Do I really need to use a special oil in the tube is there any other oils that will serve the purpose?

Maybe I have something in my workshop already

Any oil will do.

I was hoping to hear those words. Make sense. Thanks

The original struts used special oil. Aftermarket strut insert replacements don't need any oil. Not sure what you're working on.

p.s. if you click Signature, put stuff in the box, and save it, it will show up at the bottom of your posts.

https://www.classiczcars.com/settings/

A little doesn’t hurt to prevent rust in the tube.

I'm installing new KYB's

I like the idea of a light coating of lube on the inner walls.

KYB is pretty specific about using no oil, but many people (including me) defy that recommendation and use some anyway.

Since you aren't using the oil primarily for lubrication, but instead, more for rust prevention, I would recommend an R&O oil. That means "Rust and Oxidation". R&O oils have additives intended to minimize R&O. Here's a couple links for info:

https://www.valvolineglobal.com/en/r-and-o-oils/
https://www.phillips66lubricants.com/product/multipurpose-r-o-oil-mining/

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