CDL slow to disengage - normal or not? (1 Viewer)

[agaisin]

If parked/stopped, CDL goes on and off quickly.
If I engage CDL and drive a little, then disengage button while stopped it does not disengage. In fact, after driving forward a a few feet (or backwards a few feet) it still doesn't disengage immediately. Takes more driving than I expect for it to finally 'pop' off (feel like it makes almost a pop sound).

Last truck was an xterra with part time shift on the fly 4wd and I had to drive a few feet b/f it would engage/disengage but it would consistently go on and off as expected. I feel like the delay and the feet I have to drive (forward or back) to get the truck to disengage the CDL is not normal.

So what do you all say - is this normal or is something (like an actuator or some other part) on it's way out (and what is that so I can start preparing for the repair)?

How quickly/easily does it disengage for you all?

 

[bkgee]

mine seems to engage/dis pretty much without hesitation or "popping". i think the center diff is basically an electric locker (?), and the e-locker in my old tacoma sometimes would hesitate and pop. never had any problems in that truck.

i am waiting for my TRD buddies to provide me with some technical papers on the CDL as well as the ATRAC, i will post them up as soon as they get back to me... it may be a bit of a wait for that info...

 

[FullyLitLED]

I heard lack of use of the cdl will cause it to have difficulty with engaging and disengaging. I have the same problem with mine! I have to put the truck in reverse for about 10 feet before it disengages

 

[2000UZJ]

depending on usage the time to engage varies. If it was never used in 10 years it may be sticky and needs a little workout. If it's used on a regular basis it should click on off with very little distance and time.

just make sure all 4 wheels are on the ground and NOT spinning. I have hit it while off camber and out comes a giant grinding sound. Not pleasant since it's tries to engage until completed. It will just grind away.

 

[cmfhsu]

Completely normal. What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding. All of that pressure is being exerted on that locked center differential, and, in simple words, takes more than the CDL motor is capable of to disengage the lock.

In more detail, when you disengage the CDL, you don't actually force the "lock" apart, it simply stops the transfer case (center differential) from trying to lock both wheels. If there is significant binding in the driveshaft, the transfer case will be locked tight (kind of like how you can't change gears on a manual without depressing the clutch). When the transfer case is given slack, like when a wheel skips, and you hear that clunk, the transfer case finally unlocks the two axles and you can drive on your merry way. DON'T drive the car with the CDL engaged for long periods of time. It's very bad for many components, and will wear your tires down.

I have the same situation, and I'd imagine its very similar for many other people on this board. As long as you don't have issues with your CDL engaging and disengaging while not moving, you're perfectly fine.

 

[agaisin]

Completely normal. What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding. All of that pressure is being exerted on that locked center differential, and, in simple words, takes more than the CDL motor is capable of to disengage the lock.

In more detail, when you disengage the CDL, you don't actually force the "lock" apart, it simply stops the transfer case (center differential) from trying to lock both wheels. If there is significant binding in the driveshaft, the transfer case will be locked tight (kind of like how you can't change gears on a manual without depressing the clutch). When the transfer case is given slack, like when a wheel skips, and you hear that clunk, the transfer case finally unlocks the two axles and you can drive on your merry way. DON'T drive the car with the CDL engaged for long periods of time. It's very bad for many components, and will wear your tires down.

I have the same situation, and I'd imagine its very similar for many other people on this board. As long as you don't have issues with your CDL engaging and disengaging while not moving, you're perfectly fine.

Thanks for the insight - have 2 followup questions:

1) From what I remember (will confirm tomorrow), if engage while at a stop and disengage without moving in between it works fine. However, if I engage, then drive, then stop and push to disengage, it did not immediately disengage even though I was stopped (b/c I moved in between). Is this still normal or an issue?

2) You said "What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding."
I actually was driving in a straight line - still ok, or is that indicative of an issue?

 

[agaisin]

Completely normal. What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding. All of that pressure is being exerted on that locked center differential, and, in simple words, takes more than the CDL motor is capable of to disengage the lock.

Also - are you debunking the "the more it's used the more quickly it engages/disengages" theory? I had heard that b/f but wasn't sure if there's any validity to it. I know on my previous 4wd the cdl was always consistently quick (required motion to engage/disengage) regardless of how recently I had used it last - but then it may have used a different mechanism for the diff lock.

 

[cmfhsu]

Thanks for the insight - have 2 followup questions:

1) From what I remember (will confirm tomorrow), if engage while at a stop and disengage without moving in between it works fine. However, if I engage, then drive, then stop and push to disengage, it did not immediately disengage even though I was stopped (b/c I moved in between). Is this still normal or an issue?

2) You said "What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding."
I actually was driving in a straight line - still ok, or is that indicative of an issue?

In an ideal world, where all four of your tires are evenly worn, and they're all inflated to the exact same pressure-down to the decimal, that would be a problem. It would also take some superhuman concentration to keep the steering wheel perfectly straight and a perfectly smooth and even road to ensure that all four wheels spin at exactly the same speed. What you're experiencing is the drivetrain binding because, perhaps, one of your wheels is under/overinflated, or slightly misaligned, or perhaps (as our cars are not known for super-precise steering) you're turning just a few degrees in one direction. The drivetrain binds, and you're not able to unlock until there's slack.

Also - are you debunking the "the more it's used the more quickly it engages/disengages" theory? I had heard that b/f but wasn't sure if there's any validity to it. I know on my previous 4wd the cdl was always consistently quick (required motion to engage/disengage) regardless of how recently I had used it last - but then it may have used a different mechanism for the diff lock.

I'm not debunking or proving this idea. In theory, it would make sense, as anything that's not used in a long time can freeze, for one reason or another. However, I'm fairly certain that in the first 7 or so years of life of my car, the CDL button was NEVER exercised, and as of today, it's still fine.

HOWEVER, my low range selector is firmly stuck in high range, as a result of some debris that has worked its way past some seals over the 250,000 miles. This could have been prevented by working the lever, say, every week. You might as well work those two out every so often, as it doesn't take much time, and it can't possibly hurt.

Your old car had a different type of transfer case. Our cars are permanent four wheel drive cars-the engine sends power to all four wheels all the time. Your old car, I believe, had part time 4wd, where it would be RWD most of the time, and, with the push of a button, or a pull of a lever, it would lock the front and rear axles together. That 4wd was meant for sticky situations only, even when off-roading. You can't drive in 4wd all the time, on the road, as you can in our cars.

 

[lexi4darin]

1) From what I remember (will confirm tomorrow), if engage while at a stop and disengage without moving in between it works fine. However, if I engage, then drive, then stop and push to disengage, it did not immediately disengage even though I was stopped (b/c I moved in between). Is this still normal or an issue?

This is the driveline binding. The binding happens when the truck is moving and the parts build up a pressure.

2) You said "What's happening when you drive (I'm guessing it's not in a perfectly straight line) is the drivetrain is binding."
I actually was driving in a straight line - still ok, or is that indicative of an issue?[/QUOTE]
Not indicative of an issue. There are a lot of factors going when you drive that add to the CDL's ability to disengage quickly. Anyway, If you push the button to disengage and it happens within 20 seconds or less, I wouldn't be worried. Sometimes my truck disengages right away and sometimes 10-15 seconds later. I don't worry about the difference. It definitely helps to slow down to a reasonable speed before hitting the CDL button. *Also, if the center diff sticks after you've pushed the CDL button to disengage, try accelerating forward in a straight line and then slowing down to a near stop. Then repeat once or twice to help "unstick" the center diff.


*That's in your owners manual.