Differential Locker won't Engage

Howdy,

2023 TRD OR Automatic - About 9200 miles and for first time, as a test, I tried to engage the Rear Diff Lock and the indicator light just keeps flashing red. Truck goes into 4-Hi and 4-Lo no problem. I've engaged 4-Hi once a month or so since new, but I've never tried the Locker before.

How I tested: put in 4-Lo, move shifter to D, press Locker button, wait 30 sec for light, still flashing red, drive slowly forward a little, still flashing, drive in reverse, still flashing. I did this about 10 times. Truck warm. Truck cold. And after 20 mins on freeway to make sure really warm fluids. No difference.

This is on dry pavement, btw, as there's no area for me to test off-road or even dirt road, nearby.

Any different techniques for me to try before I take the truck into the dealer for my 10K service and have them check the function of the locker?

Thanks much for any help!

 

You need to turn some. The dogs on the engagement mechanism of the elocker are somewhat coarse and if they don't line up no amount of waiting will make it happen. You must get some differential displacement in the side gear to find the sweet spot. Especially if it's a little stiff from no use. This won't hurt a thing so typically moving forward slowly with some weaving will get it done.

 

Did you turn left or right while driving forward/reverse? Sometimes you need to do this to get it to engage. Not just straight.

Or the actuator failed... I've been needing to replace mine for 2 years not...

 

Yep, need to turn a little

 

Ah, weaving! Didn't try that but makes sense why that would help.. Will try that and report back. Thanks.

 

The slight weaving WORKED PERFECTLY !

Thanks very much, All!

 

make sure to exercise it like you do the 4wd actuator. I'm sure that's why mine failed. I used 4wd all the time over the past 14 years... only used the diff lock half a dozen and it gave out (in the locked position, lol).

 

Same, I just manually engage it once I'm at the trails

 

Still planning to get this manual actuator once the truck isn't on camper duty anymore!

 

For future readers note this is the 2nd gen locker and unlike the 3rd gen possessed by the OP.

 

Engaging//disengaging the locker and 4lo on dry pavement is always going to be tricky, because of bind up in the drivetrain. It’s best to be on low traction surface that allows the tires freedom to slip.

Locker engagement/disengagement is most reliable when rolling forward under 3mph on a low traction surface. I haven’t found that any weaving is necessary.

Do you not have any grassy areas, dirt parking lots, or road construction near you? If so, use those instead of pavement.

 

Pricey kit but I'm all about getting rid of all the electronics. The rear locker is the only electronically engaged item left in my driveline. Gonna look more into these manual engagements. Thank you for posting.

 

Lot easier than a screwdriver and some sockets.

 

Who makes this manual actuator? Very neat, didn't know this was a thing.

Edit- nevermind, sometimes the googlenator is creepy af. Was the first result in the search