# Questions about new engine oils and their many varieties

**URL:** <https://boards.straightdope.com/t/questions-about-new-engine-oils-and-their-many-varieties/1015524>\
**Category:** In My Humble Opinion\
**Created:** [March 13, 2025, 12:28pm UTC](https://boards.straightdope.com/t/questions-about-new-engine-oils-and-their-many-varieties/1015524 "2025-03-13T12:28:12Z")\
**Posts on this page:** 1\
**Page:** 3

<div class="post-metadata">

**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\
**Post date:** [March 14, 2025, 6:21pm UTC](https://boards.straightdope.com/t/questions-about-new-engine-oils-and-their-many-varieties/1015524/41 "2025-03-14T18:21:26Z")

</div>

> [@crazyjoe](#):
>
> Do you fill the oil filter with oil prior to installing it? It’s recommended if you can, but if your oil filter is mounted horizontally (or worse, where the gasket is face-down), it’s a royal pain so I skip it.

If (and only if) the filter is vertical, then I’ll go ahead and pre-fill the filter. My reasoning being, “It can’t hurt, and might even help a little.” But if I forget I don’t lose sleep over it. I figure that, if it were important, then all engines would be designed to have vertically-mounted oil filters.

[Previous page](https://boards.straightdope.com/t/questions-about-new-engine-oils-and-their-many-varieties/1015524.md?page=2)