This car was gifted to me, and I am hardly mechanically inclined, so apologies ahead of time if any of this seems ignorant.

I noticed the steering on my vehicle became rough and felt a "rubbing" during turns. Assuming it was my power steering, and after spending 10 minutes trying to figure out where the steering fluid reservoir was, I learned there really isn't one. It's my layman understanding that what I needed to top off what my Hydraulic fluid reservoir, located on the passenger side engine bay. Inspecting this reservoir, it is indeed very low. After digging for hours online, asking in Facebook groups, etc, I've found that the Castorol Hydraulic System Mineral Oil is what goes in this reservoir, and it is no longer in production. I went to local auto shops; even called a Jaguar dealership and talked to multiple people to see what kind of alternative fluid I can use. They had no clue what I was talking about. This was a bit concerning, because from what I've gathered, I need this exact fluid or else I run the risk of destroying the rubber in my breaking system, wreaking havoc on a lot of things.

I was told by someone experienced in these vehicles that any LHM brake fluid will work in this reservoir. I ordered some LHM Extra Mineral Brake Fluid from Agriteer and it arrived today. My question is twofold:
1.) Am I going to destroy my car by adding this?
2.) Assuming no, do I need the car running when I'm adding this fluid, or is it best to add without the car started?

Thanks for your help.

 

No apologies needed. Search "self leveling suspension system" in this section, you will learn all you need to know. The self leveling system ran on the Mineral oil that you refer to. The system was soooo bad.... (how bad was it?) that Jaguar themselves deleted it and reverted to "normal" coil-over shocks inb their service bulletins. You want to delete that system if it is still there- It has probably already been done. Once you've done that, "normal" power steering fluid will work fpr your power steering system. There are plenty of threads documenting the suspension delete, and once its done you have a more -or-less normal power steering system. I suggest Rock Auto for your replacement suspension -parts if you need them. Dont give up, theyre a hoot to drive once theyre sorted.
Show us some pics, do an intro. Welcome to the forums.

 

Thanks for the reply, Jerry. I can confirm that it is incredible to drive and I've never had a smoother ride! Pretty incredible for a 35 year old car. I'm not sure if there's a way to tell if the "old" system is still there or not; is there a sure way to tell before I add this fluid to the reservoir and make a big UH-OH?

Funny enough, I was googling this style vehicle earlier and came across the exact online listing where my Jag was bought:

https://www.classic.com/veh/1991-jag...0lmp?tab=specs