best attachment for ripping out old lawns

we are doing a lot of new sod install work. we have a new holland ls 170 and was wondering whats a good attachment for tearing out old exisiting lawns? a harley rake?? i dunno.. i need some input.. thanks

 

im sure people rent these so we can rent them before we decide to buy.. right?? when i did a search on this topic it seems like everyone uses the rakes on new construction. but what if i have decently thick weedy lawn? thanks

 

Round-up and a roto-tiller, then rake.

 

We have used the harley rake on existing lawns does good , one amazing tool.