Ok what I see is it seems to do fine until you get into some boost. Did you hit a hill or something to climb? When the boost comes on that's when it looks like the surging starts. So that would make me think it's boost related. The reason I would assume then the it surges is because it's making you MM3 jump up and down which makes the rest jump up and down. What are the rest of the mods on this truck?
My first suggestion would be to lower your main duration in the mm3 x FRP area that the surging is occuring. Looking at your main duration map vs mine, your duration numbers are way higher than mine are.
My duration table:
Attachment 19134
Your duration table:
Attachment 19135
TAKE ALL THIS WITH A GRAIN OF SALT!! I am in no way a professional tuner!! Just throwing out what I see is all.