On my 91 940SE the oil lines are all steel tubing with a connection between the oil cooler and the oil filter at the harmonic balancer. I just break the fitting loose and let the oil drain into the pan. Using this method, I have found that there is very little oil running out of the oil filter when removed.

Maybe Volvo use rubber hoses on earlier models but I could see problems developing as the rubber ages. The same think can occur on those turbos that use water cooling for the oil instead of a air cooled oil cooler.

I got a replacement engine for my sedan that has the water cooled feature, but I will switch it over to an air cooled oil cooler. I personally think that is a better design as stated before about the rubber aging and getting hard.

That's my $.02

91 940SE sedan and wagon