Originally Posted by
JDNSW
It all depends on the type of driving you do. I would rate it only as 'necessary' if you plan on exceeding the manufacturer's maximum wading depth by a substantial amount. But if you are operating in very dusty conditions, especially on unsealed roads with a lot of traffic, I would rate it as 'advisable' rather than necessary (allows the filter service interval to be safely higher than would otherwise be the case - in some situations daily servicing should be done!).
In my view the majority of snorkels fitted to four wheel drives are not necessary or even advisable.
John