July 24th, 2017 by Chris Hemer
Our new SuperSteer quad shock kits for the Ford F53 motorhome chassis are generating a lot of excitement, but also a lot of questions. The most common one we get is, “Why do I need quad shocks?” Well, to understand the answer, first it’s helpful to know a little bit more about the Ford F53 motorhome chassis.
SuperSteer quad shock kit shown with SuperSteer Ultimate Dual Sway Bar kit
At the risk of telling you something you already know, the F53 chassis is built by Ford and is available in a variety of gross vehicle weight ratings (GVWR) from 16,000 pounds all the way up to 26,000 pounds. Though the ratings give motorhome manufacturers more flexibility in the products they build, Ford has no way of knowing how their chassis will be used when it leaves the factory.
The coach that is built on that chassis may be near the GVWR, or may be well below it; it may have a lot of rear overhang, be heavier at one end or the other, or even be heavier on one side than another. Because of these factors, the F53 chassis is like a one size fits all T-shirt–it works on most motorhomes, but is usually not a perfect fit for any of them. Think about it in car terms–can you imagine if there was only one chassis for all the car manufacturers to build on? How could any of them ride or handle to their best potential?
At Henderson’s Line Up and our sister company, SuperSteer parts, we are always looking for ways to improve the ride, handling and safety of motorhomes. Obviously, one big factor in ride and handling is the shock absorbers–so in the late 90’s we started experimenting with the Chevy P32 chassis. We tried Bilsteins, then Konis, but found that they still couldn’t produce the result we wanted. Eventually we decided to try both–one Bilstein and one Koni on each side of the rear suspension. Our logic was, one has different valving than the other, and they will complement each other. It worked, but our customers were having to sacrifice ride quality for better handling. We wanted to improve both. So when the new Koni FSD (frequency selective damper) http://www.koni.com/en-US/Cars/Products/Performance/FSD/ was introduced, we tried using four of them on the front suspension. We found that the two FSDs created an amazing result: The coach rode and handled better, produced less road noise, vibration and porpoising (when the coach continues to bounce after a bump). How can that be? We figured that, by using two pairs, the shocks were able to stay in their higher frequency longer when going over rough pavement, railroad crossings, etc. We thought it might be a fluke, so we tried the rear suspension. By golly, it fixed the ride in the rear as well!
Since the number one complaint we get about the Ford F53 chassis is rough ride and excessive noise, we began working on quad shock kits for the F53 as well. My brother, John our sales director and engineer/fabricator, figured out an easy solution that consists of longer Grade 8 bolts and custom made steel spacers (that vary in width depending on application) that make it possible to mount four shocks on each side. The only exception is the 24,000 and 26,0000 GVWR chassis, which requires a bracket to slightly relocate one left front shock to clear the steering arm and drag link; one left rear shock to clear the larger rear differential on these bigger chassis. The result? Motorhomes on the Ford F53 chassis with our quad shock kit ride quieter with less vibration and a lot less body roll and porpoising. Front and rear quad shocks with brackets runs about $2,000, but man does it transform the motorhome. Call us for a fit list for your specific motorhome.
We’ve got a lot of options for the F53 now, depending on how well you want it to drive including SumoSprings https://www.supersprings.com/products/sumosprings/, front and rear sway bars and more. We’ll blog about these improvements in upcoming posts.