A common question is, "If I install a set of GoWesty lifting springs, do I need a longer shock absorber to go with them?" The answer is NO. In fact, it would be unwise to install a longer shock absorber without making other necessary changes to the suspension design.
Like most vehicles, the shock absorber on a Vanagon limits the amount the suspension can extend (down-travel) in both the front and rear. The amount the suspension can compress (up-travel) is limited by collision of the shock absorber body against a rubber bump stop up front, and in the rear by the collision of the suspension swing arm and a rubber bump stop also mounted to the body. The distance traveled between these two extremes is defined as total travel. For the suspension to articulate freely, the shock absorber must be able to compress with room to spare, so that it does not bind and limit up-travel. A longer shock absorber may not be able to collapse to a short enough dimension, which could cause major problems when the suspension needs to fully compress. That is the first and most obvious reason NOT to simply install a longer shock.
The down-travel on all years of 2WD Vanagons is the same. The down-travel on all 4WD Vanagon models is the same, and is about 2" more than the 2WD. This is because VW used the same shock absorber (length, type, manufacturer) on all 2WD vehicles—and all 4WD vehicles were fitted with the same shock absorber, as well (although it was different from the 2WD one!). This is noteworthy, because VW used many different length springs and produced the Vanagon in varying static ride heights.
Take the 2WD Carat model, for example. It came outfitted with shorter springs. Compared to a GL model, it sits about 2" lower. However, both the Carat and the GL got exactly the same 2WD-type shocks. Same with 4WD Syncros—the hard-top GL model and the pop-top full camper had completely different springs and did not sit at the same height... yet they were both fitted with exactly the same 4WD-type shocks.
Installing a set of our lifting springs will make your vehicle sit higher, which necessarily means that you have "used up" some of your down-travel to gain ground clearance. However, the amount of down-travel lost is gained in increased up-travel. You are simply trading one for the other (and it is a necessary trade-off). Total travel is not affected—which is a good thing, because the suspension system was designed for a specific amount of total travel. All of the components that make up the suspension are designed to accommodate this specific total travel.
Our GoWesty/Fox shock for 4WD with remote reservoir allows for 1" more down-travel of the suspension all around. However, these are not just longer shocks. These shocks are a special super high-performance mono-tube design with remote reservoirs. The original shock design is an antiquated duel-tube emulsion design, which limited VW to the travel that exists standard on all Syncro models. The more advanced Fox design makes it possible to get more down-travel while maintaining the same up-travel, and the remote reservoirs are there to accommodate the extra oil needed for proper function. Additionally, achieving this extra inch of total travel requires a specially-designed upper ball joint spacer up front. The rear suspension is not as sensitive to the extra travel as the front, but we recommend upgrading both the axles and the trailing arms to accommodate the increase in total travel. With careful analysis and engineering, we were able to create modifications that push the design to its absolute limit and improve off-road performance substantially. The increased total travel is not accomplished by simply bolting on a longer shock, and it is NOT a requirement for installing taller springs.