My accord does not say anything about any oil other than 5W20. Is anyone using 5W30 instead or do you think either is really better.

Is it under warranty? If so, se the 5W-20 specified.

If not, use 5W-30 or 5W-20, it doesn't really matter.....

It doesn't matter.

What year is your Accord ?

It is a 2008, about to run out of warranty.

You can use 5w30 if you want. It won't break anything. However they will run forever on anything.

Hondas love the thin stuff. Stay with 5W20. Motorcraft 5W20 is really good.

I have had a new Honda since 1980...or an Accura...

Presently Honda 2010 Accord V-6 iVtec/VCM SE/LX NAV.

You will not notice a difference in performance using either 5W-20 or 5W-30.

Have a 2008 CRV too 4-cyl...use Quaker State semi-syn 5w-20...OCM pops up about 7,000 miles...have not even a remote thought of changing.

...now I do know that if you use 0W-30 GC or a 0W-40...the car engine needs to warm up and get to temperature...and signals that the engine does like a thinner oil..

..why fight city hall...5W-20,,,

I use 30 weight in summer and 20 weight in winter in my 2007 Accord 2.4.

Either grade will work just fine, and you won't notice the difference in any way.
If you go to a 15W-50, you might notice some loss of high rpm repsonse.

9.1 or 9.7 cSt? 6% difference in viscosity? Use what ever gives you a warm fuzzy feeling.

for warranty, 5w-20. But think, in Australia and the Eu they spec 40wt and some 50wts in aus for the same engines. Kinda makes me think how bogged down we are in our CAFE standards. c'mon a 1mpg drop at max? That's worth it for extra high-rpm protection.

The interesting thing about CAFE is that the US market has forced oil manufacturers to make amazing light viscosity oils. Possbily created a greater demand for synthetic oils. Smog control...clean air...it was needed...we now have 600 HP engines...that are clean...ZR-1. So it can be done...

anyways...maybe the question ought be...5W-20 conventional or 5W-20 synthetic?

...if you live at the redline...race...very hot climate...it's very cold...then you have a reason to switch...do you have a reason?

...speculation is not a reason...

It's more than that though, the startup viscosity of most 5w20s is way more favorable than that of most 5w30s. And considering the fact that a lot of 5w30s end up thinning out to a 20 weight anyhow, you might as well just start out with 5w20 to begin with (or better yet, 0w20)

I once said there wasn't a difference and I was burned at the stake by the HTHS posse.

I'd stick with the 5W20. What problem are you trying to fix?