1st, are they 370 or 370G versions? I've used both the 270 & 270G, and I've never seen anything that says either of the series do LTR. There are other kenwoods that cover that, as well as some scanners.
Here is a page that shows SOME of the current and recent HTs that kenwood has sold. The 373 and 380 (among others) do LTR
Just a WILD guess here, but of they are indeed 370s, they could also have a Smartrunk controller installed. Anyway, good luck, it's my bedtime....