Rear Differential Locking Up

[PT-4]

Mine has actually done that once or twice. Do you have limited slip rear? I pulled a few bushes and stumps out and I guess it locked the limited slip in and when I back up I could feel it binding like I had a solid axle. Once I pulled forward again and backed up it didn’t do it again. Does your truck have park sense?

Yes, I do have parking sensors.

 

[GTyankee]

If the gears were not meshing, you would hear a clanging noise 1 time, when it breaks the binding, but that usually happens with a Manual transmission.

I too think something Brake related is causing your binding

 

[PT-4]

E-brake or rear brakes?

 

[Trail Ryder]

I believe Ram recommends servicing the differentials every 50,000 miles or so. Hopefully, you have been doing that.

 

[marks146]

Search for this stuff on Amazon. Not saying this will cure the problem, but it's worth a shot. I had some issues when turning sharply after I changed the rear diff fluid in my 2015. This cured my problems.

Genuine Mopar Fluid 4318060AC Limited Slip Additive - 4 oz. Bottle​

Manufacturer Part Number	‎4318060AC
OEM Part Number	‎04318060AB

 

[PT-4]

I believe Ram recommends servicing the differentials every 50,000 miles or so. Hopefully, you have been doing that.

Bought my truck with 70k, now has 106k. I will be getting the differentials serviced very soon.

 

[62Blazer]

So the issue basically feels like somebody throws the trans in park and the truck jerks to a stop? Or maybe like you slam on the brakes?
If this was coming from the rear axle gears it would have to be a serious failure, like metal chunks floating around inside the fluid. There are no electronic devices, actuators, etc... inside the rear axle that would somehow activate and cause a severe lock up. The only time I have seen a rear diff do this is a chunk of metal floating around in the gear oil gets jammed in the gears, and going forward for a second allows the chunk to release. However it would probably happen at other times and cause other very noticeable issues. The limited slip possibly binding would not cause a sudden lock up, especially when back straight up. If you were turning in the reverse and the limited slip was bound up the tires would still roll/spin and you would feel it, but the truck could still move with the inside tire just spinning/slipping/chirping on the pavement. Same basic comments about the transfer case. There is nothing in a transfer case that you shift to that locks it up...like a transmission has a park, but the transfer case does not.
It's kinda' hard to tell without actually being at the truck, but sounds like maybe an autopark engaging? Does this have an autobrake engagement if it senses something in reverse?

 

[PT-4]

I was wondering the same thing. I thought the rear sensors were just a warning device, not something that would actually stop the truck.

 

[Harley Harrold]

If the parking brake shoes brake friction material comes loose from the shoes they can jamb the rear rotor/s which is more likely to happen while backing up in reverse. I have heard of this happening to others.

 

[Dean2]

I was wondering the same thing. I thought the rear sensors were just a warning device, not something that would actually stop the truck.

If you have Park Sense Active Braking as an option, the sensors will stop the truck hard. Being a 2014 1500 Laramie I am betting this is the issue. The fact it backs up after shifting to drive is one of the ways to overcome the Active Braking. If the OP has this happen again easy way to tell if it is active braking, put car in park, turn off sensors, put back in R, if it backs up now, it was the sensors. Turn off your park sensors as you back out of garage as it is reading the edge of the door opening as too close. Mine alerts red on the rear sensors every time I back out, but since I have active braking turned off on my 2500 it doesn't slam on the brakes. It does if it is on. Other option, as I said above, is to turn off your rear sensors when backing out. Then it won't activate the brakes either.

Found this video that explains it real well. It is also well explained in your owners manual but no one reads those.

Park Sense Automatic Braking: How to Disable Automatic Braking

Park Sense Automatic Braking is designed to help prevent minor fender benders when maneuvering at slow speeds. However, sometimes you might want to temporar...

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