Gear Oil Change out

[BryanL]

I am new to the Alfa community having recently purchased an 87 Quad. I've been reading the threads concerning the 2nd gear syncro.
I occassionally experience the grinding problem and I think I want to change the gear lube to the recommended Redline 75W90NS GL-5 Gear Oil based on the merits of the previous discussions. I am not sure what is in there now.
I've not climbed under the car yet but I am wondering how to change out the gear oil.
I assume there is a drain plug and a fill plug on the gearbox?
I have to order the oil from a local Redline dealer as he does not stock that product # 58304. What is the fill capacity in quarts?
I assume you drain the gearbox then refill until it "leaks" from the fill plug? Is this correct?
Any other information I should be aware of before I attempt this change out?
Thanks for any information supplied.

[spiderserie4]

yes you seem to have got it right.
First make sure you can loosen the fill plug (if you drain it first and then find you cannot open the fill plug, you have a gearbox without oil, so can't even drive to a local mechanic.......for example!)
The drain plug should have a new copper washer before you close it up.
You will need a 12mm hex for the filler plug and a 22mm socket for the drain plug (well that is what I have on my 1990 S4 spider....guess they are the same)
The capacity is basically 1.85 litres, a touch under 2 quarts (as Redline comes in quarts, that is handy!)
Ideally, as you do not know what oil is in there, you should actually use a cheap oil to swish out the old stuff (like an SAE 40 "straight grade" engine oil, which is not dear) for a few hundred miles, then put the expensive Redline NS in....up to you. I did!
It makes life easier to get an oil syringe with about a foots length of clear hose on the end, to pump in the gearbox oil.
I bought something like this that holds half a litre........makes the job so much easier...redline is fairly thin oil and goes in a breeze with this type of syringe.

EDIT: yes fill it till it stops leaking from the fill plug - car dead level, obviously

[sloboy89]

Quote:

Originally Posted by spiderserie4 You will need a 12mm hex for the filler plug and a 22mm socket for the drain plug (well that is what I have on my 1990 S4 spider....guess they are the same)

[spiderserie4]

that is a good point by Sloboy89 about the magnetised drain plug.......if for some reason you find your g/box does not have a magnetised drain plug (lazy mechanic or PO chucked it away, or something), I would absolutely invest the 10 bucks or so and get one!

[Elio Comello]

I assume you will do the Differential as well?

Do NOT use the Reline 75W90NS in the Diff

Shell Rotella 80W90 Dino oil works good or the Redline 75W90 Differential oil.

Ciao for now...Elio

[BryanL]

Great ideas SS4 and SB89. Thanks for the information.
Elio....my plan is to do just as you suggested...
Thanks Guys...........

[Alfar7]

Actually the correct lube for both the trans AND LSD differential IS 75-90NS Redline. The other is way too thin and without needed additives.

[BryanL]

Thanks ALFAR7....I'll do a little more research.......

[Gubi]

Augh. Ten years on and people are still getting this wrong.

Redline 75W90 has the limited slip additives. It is correct for the differential and should NEVER go in the transmission.

Redline 75W90NS does not have the limited slip additives. It is correct for the transmission. It won't do any damage in the differential, though it might cause LSD chatter noise. It will increase LSD lockup which is why some people use it in the diff.

Please see the tech article on gear oil on the Redline site. It explains all this stuff.

[mknoll1]

for what it is worth I stopped by DiFatta Brothers who specializes in these cars and they told me to use AMSoil severe gear 75w-90. It was $12.50 a quart and you need 3-4 to do both the trans and the diff. Manual says 1.65 liters for trans and 1.25 liters for the diff but I spilled some.

[Giovanni2000]

so what size tools are the three plugs(fill, drain & diff) for an 82 spider? I seem to have received conflicting sizes.

[Goal660]

I used shell spirax in the gear box and castrol 80w 90 in the diff with LSD additive. It's amazing how smooth the drive is with fresh fluid!

[Alfar7]

75-90NS is the correct lube for both!

From Redlines site:

Quote:

Since most GL-5 gear oils for differentials are too slippery for manual transmissions, Red Line offers these products that ensure proper shifting while providing ultimate wear protection Appropriate coefficient of friction for most manual transmission synchronizers (other's synthetic gear oils are often too slippery for proper synchro engagement) Red Line offers lubricants to pinpoint nearly every transmission application MTL, MT-85 & MT-90 are not for use in differentials with hypoid gears Excellent gear and synchro protection, balanced slipperiness for easier shifting in cold climates

[David in NC]

I just had both changed at Apex Vintage in Raleigh, Alfa specialists.
They used 75/90NS in trans, and regular 75/90 in diff.
Same as I had previously read on alfabb.

[David in NC]

Interesting that alfabb has variably quoted 2.3 qts, 1.65 liter (=1.75 qts) and 1.85 liters (=1.95 qts) as tranny capacity (S4). I bought 3 qts and they used exactly 2. Suspect 1.85 liters is the right answer, and only need to purchase 2 qts.