I got my rear differential cover from 4xguard a few months back and took a few photos but had not yet put them here on my garage. Here is my set up. I had the front and rear diffs oil changed right after since it was due. I had no issues but wanted to wait for that service just incase. The deal seemed to have no issue with the service since the guard has the hole for the oil plug and they just popped it out and sucked the oil out and replaced through that hole.They never said anything about it being an issue.