I recently towed a camper trailer with my 91 Caravelle from Sydney to Tamworth and return. The trailer weighs 450kg max so it's not very heavy and well under what the car can tow. Strangely, when pulling up hills the auto trans develops an oil leak and the oil blows back onto the exhaust, which causes smoke to billow out the back. When I get back onto a flat road the leak stops and hence the smoke goes away after a short amount of time. This happened every time I pulled up a decent sized hill. The leak was dripping from around the front of the transmission pan area, left side corner (front of the car that is, I guess that's the rear of the transmission). I've checked the pan bolts and dipstick tube are all tight and there is no evident of any leaks now. The trans oil wasn't overfilled, Ive checked it today and it's on the low mark. Strange I know. Has anyone experienced this?