Some motor oil is leaking on it slowly. What product should I use to clean the rubber so that it does not cause the rubber to damage or wear out faster? I had the axle replaced a year ago and don't want it to go bad again too soon.

Relax … it’s a CV boot. It’s, for the most part, designed to withstand some fairly harsh conditions.

I find that blue Dawn and water works quite well for most things.

I agree with Tb, Dawn is an excellent oil/grease breaker without being harsh on anything else.

Another product I also use is Simple Green's HD PRO concentrate, sold in a gallon jug at Home Depot.

Even when I dilute it 3 parts water to 1 part concentrate, it pulls all the oil out of my hands and they crack open. I only use this with gloves on now. SAFE on aluminum as well, like Dawn.

https://www.homedepot.com/p/Simple-G...3421/100550784

To clean excessive mud and road rime, I use an old product named Ru-Glyde. It is a tire lubricant mostly used for mounting tires. I make it an annual ritual to clean CV boots exposed to off-roading conditions. It cleans and helps to condition boot material. I buff it dry after use. Sometimes I use it to rejuvenate old bushings and grommets that are no longer available. I keep it in a squirt bottle. A gallon usually lasts 7 years.

• Ready to use tire mounting lubricant, no mixing necessary!
• Protects against bead damage and help seat tire beads properly on the rim
• Will not cause rust or tires to slip after mounting and balancing
• Removes rubber squeals in bushing and grommets
• Restores new look to floormats, tires, and upholstery