What fluid does the tranny take on a 4104 ?

[Gerry4104]

What do you guys recomend... TIA

[roadrunnertex]

Same oil as the engine.
Delo 100 40 wt

[Gerry4104]

I know i could look it up, but as long as i'm here what are the capacitys for the engine and the tranny....

TIA

[zubzub]

the '04 uses a special mineral oil (motorcycle 50W racing oil has same spec)  someone will chime in with the proper info.  It's in the book, just trying to use my memory.

[gus]

The book says Aviation Grade 50W but I see no reason 40W won't work. This aviation grade in the book is actually mineral oil which all aircraft once used but it is now called "break-in oil" for newly overhauled aircraft engines. It is expensive but I had some left over that I got by mistake.

Just don't ever use 90W, happened to me once at a bus place that should have known better!

[bevans6]

I use synthetic 50W transmission (not gear) oil, in the hopes of easier shifting into first gear.  I agree that 40W engine oil is fine.

Brian

[gus]

The reason these old bus and truck trans use light oil is they have oil pumps built into the input shafts - my old '50s GMC big trucks use the same stuff.

[WEC4104]

Some folks have experienced smoother shifting using the synthetics, however your transmission seals have to be in good shape.  Switching to synthetic has created leaks in trans that were "tight" with dino stuff.

[gus]

Synthetics also break loose a lot of sludge and crud that has stayed in place for years.