They make coolant filters and adapters for all sorts of engines, especially the diesels. i have intended to have one added to our motor home. You know how that goes. Just two months ago had Freightlinenr change the coolant and should have done it then. Doesn't matter if it is a gas engine or diesel on a motorhome or any other vehicle it is a great idea. One time I looked up the cost, when Cat was still servicing their over the road engines in motor homes. Seems like it was around 300.00. Biggest decision is where to mount the base or adapter and substituting hoses to reach it....and of course add in the cost of another coolant change.