There's a LOT of debate about this actually. I don't remember 25mm actually fitting on my 1990 740's drain plug... and I've known other's who have had this problem. Could be something as simple as tolerances in the manufacture of a wrench. I've since always used 1" box wrenches on red block Volvo drain plugs. Bentley actually specifies 1". Weird, since every other fastener on the car is definitely metric.

Go to Sears, get a 6-point 1" Craftsman combo wrench. Big and fun just to hold in your hand. Use the box end. If there are worries about rounding off the plug when loosening, you're probably over tightening the thing to begin with. If you use a copper washer, there's no need to wail on the thing when you tighten it up.

Don't use an open or adjustable anything on this... and while I own a couple of big adjustable wrenches, my take is that they don't belong in an automotive toolbox.

-Ryan
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Athens, Ohio
1990 245 DL 133k M47, Cibié E-codes, Now with working wipers!
1991 745 GL 290k (Girlfriend-mobile)
Buckeye Volvo Club

When you get the copper washers make sure you get the correct ones the screw thread is 3/4 inch and the nearest metric to that is 20 mm, so over in NZ the dealer sells 20mm which is slightly too big and if it gets off centre it can drip oil.
PITA.
Regards,
Charlie

S-P-H is spot on, get two. Use the 25mm. 1-inch = 25.4mm. Be right.

Remember to get a bunch of new copper crush washers. I have re-used them, but I probably torque down the plug too much. My nearby AutoZone et al did not have them. Take along an old one when shopping. Or do the FCP thing. Dunno their cost.

TIP If you use vinyl gloves (as do I) don't even try to grip the old filter wearing them. The full filter will quickly slip, invert and dump all over the motor mount and other things I like to keep fairly clean.

Good Luck,

Bob

:>)

25mm is best. on 1/2 drive is good too.

personally, i wouldn't the standard (1") socket though it'll surely fit.

the drain plug is one thing you dont wanna round off.

tip: next time you make a parts purchase score an extra d.plug cause they're cheap.
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