I recently purchased a disco 2 SE trying to change all the fluids as e vehicle is going to hit 100k miles. I’m very particular when it comes to certain things. I’ve worked on cars before but it’s my first time working on trucks so don’t kill me.

so my question is

how come every time I look at T6 rotella 15W-40 it says it’s for Diesel engine? What’s the reasoning for this? And is this type safe to use?

also, I want to use KN / Mobil filter but it says on autozone and advance auto parts Mobil 1-301 doesn’t fit? Can I get some explanation on this.


I feel like oil Is oil and this shouldn’t be that complicated specially if I’m going to change it every 3-5k miles


bonus question: any servicing I need to do? I read that one thread named “things if you need to when you purchase a high mileage disco” I’ll probably do all of those here soon

 

Rotella is a wide-use oil. It's ideal for my early 80s Japanese motorcycles as well as my Rover. Diesel oils do have special detergents in them but that doesn't necessarily mean that you can't use them in other engines.
As far as "oil is oil" goes... well, no.

Get yourself a copy of the RAVE manual -- search this forum for a download link -- and read through the sticky about servicing your truck. THEN start to mess with stuff.

 

the larger oil filters don't show in the system as fitting but they will. I don't know the Mobil number for sure but seems right. I have run the Wix filters in all 3 of my rovers and I've been happy with them. The Wix number is 5151 I believe, could be 1515, there is only one that is all 1s and 5s lol it's the only way I remember when I'm in the store.

 

That’s what I was thinking but yeah without getting too technical with it., feel like all the oils would work regardless.. but thanks for the input and definitely have to look into rave manual

 

Rotella 15W-40 is a good weight because the thicker oil (plus zinc and detergents) is more friendly to the engine design (which was old when the Disco 2 was brand new) plus all of the ageing that has happened since. I use a WIX 51068 which is a "standard" size oil filter, I don't quite understand the need for a larger one plus I recall reading somewhere on this forum from someone claiming to be a WIX engineer that the larger filters have a bypass valve on them of sorts that a lot of old discos aren't quite capable of opening so the filter is only partially effective. Take that last bit with a grain of salt as it was "just something I read on the internet." I can't help but think that if you are changing your oil every 3000 miles that the larger filter isn't quite needed.

 

I run the larger just for more volume, with the small hope that it allows for slightly cooler oil temps. Plus figured it can't hurt. I vaguely think I remember that thread but remember someone having oil pressure problems upon first start after a filter change. Have to make sure you fill the filter as much as you can before installing it to avoid any issues like that. I've had no problems when doing so.

 

The "larger" PH8A size (P/N strictly for reference) was used in older RRC's for years! They went with the smaller PH16 size on the D1/D2/P38, but PH8A aka the larger filter bolts right on. So the valve business I'm gonna call an urban myth especially since LR was using it first before the PH16 smaller filter. I only use the larger Mobil1 M301, K&N HP3001, Motorcraft FL1A, or Wix. DO NOT use FRAM, or the 2.99 filters.

 

Mobil M301 fits fine that is what I use. Oil for Disco's is really about the zinc content, I use royal Purple HPS 10/40 synthetic it has the zinc and the Disco likes it.

 

Appreciate everyone’s input. Finally some explaination. I’ve been trying to read up for a whole month why people would use this type of oil and oil filter. I normally just go to autozone desk and ask whichever one. But I want to make this disco 2 last. So I’m particular with oil change

 

If you don't know the history of the oil changes, and you use a high detergent oil, I would change the oil on the early side of 3,000. If the previous owner used non detergent oil, the detergent oil may dislodge some oil buildup. Change on the early side and check it for quality. If you find something, you may want to go early one more time.