Well, no verb is in a noun class, but the noun "shauri" does seem to be in the ji/ma class, according to the Institute of Kiswahili Research dictionary (http://www.elimuyetu.co.tz/subjects/arts/swa-eng/s.html) and the Wiktionary reference from DiegoJaviUnlam above.
"Kutoa shauri" sounds like a reasonable alternative to "kushauri". That would be "to offer advice", if I understand it right.
Haha, now I have to look up gerund to try and figure out what you're on about - not that I don't appreciate these errudite contributions, I totally do, it helps motivate me to gradually nudge my grammatical understanding beyond noun, adjective and verb, the three of which are my limit generally!
Sorry, jo2dSY! In English, the gerund is when the "-ing" form of the verb is used as a noun.
Noun : "I like fish" (I like these animals.)
Verb : "I am fish
ing" (I am catching fish right now - present continuous.)
Gerund : "I like fish
ing" (I like the activity of catching fish, but I am not doing it right now. I am referring to the sport itself, so it acts like a noun, similar to "I like soccer".)
In this Swahili example,
"shauri/mashauri" is a noun in noun class 5/6 (ji/ma).
"kushauri" is a verb in the infintive (to advise).
"kushauri" is the same verb used as a noun (the activity of advising), which makes it a gerund, and Swahili puts those in a separate noun class.