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Hello. I was wondering about what kind of gear oil to use in my tranny and Diff. I have a 1974 Car with a 1750 motor. Not sure if the tranny is the original though. Can I use REDLINE? and if I can what weight should i buy? As for my Diff, What kind of fluid does it use? I once used the wrong stuff in a BMW LSD and I got weird noises coming from my diff. Thanks!
 

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Any suggestions on where to get the Redline 75W90 NS ? I live in South Carolina and Autozone and Advance Auto Parts don't seem to carry it?
go online to: Red Line Synthetic Gear Oils: RED-58304 - summitracing.com
FYI, I've ran Mobil One in my trans and rear end for over a year with no trouble whatsoever from the lubrication department (come on, my trans needed a bolt put back into it, that was not Mobil Ones fault!).
 

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You can buy Redline 75W90NS from IAP and Centerline.

Go to REdlines website for technical info (dealer info), especially the Syn Gear Oil that is the (NS) and how they make it specific to the needs of our synchros.

Costs about $10/Qt.

TTFN Elio
 

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This is where I buy Red Line (but I don't use it in the Alfa)
do you consider REDLINE to be inferior or maybe, not adequate for an Alfa tranny? I'd like to get as much info as possible.
I prefer non-syn's in my Alfa. I use Spirax in the gearbox and rear end, and a non-syn in the crankcase.
 

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redline fever

I just (100mi.) put redline 75-90 NS in my tranny and the non NS version in the diff. and it seams very good. It won't cure a bad second gear syncro but sure makes the shifting smooth.
 

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What Kipp says may be true, but you might br buying the equivalint to Redline 75W90MTL Gear Oil. For our boxes you need the 75W90NS, this oil has a non slip (hence NS) that makes the synchros spin and not slip.

I used to work for Esso/Exxon.

TTFN Elio
 

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Yeah I don't use this stuff either. I use synthetic in newer alfa's. Synthetic is not a big deal as they do recommend AGIP Sint 2000 which is a blend.

Agip Sint 2000 10W-40 [Agip Synthetic Blend motor oil] - $45.00 : American AGIP, an ENI Company
Spirax is good and does very well. You can use AGIP if you desire for engine oil.
AGIP 20W-50 SUPER XL [Agip Passenger Car Motor Oil] - $32.85 : American AGIP, an ENI Company

Use what the car initially was made for. Synthetic is good stuff and will work fine in a spider. You can pick up what you need directly from AGIP and Spirax is carried at PEP-BOYS.
AGIP is located in PA so it may not be to expensive to ship to you.

Anyways: Oil is 10W-50, or AGIP Sint 2000, 10W-40
gearbox and diff is Spirax 80W/90

Also Castrol is a good oil in 20W-50.

Jason
 

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For our boxes you need the 75W90NS, this oil has a non slip (hence NS) that makes the synchros spin and not slip.
This was a curious statement, could you go into detail about this one?
NS=Non slip, friction modified, for use with rear ends with clutch packs. A synchro spinning freely on a shaft between 1rst and 2nd would not be affected as much by using just motor oil with no friction enhancements as would a synchro spinning on a shaft with a friction enhancement...
I see what would seem like logic, increasing the friction between the spinning main shaft and the synchro itself is spinning between 1rst and 2nd or 3rd to 4th, but at the same time eliminating all the friction to begin with would do the exact same thing as inertia is still alive and well in our transmissions (which makes me wonder how much energy of the synchro is left after double shifting...).
 

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Friction is different than slip (shear).

If you go to Redline's website, their technical writeup will give you background. In essence the synchros have to spin to achieve synchronous speed, if there is too much slip they will not speed up satisfactorily fast. Hence the NS designation, Synthetic gear oils tend to have too much slip.

TTFN Elio
 

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In essence the synchros have to spin to achieve synchronous speed, if there is too much slip they will not speed up satisfactorily fast.
TTFN Elio
That is what I was questioning to begin with. "Synchrounous speed", could you go into detail about that as well? Synchros do not speed up, they slow down, no matter what you use, I'm getting very confused about the terms you are using, I'm not poking fun or otherwise, would just like to sort this out.
 

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This was a curious statement, could you go into detail about this one?
NS=Non slip, friction modified, for use with rear ends with clutch packs.
The Redline naming convention seems a little backwards, but Elio is correct:

75W90NS = Does NOT contain friction modifiers, best for use in Alfa trannies

75W90 = DOES contain friction modifiers, for use in Limited Slip Differentials

Joe
 

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The Redline naming convention seems a little backwards
75W90NS = Does NOT contain friction modifiers, best for use in Alfa trannies

Joe
Well, Mobil One has been working awesome for me in either case, that NS designation does seem a bit backwards. Thanks Joe, you described what I couldn't, no friction modifiers in a NS fluid-yes, definetly backwards!!! Thanks Joe!:)
 
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