What is a cheap reliable 4x4?

Ok winter is creaping up and my 97 Ford Ranger 4 cyl. 2 wheel drive with 117,000 miles I'm almost positive is gonna need some work on it that's worth more then the truck itself. I've had the truck for 3 years and got it at 99,000 miles for 2 years i've been getting so many problems with it and i've taken good care of my truck with all the regular maintenence and everything. the motor and transmission run great but its everything else thats falling apart and i'm sick of spending money on it to only have another thing need fixing a month later. So i'm thinking of selling my truck as is and with about $4,000 or less get a 4x4. So should I save up a little more and just try make my truck go through one more winter or is $4000 enough to get me something that will last at least a few years. I'd like to hear your expriences and what trucks you've had luck with I'm considering possibly a jeep cherokee with the 4.0 engine