I am truly disgusted at hostgator's shared server policy. Summery: If you hit a spike of traffic in a 90 seconds interval, your site is going DOWN. So if anyone have suggestion of another host that's reliable please let me know. Here's the full chat log with their support for those that care to read the details. The key parts are in bold:
I've always found HostGator to be one of the best shared hosting providers and know of some rather active sites hosting on their shared plans. I guess you just got caught out at the wrong time. Considered a VPS?
4-5k of visitors daily with vBulletin with VBSeo with shared hosting especially hostgator? You must be kidding ! You need VPS at least. No shared hosting.
I agree with xrvel, there comes a point where you have to upgrade to more resouceful hosting. If you have been at a host any length of time and have been happy, then see if you can do a deal on an upgrade.
I don't have anything amazing to add other than the fact that I've been with HostGator for about 4 years and haven't had this problem. Then again, you probably get a lot more traffic than I do. Time to leave shared hosting?
That is very wierd, I've used HostGator awhile back and they would limit the connections to 15 concurrent so this wouldn't even happen usually.