Question
Hi, I layed burmuda 419 sod two weeks ago.  We are now seeing a good bit of grabgrass growing in our sod.  Our old lawn was a mixture of burmuda and fescue with a lot of crabgrass mixed in.  We peremerged last march, we completely round up the entire yard about 2 weeks before our sod project. Then before sodding we tilled the entire lawn.  Is this normal for crabgrass to come up so soon and how could i get rid of it.  
Thank you,
Adam

Answer
Something is eluding me here. If you put down clean sod, the crab grass should be coming from below and therefore through the seams of the sod. If this is so, then you need a commercial service to apply the chemical(s) which will reduce the crab grass infestation.
If the crab grass is germinating out of the sod itself, then you might want to address this with the people from whom you bought it.
You may have set yourself up for the problem when you tilled the entire lawn. Tilling promotes seed germination so all the seeds in the ground started sprouting. Had you allowed them to sprout, even encouraged them by watering, a second application of glyphosate would have taken care of much of the weed problem you now have.