engage and disengage the CDL while driving/coasting on a straight road less than 30mph. The CDL engaged well and quickly each time today; however, it was taking longer to disengage. Each time it did so, there was an audible clunk that you could hear and feel throughout the car. Minor but definitely something getting hung up.

Previous actuations of the system were essentially seamless. The only thing I can think of is I currently have the spare tire on which is full tread on the driver side rear position. The other rear tire is worn but only by a few 1/16”s of an inch. I cannot imagine this slight rolling diameter difference would manifest itself while actuating the CDL.

I actuated the system 3 times but did not want to mess with it longer. I could not tell if the clunk was coming from the rear differential (driveline slack etc) or from the center differential itself.

TIA

 

[bloc]

Probably harmless.

One idea to see if it’s binding from a driveline speed mismatch.. jack one tire slightly in the air (rear is easiest), transmission in neutral, then engage/disengage the CDL and see whether the thud persists.

That small amount of tire wear shouldn’t be an issue but something as simple as uneven inflation pressure can cause an rpm (per mile) difference.. and suddenly you may have a slight driveline mismatch.

 

[04UZJ100]

Probably harmless.

One idea to see if it’s binding from a driveline speed mismatch.. jack one tire slightly in the air (rear is easiest), transmission in neutral, then engage/disengage the CDL and see whether the thud persists.

That small amount of tire wear shouldn’t be an issue but something as simple as uneven inflation pressure can cause an rpm (per mile) difference.. and suddenly you may have a slight driveline mismatch.

Appreciate the help. In that situation - what are the changes everything is aligned internally when I jack the car to ensure the actuator engages and disengages with no wheel rotation?

 

[bloc]

Appreciate the help. In that situation - what are the changes everything is aligned internally when I jack the car to ensure the actuator engages and disengages with no wheel rotation?

That’s the idea of having the transmission in neutral. I guess I didn’t mention parking brake off.

This will allow the tire in the air to spin slightly if needed to make sure there is no resistance to alignment.. and more importantly, no load on the CDL coupler before disengagement.

Spin that tire back and forth slightly while engaged if you want. You will find some free play, but it’ll stop once the driveline are loaded up against the other three tires being on the ground.

You can also spin it some with the CDL disengaged, to see what the torsen center diff resistance feels like.