engine trouble

[ram15]

The other day my truck started shaking when I hit about 45 and when I got home it looked like I blew a valve cover gasket so I just tightened it back down and it stopped. But yesterday it happened again, could these be related and what could be the cause

 

[SmokedRam]

Maybe a clogged breather?

http://www.rockauto.com/catalog/moreinfo.php?pk=360273

 

[garner]

Sounds like too much pressure is building up. I agree with Adam about the breather. Or the bolts aren't holding like they're supposed to which is causing it to come loose

 

[ram15]

Do you think the shaking could be related to the clogged breather and blown gasket