Before you start reading through all this, I need to state that this modification applies primarily to Phoenix Cruiser models 2100 and 2350 which have exceptionally light front ends. Get your rig weighed empty and also during a trip to determine if this modification is right for you.
Our 2007 E350/PC-2350 with no slide out always sat a little front/high, tail/low, most noticeable when on trips but even when empty sitting at home. Also, the ride up front has always been more harsh than I thought it should be. I looked into the specs of our 2007 E350 to learn that it is built with the same front coil springs as an E450. Given our load distribution and axle weight numbers both when loaded and empty, it seemed logical to replace the front coil springs with lower rated ones that are more appropriate for the weight they support.
Here is the weight distribution of our 2007 PC-2350 with no slide out. It was quite interesting that our front axle weighs 3160 pounds when the rig is empty with nobody sitting in the front seats. During our heaviest trip, the front axle weighed 3260 (only 100 pounds more) with the two of us sitting in the front seats. The weight behind the rear axle is reducing the weight on the front axle, acting like a teeter-totter.
Here are the springs I installed, made by Moog, sold by Rock Auto Parts. I also bought the Moog insulators shown from a local auto parts store, assuming my original ones were needing replacement. To my surprise, my original insulators are made of polymer, much more durable than the softer rubber Moog insulators, so I returned the new ones to the store. I rotated my original insulators 180 degrees so there was a fresh surface for the new springs to rest on.
Here is an original and a new lower-rated spring side by side. Note how the new springs have the coils closer together in the upper area. Instructions that came with the new springs stated to place the closer-spaced coils "up". I measured the material thickness of each, the new ones measure 0.02" less.
It took me about 1.25 hours to replace the first spring and a half hour to replace the second one because I then knew the tools and the tricks to speed up the process.
Once finished and cleaned up, I drove the rig to the auto parts store to return the rubber spring insulators. I drove over a number of road imperfections, sewer covers, and even some train tracks. It was a good test. The best way to describe the change is like this. Before, when going over imperfections, it was a bang/bang. After the change in springs, it is a thump/bang. I was very pleased with the results. Admittedly there were some serious road imperfections (like the train tracks) when the bang/bang still happened. But for the majority of road imperfections, the change is significant.
A few days after changing springs, we went on a weekend get-away where I was able to better evaluate the change. I drove over 200 miles on interstate highways, state roads, farm roads, and city streets. Our rig was loaded up with full fresh water, gear, food, etc and 3 adults. I am even more pleased with the results than I was during the test drive.
I do need to get a front wheel alignment after the change in front springs, but 13 years and 38,000 miles later, it's time anyway. I took pictures of the tires to compare their stance.
Before (You can see the right tire is slightly in toward the bottom, looking pigeon-toed.)
After (As expected, that same tire is now slightly outward toward the bottom. The same applies to the other front tire but you can't see it because it's in the shadows.)
Here are other "before and after" pictures for comparison. The front of the rig now sits 1-1/4" lower which I am very pleased.
AfterADDING THIS SUPPLIMENT THE FOLLOWING SPRING, MAY 2021
Finally, our first serious trip coming soon. In preparation, I replaced our six 14 year old tires, upgraded 4 of the 6 wheels to Alcoa alloys, and got a front wheel alignment which didn't happen without it's own saga....but turned out fine in the end.
My old shop Champion Frame Align in Elgin, IL permanently closed so I went to the competition that put them out of business, Cassidy Tire in East Dundee, IL. They primarily service trucks of all kinds with special attention towards tractor trailer trucks with tires and wheel alignments. They also service motorhomes. They have 4 full-length bays and one 1/2 bay located behind the office.
For the curious..........
They clamp on wireless alignment contraptions that self-level. They clamp on similarly to a wheel weight in 4 places around the rim.
Using a special floor devise, they push the rig so that the front tires rest on the round disks that float for resistance-free steering wheel turning.
The first wheel alignment resulted in a strong pull to the left. Read on why. They sent me home and called me back after they had their equipment recalibrated which resulted in a pull half as bad, also to the left. Read on why. They sent me home again, this time advising me to have a mechanic look at the steering gear box or something else.
This compares the initial visit to the final results. The upper chart with "red" is what I introduced when changing to softer front coil springs. The final results are the lower section. I watched the guy work and there is a lot of inherent slop. He touches something to tighten it after a tweak and it drifts significantly off the mark. So he has to "anticipate" where it will rest after tightening. Also when making one setting better, it makes the other setting worse, so everything is a compromise between caster and camber.
