Changing the RDA and PTU Lubricant in a 2011 Jeep Patriot

How did we ever get stuff done before the Internet, I ask only partially rhetorically? When it comes to vehicle maintenance, I have relied on Haynes and Chilton manuals for decades, and with few exceptions they have never failed me. However, when I looked up information on changing the Rear Drive Assembly (RDA) and Power Transfer Unit (PTU) lubricant in my 2011 Jeep Patriot Latitude, the manual was useless.

Fortunately, a few kind souls posted photos, videos, and written advice on the best way to accomplish the task. As good as the information was, I could not find a good photo of exactly where the drain and fill plug are on the PTU (front wheel drive). Therefore, to return the favor provided by others, I was sure to take some good, clear shots of the drain and fill plug location on both the RDA and the PTU.

One of the much-appreciated bits of advice found on a websites was to buy a gear lube pump for getting the lubricant into the fill hole. I bought one at Walmart for less than $5. It screwed right onto the neck of quart-size 80W90 oil container and worked perfectly.

My Patriot had a little more than 64,000 miles on it when I did the lube change. As you can see from the photos, it was very clean and looked almost new. There were only a very few fine metal shavings on the magnet area of the drain plug. I took that as a good sign of normal wear on the gears. There was no indication of leakage anywhere.

While being among messy petroleum products, I decided to go ahead and do an engine oil change after finishing the RDA and PTU. The absolute ease with which the drain and fill plugs came out of both gear boxes was completely opposite of trying to get the oil pan drain plug out. The last oil change (3,200 miles ago) was done by the Chrysler dealer, and the mechanic must have used an impact wrench set at 100 lb/ft of torque to put it in. I rounded the corners with the combination wrench, and even my large Vise-Grips couldn't grab tightly enough to budge the plug. I was afraid the %^@! head was going to wring off or that the oil pan was going to strip. In the past when a bolt head or nut was this bad, I would grind it off with a cut-off disk, but that was not an option here with so much at stake (potentially needing to replace the oil pan).

In a desperate state, I grabbed the #7 Craftsman Bolt-Out and cautiously hammered it onto the rounded bolt head as far as I dared. Then, with a box-end wrench putting torque on it, I pounded it using moderate force with the hammer, and after about a dozen strokes, it suddenly rotated. I though for sure either the Bolt-Out had slipped or the threads had stripped, but to my utter delight and relief, it had actually loosened the bolt - Yay! The way-too-small 13 mm head on the factory drain plug was replaced with a Dorman model with a 15 mm head obtained from Advance Auto for a mere $3.

Well, hopefully this story will be helpful to someone else out there looking for info. Thanks for reading.

Posted December 15, 2018