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Weird differential problem

I love my low mileage 2008 Jeep Liberty that I’ve owned and driven for 10 months. I recently returned from a 40 mile round trip out of town. About 5 miles from the end of the trip, disaster struck. A sudden high pitched squeal resulted in a sudden bang from the rear end. I pulled over to investigate and I smelled the unmistakeable aroma of hot differential lubricant. I also noticed some smoking from the rear end. The Jeep was towed to a local repair shop.

Steve called me a couple of days later with some questions. He told me that the little Jeep needed a new rear end and I was expecting that. The pinion bearing had failed and had damaged the pinion and ring gear. He suggested that I replace the entire rear end as they were plentiful and fairly cheap. He gave me a price of $600 for doing the job which included the replacement rear. It sounded cheap to me so I called a couple of other shops in the area. They both were within $100 of Steve’s estimate. Steve wanted to know how 90 weight gear oil wound up in the Jeep. I asked if that was a problem and he said yes.

The Liberty used 75W90 so that probably caused the bearing failure. I told him that the car dealer did a full service on the Jeep when I bought it. I did change the engine oil to Castrol as I have used it for over 40 years going back to my racing days. He is waiting on the rear end delivery so he removed the rear drive shaft for me. I need the Jeep for small trips that are not over 40mph. The front wheel drive works great with a small grumble from the rear. It does use more gas but gas prices are around $1.50 around here due to the corona virus so it’s not too bad on the wallet. I say weird in the title because most rear ends that go bad start weeks in advance. I had at most…a 2 minute warning.

So, it’s in AWD with the rear driveshaft removed? Does any fluid come out of transfer case with driveshaft removed? I don’t know if this thing is fwd with an output shaft or if it has a transfer case.

Apparently those Jeep were recalled because of the following:

QUOTE/Received a recall letter from Chrysler regarding a recall stating that “the transfer case heat shield may drop down and rub on the drive shaft, weakening it and potentially causing the drive shaft to break.”. Chrysler’s recall letter fails to mention what is outlined in the NHTSA letter: The first potential cause of an accident resulting from the above referenced defect: “if the drive shaft breaks, a section of it can strike the transfer case tunnel with enough force that the airbag computer will believe the vehicle is in a crash and thus deploy the airbags.”. I lodged a complaint with Chrysler that they are unwilling to provide 2008 Jeep Liberty owners with alternative transportation while they “fix” the “problem”. customers need to be informed about all the possible consequences and Chrysler only mentions this the transfer case heat shield may drop down and rub on the drive shaft, weakening it and potentially causing the drive shaft to break. In addition, I spoke to Chrysler “recall help desk” about whether I should be driving my Jeep or not and I was told “you’ve been driving your car for 53,000 miles and nothings happened so probably nothing will happen but let us know if it does.” He said that the “head honchos” were meeting about the fix as we spoke. I asked him to let the CEO know that if they really cared for customer safety they would get us rental cars and that I would take the cheapest rental on the market. Would the CEO of Chrysler continue to drive a 2008 Jeep Liberty until the fix"? would he have his son, daughter or wife drive one in its present condition". NHTSA in the spirit of transparency, where is the information that tells 2008 Jeep owners how many and at what mileage accidents have occurred. I am unable to easily access this information on the NHTSA web site and am an intermediate computer user./QUOTE

  • San Rafael, CA, USA

I have had rear axles go BANG and fail. Cost lots more than $600 to replace with a used one. And yes, straight 90wt can cause exactly the failure you had, especially in short trips with cold gear oil.

The 2008 Jeep Liberty has the improved driveline. The driveshaft has 4 bolts at either end so no lubricating fluid is lost when the shaft is removed. It’s now basically a front wheel drive Jeep.