transmission fluid

[Jim Anderson]

The shift on my Series V Alpine is getting a bit stiff. When I bought it five years ago,there was a serious leak and I was told to replenish the lubricrant once a month and everything would be ok. I had the leak repaired and now the gear shift is getting stiff again and I can’t remember what I used to put in.
The Rootes Manual suggests something called “Shell Super Oil.” What the XXX is that?
John Logan says it would be ok to put in 80 wgt oil. since it goes to the bottom but looking at the Rootes Manual, there seems to be a pump involved.
So, what do I put in?
Jim Anderson

[jumpinjan]

Go to your Parts store and get about 3 quarts of Castrol HD30 oil. Drain everything out and replace with the Castrol. 80wt “gear” oil, like the motorcycle transmission oils (not rear axle hypoid oil) is fine too. We all use the castrol oil in the transmission and for a new engine break-in oil.

[Tom and Joanne Ehrhart]

I agree with 30 HD oil…………. But 80WT, NO WAY JOSE. STOP-DANGER DO NOT DO IT. The viscosity of 80 WT inhibits the free spinning of gears creating to much of a drag for the syncros to overcome. Sure the driver can “jam” a gear but it overstresses the shift forks and syncros causing premature wear or even breakage. In cold weather shifting gears may be near impossible. I just went through this exercise with an Alpine this spring. Ask, Anthony DiBasttia what it is like.

BTW. The max viscosity you can use with an OD is 40WT. Higher viscosity prevents the sun gears from getting adequate lubrication. The end result is gears turning blue from excess heat and self destruction.

[jumpinjan]

Tom,
Have you ever used (observed) 80wt motorcycle (2-stroke, off-road) transmission “gear” oil. It’s viscosity is just like 30wt engine oil, but has better gear face protection, plus it’s designed to work with clutch friction plates, so it’s very compatible with the overdrives. Engine oils & “gear” oils have different rating scales. Maybe you have the rear axle oil (hypoid gear oil) on your mind. I have found many trannys where the previous owner used hypoid oil, even in overdrives.
Tom, look at this chart that I lifted off the web page:
http://www.repairfaq.org/filipg/AUTO/F_oil_facts.html
___________________________________________________________
| |
| SAE Gear Viscosity Number |
| ________________________________________________________ |
| |75W |80W |85W| 90 | 140 | |
| |____|_____|___|______________|________________________| |
| |
| SAE Crank Case Viscosity Number |
| ____________________________ |
| |10| 20 | 30 | 40 | 50 | |
| |__|_____|____|_____|______| |
______________________________________________________________
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
viscosity cSt @ 100 degrees C

(maybe just go there), as you can see SAE has set up two different ranges for gear & crankcase viscosity numbers. I hope this helps clearify what I was recommending.
Jan

[Tom and Joanne Ehrhart]

Your are correct, I went off the deep end and was thinking of rear end oil. Guess I didn’t read your comments clearly. Speed reading does that.

And I agree that rear end oil can work in the OD. However. its thickness precludes proper sun gear “bearing” lubrication and “WILL” eventually cause bearing failure. Ok, so someone who is a casual user of an OD may get away with it but extended OD use like interstate driving will eventually get the bearings in trouble.

I do not recommend rearend oil use in trans or OD….period. I’ve seen the damage. It may be a band-aid for an owner but it is just that, a Band-aid to solve another problem that is then aggravated by use of the Band-aid.

[Bob and Jean Webb]

Jan/Tiger Tom,
Before you put any Gear Oil in a transmission, make sure you know
what additives are in the oil. If it is a conventional gear oil, it contains sulfur/phosphorus compounds. These additives react with yellow metals:
synchos, etc. Corrosion starts on contact and can not be stopped. Gear oil contains these extreme pressure additives plus other additives intended for final drive units. Manufacturers of heavy truck trans. still
recommend the use of motor oils unless you use a synthetic trans oil.

Coming from many years experience as a oil company rep. , I’ve
seen a lot of things tried. Stick with what the manufacturer recommends.

Bob Webb

[jumpinjan]

Bob,
The sulfur/phosphorus compounds are expected to be found in “Hypoid” gear oil. Yes, do no use this in transmissions that have yellow metal (brass and so on). The gear oils, that I mentioned, probably don’t have any of this, because they don’t really need the “extreme-pressure” additives.

[barry-knight]

All petroleum based lubricants contain sulfur, the only question is how much. If you don’t want any sulfur, the only choice is a full synthetic.

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