I have a 2017 SVR and am looking at doing a fluid change on the front and rear diffs. From what I can determine there are two different types of fluid that need to be used. Can anyone verify that these are the correct two? I know there are other fluids but I like Liqui Moly so this question is just about the two listed below.

Liqui Moly 20042 - Fully Synthetic Hypoid Gear Oil (GL5) LS is used in the rear diff? Can it also be used in the front diff?

Liqui Moly 22090 - Fully Synthetic Hypoid Gear Oil (GL4/5) (75W/90) is used in the front diff, but can not be used in the rear diff?

I'm always second guessing about what fluids to put in this car so any assistance would be appreciated.

 

The rear e-diff in the Type R and SVR requires a VERY specific oil. The only accepted oil according to Jag is Castrol BOT720. There's several threads on this. Concensus is don't try to use anything else, it will cause problems. Also note, only use this in the rear. The center and front diffs use a different oil (Castrol SAF-XO - 75W/90 or Liqui Moly SAE 75W/90 / GL5 if I recall).

I did a diff oil change on my Type R at 43k miles. I also did an inspection of the rear diff vent to ensure it wasn't clogged. Clogging of this vent is a known issue, and if it clogs, you get pressurization of the diff on heating which can blow out the rotating shaft seals (not good), which leads to leaks, fluid loss, and possible diff failure (also not good). FYI.

 

I must question the first part of your statement.
For both the e-diff on the R and SVR and the mechanical LSD on the S the recommended fluid is Castrol BOT 720, so I reckon whatever works for the S would also work for the R.
Two or three years ago now I had the diff fluid replaced on my S but not with BOT 720, instead I used Motul Gear 300 LS.
Zero problems with the diff since and if anything the fluid change eliminated a slight diff whine.
I went with the Motul because it is readily available here in Oz while the BOT720 is yet another type of Jag Unobtainium only available by import from OS, and the Motul was a helluva lot cheaper than any BOT 720 I could find.
This was after I did a heap of research on alternatives to the BOT 720 and the Motul brew ticked all boxes.

 

The e-diff is a very different unit than the mechanical LSD. You may wish to do a bit of research here about the e-diff: it's one of just a few weak points in the Type R/SVR. Many reports of failure, so much so that a member here has published detailed evaluations and recommendations (link below), and is looking at offering a rebuild service. His recommendations and teardowns are very useful. Based on this and other reports of failure, the universal recommendation has been to use the factory recommended BOT 720.

Of course, it's your car. Fill it with whatever you'd like.

https://www.jaguarforums.com/forum/f...repair-279407/

 

I still believe pretty much all the JLR specified/recommended fluids are nothing but marketing hype based on a commercial agreement between JLR and Castrol, and any and every fluid which meets the basic spec will be perfectly OK.
Thing is I have NEVER used any of the specified/recommended fluids in any of my Jags (2010 XFS, 2010 XFR and 2014 F-Type V6 S), and that includes engine oil, diff fluid, coolant and PAS fluid (I haven't yet changed the trans fluid but I have 12 litres of Penrite fluid sitting by), and I have never had a mechanical problem on any of those cars save the dreaded SC coupler rattle on the F-Type (fixed under warranty).

 

I used Red Line 75W-90 GL-5 in mine (mechanical LSD). The original oil wasn't bad enough that I noticed any difference in operation. Note that there are two flavors, LSD and not.

I can't speak to the front diff oil since I do not have one.