Difference Between a Single and Double Lip Seal

Question:

am changing wheel bearings. While removing wheel found additional sleeve with o-ring inside of seal. do you know if the o-ring goes outside of this sleeve or inside? Never seen such a part before. Trailer is about 1990 and model is 30 0118.

asked by: Len

Expert Reply:

It sounds like the remains of a double lip seal. Was it like a rubber o-ring with a metal spring around it? You are going to have to replace the seal so I would just disregard the sleeve. It would go on the outside of the rubber lip though.

I attached a picture that shows the differences between a single and double lip seal for you to check out.

The difference between the single lip and double lip seals is that the double lip grease seal will have two rubber lips that are in contact with the spindle. The double lip grease seals are usually used in marine applications to give a better seal and protect the bearings from the water, which can cause damage to them.

expert reply by: Jameson C