New battery now running rough

So I live in North Idaho and replaced my battery because it was going out it was about 8 years old. After I replaced it my truck started running rough down to about 500rpms it was on the verge of dyeing the guys at O'Reilly's hooked up to the new battery and said the alternator was bad the voltage regulator was bad so I replaced it and it runs bit better but still runs rough. It ran fine and didn't have the problem before I changed the battery. Any suggestions on what it could be would really be appreciated. Thank you.

 

check the electrical connections and make sure they are clean of corrosion

 

I checked and cleaned my connection before I put the new battery on.

 

It should smooth out after running a few minutes, once the power connection is lost the computer has to relearn the air/fuel mixtures.

 

Ok I'm gonna take it on A drive to work to tomorrow about 60 miles round-trip see if that does it. Thank you guys for your help.

 

Update she is now running like a champ thanks again.

 

I hate to say it but I think you may have change your alternator unnecessarily.

 

Yea I think so but thats what I get for trusting people at O'Reilly's, well one less thing to worry about.