is there oil inside the speedometer?

[vash]

with the targa top off today in bright sunlight, i noticed an oily wetness on the bottom edge of my speedometer. i wiped my finger across it and it is definately some type of oil. the tiny white letters "VDO" along the bottom of the speedo are slightly discoloured in the same oily color. what gives?

[ischmitz]

It might be that the oil or lube used on the gears has over the years condensated on the face. Even though its vapor pressure is very low it still does evaporate

Ingo

[TRE Cup]

if your car is an older mechanical speedo 911 (74 or earlier) it could be that the speedo cable is sending oil from a leaky seal all the way into the speedo. Ingo's suggestion is a good clue as well, but we rarely see that even when 110 degree days would liquify any grease in the instrument- usually we see a small spotting around the odometer opening. Put the car up on the lift, have the speedo nut un done on the trans nose cone, and look at the cable with a strong lamp. if any oil comes dripping out, then the speedo drive seals , on the trans, are to blame

[vash]

trecup, no kidding? i have an 75. so it will not apply? damn that is an oil leak at a whole new level...!

[fintstone]

Unfixed...it applies to you too, you have a mechanical speedo just like a '74. Unless you are sure it is new, I would think that a more likely scenario is that your car has had a noisy or erratic speedo or speedo cable in the past and a dufus previous owner squirted oil or wd-40 in there.