I wouldn't use that heavy of oil. You get 'intra-fluid-friction' that actually makes you loose power because it's harder to move around/thru. Like having a 5gal bucket of mud, trying to mix it with a stick.
If you can, find some Amsoil and use the 0W20 or 30. I've been selling/using it for over 13yrs and it hasn't let me down yet. And usually you can go 3-5x longer before changes.
Honda still recomends motor oil in the manual tranny's right?
Use a 10w30 in there also.
EF-kid.. What does the trans have to do with the oil filter?
I've used the longer filters for the acura V6's that give more volume and no leaks.
What's this about the Rodeo filters?
E