'01 Grand Cherokee - leaks

Make sure this isn't from oil running down from the valve cover. It usually is.

Also check the oil pressure sender, it can die and spring a leak. That usually gets oil all over the place.

Can be the valve cover or pressure/level sender also, check the side of the block. I tightned the bolts just a little bit (1/16 turn) and that soved the problem for a while. Don't go more than that or you will warp the pan and cause a larger leak.

Yes. Either that or a rubber plug. The proper way is to drop the covers, clean out with a cloth, then reseal and refill. It's a messy job I usually give to my local shop.

..no..

I would find a good reputable mechanic and avoid the oil change places. They usually do more damage then anything else. Think I popped $100 to have them do both front and rear diffs on mine. (if you have a limited slip rear the cost will be a bit higher)

This is my son's - and he's been in europe since last summer. So we swap cars around every so often - lots of snow here in Chicago & the jeep comes out... My concern is the diffs going "dry", but don't know the rate of the seal leaks.. Can the plug be removed and the level checked - lube added - so nothing bad will happen, like now...

Yep. Pull the plug, stick your pinky in and you should feel the lube right at the level of the hole - generally you just add oil until it starts to run out ;-). If you decide to change it, in that climate I'd really suggest a good synthetic oil. Oh, and if you take the plug inside and get it good and warm it will go back in a lot easier.

You'll be amazed at how cold that crap is! I had to change the spider gears in the front end the winter I was in Madison, WI. Dropped the cover and the oil just sat there - like jelly. No drips, just a blob. Stuck my hand in to pull out the busted pieces and it was one of the most painful things I've every done. Instant freeze! By the time I had scraped all the broken gears and oil out I was ready to wait for Spring. Have fun ;-)

tnx - I seemed to recall the pinky tester... Our son is in Europe/Germany until June - and then UW/Madison -

Send him my best wishes. I was born in Texas then the military sent us all over the South and Central America. I saw a little cold in NJ, then Colorado and back to Texas after I went to pilot training. When I finished a tour in Vietnam in 1970, the AF sent me to UW/Madison for grad school - right in the middle of the anti-war protests. 70-odd inches of snow the first winter, 35 below temps the next winter. A lifetime of winter in two years. That was also when I got my first 4WD and started to learn about the pay-for-play principle ;-)