Help with oil for dodge challenger 2009 5.7 auto MDS system

[Mexican cuties]

Hi hand book says use 5w 20 for the MDS system, ours had timing chain recall and dealer told us they put in 10 w 40, but now they are saying for an oil change they recommend 0w 40 so confused, want to go with what hand book says but any one know different

Many thanks

[Mexican cuties]

Thanks Mike, we love a man who knows his lubes, and we will stick to what the manual says

[Mexican cuties]

Thanks, jinxy how's things