Rear Diff Oil

[Zantus]

I want to change the oil in my rear diff and I've got a few bottles of 80W-90 in the shed.

Can I use it in my rear diff with factory locker?

[sierra]

9/21 in the owner's manual.
That oil should be perfect, it's only the LSD that needs a different spec.

[mff64]

Just make sure it is a GL-5 oil for diffs, transmissions and transfer take a GL-3 or 4.
I use this Castrol site as a guide http://www.datateck.com.au/lube/castr_au/

[sierra]

Just make sure it is a GL-5 oil for diffs, transmissions and transfer take a GL-3 or 4.
I use this Castrol site as a guide http://www.datateck.com.au/lube/castr_au/

Strange that the Castrol site lists the GL-5 SAE 90 oil for the 3.2 and 2.5 diffs without specifying it needs to be GL-5 SAE 90 'Hypoy LS' for the LSD in all the 2.5's and the 3.2's without diff locks?
Castrol Syntrax is an example of a GL-5 SAE 90[75w/90] diff oil that's not recommended for limited slip differentials.

[mff64]

I know what you mean , checking the TDS for each of the oils gives the best information.
I could not find a listing for the 'Hypoy LS' or 'Syntrax' and the 'Syntrax E' is a bit heavy (85w/140) and suited to Eaton, Dana and Rockwell
The LSX 90 is the LSD oil listed but Castrol say in the late model vehicles synthetic oils are recommended and the SAF-XA will suit many of these requirements. Well quess what, there is no listing for that oil .
There is the SAF-XJ for LSD's but is a 84W/140 and the SAF-XO is for open diffs but right weight 75W/90
Now where is the oils specialist/technician when you need them

[sierra]

Complicated isn't it? They have so many different 'new' products it would be easy to make a mistake.
The LSD clearly needs a special oil, other sites confirm that but with traction control becoming the norm they might soon be a thing of the past anyway?
Penrite list Limslip 90/SIN Gear 75 for the LSD and Hypoid 80W-90 for the open diffs.
I've always liked their products, it still feels like real oil and they go that extra bit with viscosity ranges and options.
eg HPR Diesel 15 is 15W-50
In fact that's how they market them now[just noticed!] Extra ten.

[mff64]

I have used a lot of Castrol over the years because it was always easy to get around here but now that BP own it they have made it a lot harder. The Castrol RX Super was always a good oil and was the only oil most trucks were running in Cummins and Cat but now days things have changed with these regurgitating engines.
I am going to try some Prolube oil that comes out of Brisbane, will be interesting as i get oil samples done through Amdel in SA.
I will have to check out the Penrite web site as i don't have any oil for the Tri yet, should be able to get some in the Isa when up there next

[sierra]

I am going to try some Prolube oil that comes out of Brisbane, will be interesting as i get oil samples done through Amdel in SA.

Do you get oil samples checked for contamination to gauge engine condition/wear?
If you do it would interesting to get any comparisons for oil brands.

[mff64]

I am sure it dose it all, 'Physical Test & FTIR'
Visc @100 c, base #, soot index %, dispersancy, water %, fuel dilution %, oxidation, nitration & glycol %

'Metal Concentration - parts per million'
calcium, magnesium, phosphorous, zinc, aluminium, iron, chromium, copper, lead, tin, silicon, sodium, boron, molybdenum, nickel, silver, titanium & vanadium

I tried a full synthetic in the 04 NP 3.2 did and it showed up that it was not heavy enough oil(5w/30)and gave a very high copper reading(from 6-7ppm to 400ppm) as well as low viscosity at 100c
So i quickly went back to the mineral 15w/40

[sierra]

mff64,

I like the pic in the shed, good looking vehicle!!!
Who's towing who?
What is the wastegate mod?

The oil analysis is very interesting. If you have the time I for one would be very interested in 2 factors.
Which brand and grade of oil does the best job in the diesels and how long can it be left in there before it's time for a change?
Very interesting results for the 5w/30. As I suspected, good for economy but bad for the engine and confirmed my 4 x 5L of 15w/50 was better stuff, especially through the summer. Semi synthetic though?

[mff64]

mff64,

I like the pic in the shed, good looking vehicle!!!
Who's towing who?
What is the wastegate mod?

I still have to put all the bits on it yet.......
The Tri did it's best, but unfortunately 20tonne against 2tonne..........
Shortened up the wastegate arm to give more boost

[snowman]

The oil analysis is very interesting. If you have the time I for one would be very interested in 2 factors.
Which brand and grade of oil does the best job in the diesels and how long can it be left in there before it's time for a change?

me too mff64!! any real knowlede in this dept would be appreciated - we ALL have to run oil so i would not see too many uninterested readers....

...maybe this can be moved to an engine oil thread though? buzz - subi.

[Aussie]

I may be of help here, I make oil, fire some questions on the thread under technical/servicing/oils aint oils

[sierra]

I may be of help here, I make oil, fire some questions

Not the rear diff but I would appreciate your expert opinion.
Mitsubishi specify a GL3 oil for the manual gearbox but it's virtually impossible to source and I ended up using Penrite Sin Manual Trans SAE 75W-85 GL-4 Plus as Penrite tech line suggested.
Mitsubishi say not to use 'commercial' oil in the gearbox but someone recently had a dealer change theirs and they used a GL-4 apparently?
I changed mine because it was noisy when hot as the clutch was released in neutral and Mitsubishi said it was 'clutch rollover' and they all do it to some extent. It doesn't with the Penrite but is still a bit rumbly in neutral when cold.
The stuff I drained at 7,000km was dirty and without substance.
When warm it's quiet and works perfectly when cold and up to temp.
The idle is so quiet with some 2T oil in the fuel tank I might be hearing noise that was always there cold in neutral?