Did you replace the actuator itself yet with the new one? I think that is your best bet at this point. Of course there is always the chance of a wiring issue.

 

The new actuator never showed up. Have to re order it. So I got it to pass the test now. And now I'm getting g only 1 code saying clutch position not learnt.
I'm assuming i need a new actuator.
​​​​​​Any other tips?

 

You may... But I would get some miles on it. It may be something I mentioned in this thread, and it has been a while, but I think my second replacement generated that code even after replacement for a short while. I have not had any codes for a long time not, even with some pretty adventurous off-roading. So for now, I would say just drive it and see if it "settles" down. Also there is a software update that should be applied via the GAP tool. I doubt yours has been updated.

 

installed the new actuator from Amazon. calibration worked and no codes. Locker functions as it should.

 

Awesome! That was certainly a bit of a project. But finding that gear out of place was certainly the key or none of this would have ever worked right!

 

On the plus side I'm very fast at removing the actuator. Lol. Had it on and off 4 times. So strange how the old one was bad but still "seemed" to be working. Guess there is a lot going on in there besides just spinning.
At least we now know that removing that bolt doesn't mean destroyed diff. It must have been like that for some time and lots of miles.
​​​​​Thanks for all the help. I'm still going to get the upstate for the diff ecu program but currently have zero faults in any ecu. Any other ecu updates worth getting?

 

The transmission update for the "California stop" is good to have if yours has not been updated. Read up on the GAP tool how to make a list you can email to yourself telling you what ECUs have updates available. Some updates are on the tool already and are thus free.

 

First off, thanks for this thread. Been a help trying to figure things out for the locking diff on my 08' L322 SC. I'm getting the squeal of death, which has been happening for a few months now. With winter finally gone I'd like to get the actuator replaced before anything serious happens. I'm looking at just replacing the actuator motor as that looks like it's a lot easier to complete and less chance of introducing foreign material into the diff.

From you pictures DakotaTraveler, it doesn't look like the gear, the one that is directly attached to the motor shaft, is keyed in anyway? I assume the calibration just jogs the motor until a certain resistance is met (when the half gear meets the pin, orange gear #7 from post #26) and stores that as the stop point?

Also, where did you buy your actuator from? Trying to decide if I should buy OE (still $350), or one of the ones off of eBay/Amazon ($100).

 

@CroztheBoz - Did you do the software update? That is a critical step before replacing the actuator. But your assumptions are correct in how it seems to work. I covered in my own thread, probably linked in this one some place, that I went aftermarket. The first one, which I still have, appeared to be defective as I still had issues BUT with different codes. The company, selling on eBay, was super nice in sending a free replacement with no return on the other one. That second one was much better but if I recall I did have some faults after putting it in. Yet unlike the first, those faults sorta just went away. I think on the first it was a combination of faults and on the second it was only that it was detecting slipping - which made me feel the clutches got toasted. But like I said, they faults just sorta went away and I have had NONE since. And I have been in some pretty sloppy situations so the diff is getting a workout for sure. Yet I love heading home after and thinking, wow... not a single fault with the truck on this trip.

So advice is get OEM of course. If mine goes out again, I will only got OEM. LR Direct is a good price usually w/shipping form the UK. But if on a budget, maybe the aftermarket are worth the gamble. I would say go Amazon though. I simply lucked out with a good eBay seller, but that is not usually the case. But with Amazon, you can return anything even if it says not accepted - just have to push the chat bot a little. For reference, the eBay seller I got mine from was "turitrade" / "https://www.ebay.com/str/bbbestparts" and I paid $150. They still sell them and for less than what I paid.

 

Thanks for the info. Frustrating as there is little to no information, especially when it comes to suppliers and quality for these parts. Then add the fact that it's either $600+ (most are $800) for genuine, or $100 for a (possibly) questionable part. There exists nothing between the two extremes really, although I did find a supposed OE supplier for the motor at europaparts for roughly $300, so I guess I'll give that a try. It's the only middle of the road option I could find.

Does look like my RDCM is running a (very?) out of date version 7H42-4C045-AB which needs to go to 7H42-4C045-AD. Wonder if there is some sort of changelog for these updates. Would be nice to know exactly what parameters and behaviors are being changed.