Got this service axle lockers message today and the rear locker won’t engage. It’s a ‘24 ZR2 with 1700 miles on it. Anyone else deal with this yet? It’ll be going back to the dealer this week.
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R3_ZR2
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As someone who has had 3 trucks with lockers front and rear, I will chime in.
First truck with lockers was a 2008 Dodge Power Wagon w/G-56 manual 6-speed. "Service 4wd soon " light came on. It fried itself because the "stock factory full synthetic gear oil got up to 315°F, according to 3 different thermometers. Had to completely remove ring, pinion, axles. Ended up being $4800, they tried to get me to pay it, but my lifetime Powertrain warranty trumped their newly worded warranty.
Next was our 2019 Chevrolet Colorado ZR2 diesel. "Service 4wd soon " light came on during our Ny to Cali trip. Turned out that GM Engineer's made the wiring harness about 4" too short and wires were pulled so tight that it rubbed through 4 of them and was intermittently shorting out the 4wd system. They cut all 4 wires and added 4" to them, soldered them and used heat shrink over each one. No more issues.
2023 Chevrolet Colorado ZR2, I have not had any issues yet but probably will at some point. This truck locks up the axles within a second.
The issue can come from multiple sources. If you tow, I recommend changing your gear oil every year. When you do change your gear oil, clean out the inside of differential extremely well but do not use brake cleaner, it may not be compatible with the plastic used in modules inside. The Power Wagon used the electric to activate the lockers and the electric activated a magnet. Not sure how the ZR2 works but if there is a magnet, CAREFULLY use a q-tip to clean all the silver micro metal particles off of it before you put new gear oil in. That's what creates the fault code. If the voltage or impedance changes out of its own parameters, it won't allow it to lock. The distance between the magnet and locker is also important, which is why I said to CAREFULLY clean it.
The gear oil, no matter what brand of full synthetic, used to sheer about every 12k miles, in the Power Wagon, so I changed it and cleaned the magnet every year. We towed at max weight of 10,500 lbs.
Fluid is a lot cheaper than new parts. An oil sample test costs about the same as changing your oil yourself. Hope you find someone to properly diagnose and fix your truck. Keep us posted please.
First truck with lockers was a 2008 Dodge Power Wagon w/G-56 manual 6-speed. "Service 4wd soon " light came on. It fried itself because the "stock factory full synthetic gear oil got up to 315°F, according to 3 different thermometers. Had to completely remove ring, pinion, axles. Ended up being $4800, they tried to get me to pay it, but my lifetime Powertrain warranty trumped their newly worded warranty.
Next was our 2019 Chevrolet Colorado ZR2 diesel. "Service 4wd soon " light came on during our Ny to Cali trip. Turned out that GM Engineer's made the wiring harness about 4" too short and wires were pulled so tight that it rubbed through 4 of them and was intermittently shorting out the 4wd system. They cut all 4 wires and added 4" to them, soldered them and used heat shrink over each one. No more issues.
2023 Chevrolet Colorado ZR2, I have not had any issues yet but probably will at some point. This truck locks up the axles within a second.
The issue can come from multiple sources. If you tow, I recommend changing your gear oil every year. When you do change your gear oil, clean out the inside of differential extremely well but do not use brake cleaner, it may not be compatible with the plastic used in modules inside. The Power Wagon used the electric to activate the lockers and the electric activated a magnet. Not sure how the ZR2 works but if there is a magnet, CAREFULLY use a q-tip to clean all the silver micro metal particles off of it before you put new gear oil in. That's what creates the fault code. If the voltage or impedance changes out of its own parameters, it won't allow it to lock. The distance between the magnet and locker is also important, which is why I said to CAREFULLY clean it.
The gear oil, no matter what brand of full synthetic, used to sheer about every 12k miles, in the Power Wagon, so I changed it and cleaned the magnet every year. We towed at max weight of 10,500 lbs.
Fluid is a lot cheaper than new parts. An oil sample test costs about the same as changing your oil yourself. Hope you find someone to properly diagnose and fix your truck. Keep us posted please.
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