I have a leaky wheel seal on my trailer. I found one on my shelf that I know has been sitting there at least 5 years. Do these things go bad just sitting on the shelf? (Stemco 372-7099)
I can't say for sure, but I can say I replaced a steer axle seal in January with a 10 year old seal and it is still holding up.
HA! I bet the seal you get from the parts place is at least that old. Seals on axles don't just "go bad". Usually, its oil contamination from a bearing going south.
I use old nos stuff all the time without problems. My most recent wheel seals I replaced was on my ‘65 White wrecker two summers ago. Proprietary White made Steer axle hub Stemco seals I got from a guy were 40 years old in their original boxes. Old numbers out of production for probably that long. They still installed and Sealed as they should. All good. Put the boxes in a display case as a history piece.
Open the box, check the metal part of the seal for surface rust. If it's rusty, do not use. Gently massage the seal material and check it is still pliable and returns to shape with no signs of dry rotting. I would say these are good to sit for many many years.
