I know this has been mentioned before but I don't think it has specifically to my vehicle. I have a 95 Honda Odyssey and I was given this information by another Ody owner who lives in New Zealand but bought a used Ody which originally was sold in Japan and has the same engine/tranny as mine. I asked him what his owner's manuals suggested for oil recommendations and he told me the Japanese manual when translated states:
"Honda Genuine Oil (4 Cycle for 4WD)
Ultra MILD (API SG, SAE 10W-30)
Ultra LTD (API SG, SAE 10W-30)
Ultra GOLD SPECIAL (API SG, SAE 10W-30)
Ultra GOLD (API SG, SAE 5W-30)
Oils that are above API SG grade, or oils that carry the API CERTIFICATION mark may also be used.
Use an appropriate level of viscosity for the outside temperature."
He then told me that he has an owner's manual from New Zealand and this is what it states:
"My NZ one is more an international one, so has both Celcius and Farenheit, and it actually says "Always use a fuel-efficient oil that says "API Service SG or SH". This oil is formulated to help your engine use less fuel".
The chart is approx.
45F to 90F 30
10F up beyond 100F 20W-40 . 20W-50
0F up beyond 100F 15W-40 . 15W-50
-10F up beyond 100F 10W-40
-10F to 90F 10W-30
90F down to below -20F 5W-30"
I find it interesting the differences between the U.S., Japan and New Zealand markets. This of course leads me to believe that I can use any of those weights of oil in my Ody as long as I am using them in the specified temperature ranges.