600 weight oil ?

ivoryjohn

Senior Member
I have a transmission that is down in oil quite a bit due to an engine swap. I also have a new rebuild on a two tooth steering box but it doesn't have any oil in it yet. Both of these require 600 weight oil and I have about a third of a quart to use to fill both. Probably not enough to fill up the transmission to the bottom of the fill hole.

I want to stay with what is prescribed and that is 600 weight but I also don't want to wait for an order to come in next week via UPS. I'm itching to get rolling with breaking in my new engine and I only have to button up a thing or two and crank it up.......I hope.

What is a substitute oil for 600 weight I can buy locally to put in the steering? I want to pour the third quart I have into the transmission because there is already some 600 in it and it just needs brought up to level.

I've heard STP is okay for the steering gear box or should I just wait and use the correct oil when it arrives.
 
Thanks for the correction. I fell to the apparent common misconception that "w" meant weight as in 30w being called 30 weight.

It won't cause a problem oils in the transmission to mix the oils?
 
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One: are you going to top it off now, drive it until you get "600 weight" and then drain and fill both the steering box and the transmission. If so you could probably use any heavy weight oil for a short period of time.

Two: if you are going to top if off now and not do anything in the future, but drive it. If so you could probably use any heavy weight oil FOREVER.

If you read all the threads about "600 weight" oil versus other oils on this forum, you will find 48 different opinions.

STP satisfies a number of people on the forum, but others claim it will destroy your entire MODEL A from the inside out.

I would be willing to bet that chainsaw bar oil would probably work in the transmission as well as anything else. But it would probably be a little thin for the steering box and would leak more than some of the thicker oils.

If you live in an area with a number of auto parts stores or an oil dealer, you might be able to find one of the modern oils mentioned in the forums that are equivalent to what they use to call "600 weight", do a search a number of them are mentioned in this forum. If so that would solve your problem of having to wait for shipping.
 
600w is a type of oil still sold by Mobil. It is also called steam cylinder oil.

"The Mobil Cylinder Oil brand of lubricants represents the earliest lubricant product marketed by our Corporation's predecessor companies. 600W Cylinder Oil was produced by the Vacuum Oil Company in the second half of the 19th century and was a breakthrough product of its time. Continual upgrading and application of the latest base oil and additive technology has maintained this product series as a leader in its application areas. While steam cylinder applications are now less common, the reputation of Mobil Cylinder Oils in worm gear applications remains unmatched among mineral-based products."

Do not read into this that I'm saying you have to use it. This is just for historical information.
 
Fill your rebuilt steering box with your 600W. top off your transmission with 250W. Don't worry about mixing the oils. When the 600w comes in next week drain out the transmission and refill with fresh 600w.
 
This gear oil issue is sort of a common subject so I threw together stuff as I understand it. Not very technical and not telling what you must have just some background on some whys.

It may not be 100% correct, please email me any corrections.

Gear Oil
 
A store catering to hot rodders might just have some Redline 250 in stock. Another choice is Lucas synthetic racing gear oil, 250 wt.

http://www.lucasoil.com/products/display_products.sd?iid=343&catid=21&loc=show

you can also add 50% Lucas oil stabilizer to rear end oil. It seems to be in every store I go into. They recommend 25% in transmissions, but those are modern helical gears. A Model A transmission would probably tolerate 50% easily. The stuff is as thick as 600w.

I prefer Shell Omala 680, but these alternatives are usually more readily available.
 
Thanks for the correction. I fell to the apparent common misconception that "w" meant weight as in 30w being called 30 weight.
...

Actually, if you check the labels, you will see there's no such thing as 30w oil either; what we would call "straight 30 weight" oil is labeled SAE 30.

The "w" that does appear in multiviscosity oil labels, such as SAE 10w-30, stands for "winter", not weight.

It's just so darned handy to use "weight" as a spoken proxy for "viscosity."

Steve
 
Timothy Kelly, pretty much said it all and I agree. I will just add that the steering box doesn't have a drain plug.
 
This gear oil issue is sort of a common subject so I threw together stuff as I understand it. Not very technical and not telling what you must have just some background on some whys.

It may not be 100% correct, please email me any corrections.

Gear Oil


The Mobilgear 636 is discontinued and is now: Mobilgear 600 XP 680
 
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