Regular or "High-Mileage" oil

[JoesSHO]

I've been wondering if there is any advantage to using "High Mileage" oils in the SHO motor. My car has 165,000 miles on it, and runs great. Wondering if using a product like Castrol GTX "High Mileage" lubricants would be good to help conditionmy seals, etc., or if it is a waste of money.

I'm planning on an oil change after changing my valve cover gaskets, and I have a jug of Castrol GTX regular, and a jug of Castrol GTX "High Mileage" sitting in my garage and can't decide which one to put in the car...

Also- I can fit a FL-1A into an MTX, correct?

 

[TYSHO]

Castrol GTX High Milage will help, but do not expect it to start working on the first oil change. It took me 2 oil changes[5W-30], plus topping off, to actually notice how much oil I was saving.

 

[oh_SHO]

I FL-1A will work on an MTX. I have used it on mine before with no problems.

 

[JoesSHO]

Thanks

I'll throw in the GTX High Mileage this time, and exchange the regular GTX for HM jug when I go back to Wally World.

Thanks for the FL-1A answer too, I thought I had ised them on my MTX before, but it was a while ago, and I also had an ATX in there, and couldn't remember...