transmission oil

[sugarbeet]

I'm building a doodlebug out of a I believe to be a 30 0r 31 AA truck set up for duallys. Do I need to use 600w oil in the 4 speed transmission?

[spectria]

I'm building a doodlebug out of a I believe to be a 30 0r 31 AA truck set up for duallys. Do I need to use 600w oil in the 4 speed transmission?

From everything gathered here and in the books, yes.
The straight cut gears are prone to grind without the resistance of the heavy lube.

I would run 80w-90 synthetic in a new transmission with tight clearances, but shifting would require extra care. Also the shift detents, springs and interlocking balls would need to be excellent, IMHO.

[sugarbeet]

Thanks for the information, would a quart be enough to fill it or do I need to order more?

[Reds34]

You will need two quarts. I think it is technically just over two, but I just put two in the transmission for my '34.

Red

[sugarbeet]

Is there a modern version of this 600w or do I have to send away for it?

[tiredtruckrestorer]

The 600W is a ISO grade (International Standard Organization). It is equivalent to a 140 SAE grade (Society of Automotive Engineers) gear viscosity number. I think I may have picked up some straight 140 from Tractor Supply once. Do not use the multi-vis 85/140 or 80/90 that is frequently available. I don't think these transmissions are sealed up good enough to use these lighter gear oils. If you have a Lubriplate dealer in you area, they would have a straight 140 gear oil. You could check online if they have a dealer near you. I use their #SPO-288 which is also compatable with brass/bronze worm-drive gears.

Keith

[sugarbeet]

Thanks Keith, I will check this out, got to go to Tractor Supply this morning, good information.

[BigAl]

There is a home brew out there on the web that includes melting bearing grease, STP and gear oil. Do a search. The original stuff smells like death warmed over. I also have bought a modern equiv a few years ago from a RI distributor in a 5 gallon pail.

[Stakebed]

There is a home brew out there on the web that includes melting bearing grease, STP and gear oil. Do a search. The original stuff smells like death warmed over. I also have bought a modern equiv a few years ago from a RI distributor in a 5 gallon pail.

haha as one who just tore apart thier worm drive: smells like children's purple cough medicine thats been set on fire...good to know about the 145 weight

[spdway1]

Did anyone find 140# at a store yet? What one?

[spectria]

Did anyone find 140# at a store yet? What one?

http://shop.advanceautoparts.com/webapp ... _7070502-p

[spdway1]

Did anyone find 140# at a store yet? What one?

http://shop.advanceautoparts.com/webapp ... _7070502-p

Thank you.