Gas prices have bounced all over the place lately, so knowing the cheapest time to fill up has been an inexact science at best.

But analysts say that regardless of the national trends, there's one time every week when you'll probably get the most for your money: Wednesday morning.

Seems that in the wee hours of hump-day, station owners and managers check out the local competition and adjust their prices accordingly, typically between 10 a.m. and noon. So gas may be cheaper at 8 a.m. than it is just a few hours later.

In addition, prices will often tick upwards on Thursday and Friday as people get ready for weekend travel and demand spikes, especially on holiday weekends.

All that aside, what can you do to ensure the gas you buy lasts as long as possible? Experts recommend avoiding needless idling, keeping your tires properly inflated, and getting rid of unnecessary items that add weight to your car -- even a simple rooftop carrier can increase fuel consumption by as much as 15 percent.

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