When I went thru my 17A a few years ago I wanted to put new hydraulic track adjusters on it, CAT wanted $1100.00 a side for a D7 with a little digging we found out  D6C. D6D were the same adjuster with the exception of the grease fitting which we could make work with a little tin work for $170.00 a side aftermarket.  With the help of a good fabricator, a good machine shop and a little digging some imagination you can keep those old girls working for a long time and make them as good or better than when they came out. Most people will say they are not worth putting any money into my answer is it’s not what their worth but what they can do for me, that has kept me going probably longer than I would have any other way!  17afarmer

Thank you 17Afarmer. That is the perfect kind of information to put on this board for all time in the future.