Can someone out there with an S2000 shop manual confirm what type of lubricant to put in the differential?

Mine is making a bit of noise occasionally and I think that changing it out would help (plus I've read the prior posts about the mucky sludge that comes out....ick!). Also is there any sort of additive required? I recall on my old Formula's limited slip diff that it needed an additive of some sort to quell the moaning and groaning.

Also a couple of other things --
-I assume the big bolt at the bottom of the diff is the drain plug?
-Does the diff drain plug use the same washers as the oil pan drain plug?

Thanks!

 

If it is making noise I would take it to the dealer before I did anything. Maybe they will do nothing, maybe change the lube, maybe fix it, but you will have the report on your service record before it craps out.. they usually do once they start moaning.

If you insist on changing it the manual call for GL5 / GL6. I used Mobil 1 gear oil when I changed mine.

 

Cdelena, at what mileage did you change your differential oil and is there a specific weight to use or is it just Mobile 1 gear oil?

 

I just changed mine at 13,000. Condition was ok, but I heard Mingster's story and figured it couldn't hurt. Honda recommends change every 15k. . I used Mobil 1 gear oil. (dealer recommended) Hope that helps.

I would have dealer check if its making noise. I agree with Cdelena that it would be better documented, just in case.

 

Coincidently, I just changed the differential lube this morning - the car has 12,900 miles. Yes, the large bolt in the center of the jack point on the differential is the drain. The other large bolt on the back side of the casing is the fill/level bolt. Here are some tidbits:

1) The diff drain plug is 24mm and you need to use a socket to access it.
2) The fill bolt is a different, smaller diameter, and it doesn't look like there's enough clearance for a socket, so you'll need an open end or box wrench. I didn't have the correct size for it, so I used a 20 cm (8") adjustable wrench. If you use this type of tool, make SURE that it is a METRIC adjustable wrench . And, seriously folks, be careful not to break any of the cast aluminum fins in the diff.
3) The drain bolt has an aluminum washer and the fill bolt has what looks to be a copper washer. I don't know if either the same size as the oil drain bolt washer, but I think that it's larger.
4) The fill bolt hole is also the level to which you need to add oil. I wanted to use Mobil 1, but couldn't find any, so I used Valvoline SynPower synthetic GL-5 75W-90. Mine drank about 0.85 quarts, so one quart should be morethan enough.
5) Buy one of those inexpensive fluid pumps (a few $$) at your local auto parts store to pump in the diff oil. You'll be glad to have one around when you go to do this procedure.

 

From Helm Manual Section 15-6:

Oil Capacity
0.74 L (0.78 US qt., 0.65 Imp qt) at oil change
0.77 L (0.81 US qt., 0.68 Imp. qt)at overhaul

Recommended Oil
Hypoid Gear Oil
API Classification GL5 or GL6
Viscosity: SAE #90

Use a new washer on the oil plug.

 

I changed mine at about 6000 only because when I changed my transmission oil (trying to reduce the 1 - 2 grind) it was truly so bad I was afraid all the lube was suspect.. it was not, when I changed the diff oil it did not look all that bad. Gear oil will always appear to those not used to it worse than it really is, and everyone finds a coating of fine metal on the magnetic plug which I assume is normal.

Honda calls for 90W GL5 / GL6. Mobil 1 gear lube is a GL5 75W90 lube. Yes, the washer is larger than the engine oil washer, and I think the book recommends changing the oil every year or 15K miles.

As I understand it GL6 lubes are actually more slippery, but that makes them unsuited for many uses so it is very hard to find.

 

As for the washer I'd check with the dealer, but it's a very safe bet they're the same:
1) Both plugs are torqued to 35 lbf-ft
2) No reason to use two sizes functionally
3) Cheapest way to manufactue if hole/plug interface is common (i.e. no tool change during machining).

 

My mistake on the washer.....they are the same for the fill and drain of the differential...not the engine. Mis understood question.