Technical Process for adding oil to Hydromatic transmission

Harv, I'm guessing that it isn't that common. A single source found so far and everyone else seems to have superseded it with modern stuff. I have no idea if the Whale Oil part is true, but that was common in the first half of the 20th century. The SDS may have something they would rather not be published online, if it's a trade secret or something else.

 

Whale oil is an anti-corrosion additive. There's other modern stuff that does the same job. Modern hydraulic oils for outdoor applications is slightly hydroscopic (to deal with condensation and case vents eating humid air) so that doubly solves the problem.

Start here


All this guy's content is real good BTW

 

Hydrostatic drive oil, for big Allison and Caterpillar transmissions. Designed for this application with the suitable anti froth additives required for oil in a windage tray.

It's the correct 20W and so far has been very good. Tractor Supply.
Alternatives are available but basically search for hydrostatic drive oil in 20W.

Phil

 

And yes, completely missed the beginning of this thread.
The torus has a square drain bung which will undoubtedly be at the top when you stop the engine. Ignition off, rotate the flywheel round with a prybar on the starter ring (don't use the torus bolts) and undo. Regular thread on the bung. It'll be tight. Be ready to catch ~5 qts if the engine has been run in the previous hour.
If contaminants are suspected, recommended to drop the lower transmission pan because the drain plug location doesn't allow the last pint or so to drain out.

As soon as the torus is empty, refit the bung and torque it to spec.

90W gear oil is a touch heavy- shouldn't do much harm to the cork clutches but it can cause the adhesive to let go. Chunky debris in the bottom of the pan will tell you. A small amount (half a teaspoon's worth or so) of fine black dusty-gritty is normal wear and not cause for concern.

Refilling is as described. 6-8 quarts, start engine for 10 seconds, stop then refill until you get to MIN on the dipstick.
Chock the wheels, apply the parking brake and put the car in gear (I put mine in Reverse because it is the most aggressive on the pump and system in most Hydramatic models) then top up the level at idle to FULL on the dipstick. Being on level ground is important because the dipstick is all the way off to the side.

Rinse the dipstick top cap filter mesh with diesel/kerosene/gasoline, thoroughly dry and refit.

Phil

 

Theory is GM trannys modulated shifts with 'slippery' fluid {Dexron) and Ford used 'sticky' fluid (type F) and modulated shifts with smaller fluid passages. Thus theory was use type F fluid in Hydros, get firmer, quicker shifts. Use Dexron fluid in a Ford get a burned up tranny! If you see a graph of coefficient of friction for the fluids vs. rotational speed of clutches, Dexron coefficient goes down as speed slows, type F goes up. Old B&M Trick Shift performance fluid used in all trannys had almost the same coefficient performance as Type F.

Moral; don't use 90W gear oil in a Hydro!!

 

I was wondering where you two were at.

 

That makes me wonder how type F would perform in simple industrial gearboxes and reversers that don't do a lot of shifting but need grabbing power.