Yep. The FZJ has an oil cooler bolted to the side of the block just behind the front half exhaust manifold. Oil circulates through three thin plates that are surrounded by coolant from the water jacketin the block. In my case, a hole developed in the oil passage leading to the plate cooler allowing oil to mix with the water and water to mix with the oil. Oil is under about four times the pressure that the water is under so I was getting oil/water mix overflowing from the coolant overflow jug as well as milky colored oil in the pan. Somewhat similar symptoms to a head gasket failure but hg failures generally consume coolant, show white smoke from the exhaust, and have a sweet smell to the exhaust. Also, you can usually confirm a blown head gasket by doing a compression test. You will generally have low/no compression on one or two cylinders depending on where the gasket failed. Overheating is usually associated with head gasket failure too. It's kinda the chicken or the egg question on the whole overheating thing. Most thing overheating is a sign(symptom) ofhead gasket failure but I tend to believe poor maintenance on the cooling system may cause the overheating which leads to head gasket failure due to the uneven expansion between the head and block at high temps. Just my $.02 though. Anyway, Sherry had no overheating problem either so that's what led me to the oil cooler to look for the cause. Hope I'm right!
