There are two options for holding valves--one is an add on unit that attaches to the drive motor and the other is to install a travel control valve with the holding feature built in.
The add-on holding valves should work on any model but it is important when you purchase one that it includes all of the necessary hydraulic tubes or you will have a lot more difficulty installing it.
Installing a new travel control valve involves moving the location of the valve slightly and tweaking the tubes a bit to fit but is not terribly complicated.
The stand alone holding valves generally sell in the $200 range and the travel control valve with the integrating holding valve run $250-300.
The add-on holding valves should work on any model but it is important when you purchase one that it includes all of the necessary hydraulic tubes or you will have a lot more difficulty installing it.
Installing a new travel control valve involves moving the location of the valve slightly and tweaking the tubes a bit to fit but is not terribly complicated.
The stand alone holding valves generally sell in the $200 range and the travel control valve with the integrating holding valve run $250-300.