What I learned watching, a wheel alignment cannot be accomplished when the motorhome is new because Ford installs centered bushings. The last picture in this post is of my shop manual which mentions this at the bottom. Being centered eliminates the ability to adjust caster and camber.
Offset bushings are a requirement to change settings. Here is one of mine. It is mounted on top of the steering knuckle, influencing the position of the upper ball joint. If you replace an upper ball joint, make sure to mark the position of the bushing or you will surely need a wheel alignment.
Back home, before running to a shop to investigate the "Pull To Left", I decided to place the front lower control arms on jack stands so I could freely turn the steering wheel left and right to investigate the cause for the "Pull To Left". Watching the steering wheel go back to left of center on its own.....IT HIT ME
.....the heavy duty Safe-T-Plus steering stabilizer I had installed was causing the "Pull". I then adjusted it so it would hold the steering wheel straight rather than to the left, and all is well. I am Very happy! I called the shop and told them the cause for the pull. They "Got It".
Here are two pictures of my aftermarket heavy duty Safe-T-Plus steering stabilizer. The left end is attached with two "U" bolts to the steering linkage. Loosen them, center your steering wheel, retighten, and it's done. Being the fussy guy that I am, I test drove the rig and tweaked it twice for "PERFECTION On Center" when driving.
With the change to softer front springs, alloy wheels, new Michelin Agilis CrossClimate tires, and the front wheel alignment, our Phoenix Cruiser 2350 is riding better than ever before. I can't wait for our next trip.
Here is the page in my massive 2007 E-Series Ford Shop Manual. In the upper-left corner is what Ford says the setting should be. The computer alignment machine matched these "optimal" settings before the alignment officially began. If the alignment shop were perfectionists, and I had exceptionally deep pockets, they would have changed bushings a couple of times to tighten-up the tolerances.
This is probably way more about wheel alignments than most people care to know.
So in conclusion, here is the stance of our rig after everything was done from changing front coil springs, 6 new tires, new Alcoa wheels, and a front wheel alignment. Also during the taking of this picture, my 35 gallon fresh water tank (located against the rear wall) is full, and all my heavy towing hardware is in the rear storage compartment to simulate "trip load" conditions. The slight rear end sag is gone, the rig handles better, and the quality of the ride is improved for us sitting in the front seats. Our PC appreciates the softer ride as well with reduced thrashing when being driven over road imperfections.ADDING SEPTEMBER 2021, Our First Serious Cross Country Evaluation
We headed out from the Chicago area to Glacier National Park Montana, hitting places along the way. This was my first serious evaluation with consideration to our trip-load and tow vehicle. I found myself once again adjusting the Safe-T-Plus for our PC to track dead straight. Once made perfect, I noticed a slight increase in steering floating. It's not much but is noticed. It explains why for many years prior, there was a slight pull to the right, assumed to be an intentional setting many years ago by my old shop to address that sensation.
I observed something surprising with the Safe-T-Plus. When laying on the ground watching the steering linkage move, while Irene turned the wheel gently left/right, I noticed a gentle pivoting motion of it's long mounting bracket. The leverage of the Safe-T-Plus bracket slightly bends the E350 frame which I believe is the source of that floating feel. This leaves me to think the thicker E450 frame will flex less and therefore float less.
I weighed the rig on this trip and found it's weight and weight distribution very similar to previous trips. Referencing the Michelin chart for our new tires, our front tires required 40 PSI and rears 60 PSI, but I put 50 psi up front and 60 psi in the rear. I added 10 extra up front only because 40 sounded too little. The reduction in tire pressure improved driving/riding comfort. Next trip I will try 45 PSI up front and see if it helps address that slight floating action in the steering.
I have a ScanGauge-II mounted which indicated average fuel economy fairly consistent just over 10 mpg cruising at 60 mph on the open road. We lowered our cruising speed from 67/68 to 60 on our return trip to avoid loud engine noise from down-shifting on every incline. I also noticed a reduction in steering floating, additional incentive to slow down. At 60, everyone passed us which was fine, and I was more relaxed and drove for much longer periods. I could burn through nearly a half tank of fuel between stops.
It was interesting to see the same rigs pass us by many times, indicating they were stopping much more frequently than I was leaving me to wonder who was truly making better time. When any Mercedes chassis motorhome passed us, I could hear it's turbo singing quite loudly, a sign of being pushed hard.