85 300D rear end
 

Hello

I have some whining from my differential. I backed it up on ramps today and had a look.. I didnt see any obvious drain plug to check fluid level. All I saw is a very large hex bolt on the back, like 17mm or something ridiculous. I got my 80W-90 gear oil all ready...

John

That is the drain plug. To unsrcew it you need a 14mm hex key.

Are you bringing the 85 on Saturday???

Yep!

The rear drain and fill plugs are 14MM hex. Sears doesn't carry a 14MM. I got mine from Grainger for about $13.75. Its a Proto brand. Note: If a monkey used to work on your car, most likely the combo oil pan/diff wrench that Performance Products sells for $29.00 won't work. I think I had to put about 125 ft./lbs on the thing to loosen it. 40 ft./lbs. is the correct fastening torque.

Trak Auto has the 14mm Hex socket for something like 6 or 7 bucks. Works great!