driving problem

when im driving down the road almost every time at about 50 miles per hour my truck act like its running out of gas, like it is back firing. then i let off the gas and it runs good.im thinking gas filter , may be out of time , but im not verey good with this kind of thing only the basics. any info will be appreciated.

thanks :icon16:

More info would be nice.

yeah more info is really needed, but yes the fuel filter can cause that, same with low fuel pressure.