Just got back from a 4,000 mile plus journey to the great northeast - had a great trip and for the most part a pretty uneventful RV time.I have a '93 29ft Class C on a Ford E350 chassis with the 460 motor. Pulled my 2014 Subaru Forester 4 down and averaged 6 mpg. RV ran great...but the banging on some really crappy highways was pretty loud - interstate transitions, particularly at bridges were especially problematic. An ex RV mechanic in Gettsyburg mentioned new leaf springs indicating that he thought the rear end was hanging pretty low. So I crawled under and starting looking around and reading some on the internet. My camper has about a 10 ft rear tire overhang and it's "only" (??) got a 3 leaf spring system installed and they're pretty much flat or arc slightly in a 'frown'. The rubber bumper stop that is pressed against the frame is pretty squashed...I have Firestone Air Bags but I noticed they weren't making much of a difference in ride height. The banging problem has been prevalent since I purchased the RV about 10 years ago - PO even commented on it when I drove it - but I am pretty sure the rear end is sagging more over the past couple of years.I read somewhere that Ford 'experimented' with a 3 leaf spring system and that it didn't really work out. I'm having trouble sourcing replacement springs and not sure of what to get. I know someone is going to mentioned rear axle weight, but I don't know it.Any thoughts? Thanks in advance!Ryan

You might try just a general internet search for a spring shop in your area. They should be able to build you some new spring packs, and it might be cheaper than you would have imagined. But I can guarantee you they will need the motorhome weights before they can build anything,

The "banging" is almost certainly the airbags bottomming out. What PSI are you running? They should go up to 100 psi.And yes, new leaf spring will do wonders. Your cheapest option would be take offs from a salvage yard E450. The 3-leaf setup normally was only used on E350s with an under 6,000# RAWR, and your rear axle weight I bet is at least 8,000 pounds.

If nothing else take measurements of the spring pacs and then research what model springs will work. Find some in a wrecking yard and have them install. The air bags should lift the rear as they are probably the 5000 lb type. You didnt say how much air is in them. I run 55-65 in mine and yes you will get occasional hard hits but nothing is a sure thing. Are you sure they hold air? Go here and ask about the springs, folks are pretty knowledgeable:https://www.ford-trucks.com/forums/forum128/Also look in some truck magazines, they have ads for springs and stuff and would be a good start on finding replacements. Dont forget new hangers and bushings.https://search.yahoo.com/search?p=rear+springs+ford+van&fr=uh3_groups_web_gs

Try Deaver Springs they manufacture aftermarket springs.https://deaverspring.com/

Note that the rear leaf springs on (some? all?) E series chassis of that vintage are rather flat by design, and appear on casual inspection to go straight on a slight diagonal rather than having much or any obvious smile shape. I'm not suggesting you don't have some spring issues to look into--it certainly does sound like you very well might; but going merely on the spring shape can be misleading on these vehicles if you're not familiar with the design.If the shocks are worn, it would be a good idea to replace them as well. A weak or worn shock is going to allow the suspension to bottom out more easily on a sudden transient than a new one (among other things). The rear shocks are not hard to replace on the Ford E series unless the motorhome builder has done something silly to limit access.

Class C rear end sag and banging! | Good Sam Community

77rollalong
Explorer
Oct 26, 2019
Our 1977 26 foot e-class ford had firestone 5000lb air bags in the back to help.. due to there age I replaced them with a set of PacBrake and it makes a big difference in the ride and the ride level as well
pianotuna
Nomad III
Oct 26, 2019
Hi Phil,

I've never owned an RV with a built in generator.
pnichols
Explorer II
Oct 26, 2019
pianotuna wrote:
Hi,

This morning I took my ride into a spring shop. They suggested the best route was to add a leaf or two on both sides. I had weight measurements for them--and they will "beef up" the driver's side to compensate.

They were not happy with the 11.5 foot overhang which is increased by my generator cage (offset to the passengers side to try to shift some weight). But there is no way practical way to fix this. Fortunately the wheel base to length ratio is about 53%, so driveablity is not too horrible.

They will be welding the broken air bag brackets on both sides.

Thanks to this thread for making me rethink just going to E-550 springs.

Don ... what happened to your built-in generator ... or is that what you meant by "generator cage"?
pianotuna
Nomad III
Oct 25, 2019
Hi,

This morning I took my ride into a spring shop. They suggested the best route was to add a leaf or two on both sides. I had weight measurements for them--and they will "beef up" the driver's side to compensate.

They were not happy with the 11.5 foot overhang which is increased by my generator cage (offset to the passengers side to try to shift some weight). But there is no way practical way to fix this. Fortunately the wheel base to length ratio is about 53%, so driveablity is not too horrible.

They will be welding the broken air bag brackets on both sides.

Thanks to this thread for making me rethink just going to E-550 springs.
ron_dittmer
Explorer II
Oct 24, 2019
rgnprof wrote:
added a new leaf to each side, about 1100 lbs additional support per side

ryan
1100 pounds per side is significant. Good for you!

I do wonder what the actual load is on your 4 rear tires. If you get the rig weighed and discover they are over-loaded, there are available E-rated tires designed to handle 600 extra pounds (per tire) over the typical E-rated RV tires most of us have.

Keep that in mind, just in case.
rgnprof
Explorer
Oct 21, 2019
Finally had a chance this fall break to try out the RV with the new add-a-leaf spring. I went with an add-a-leaf that I bought from ATS out of the Philadelphia area (they are great to work with and I can highly recommend them).

Anyway, added a new leaf to each side, about 1100 lbs additional support per side...installation was pretty straightforward and we drove the rig this weekend about 500 miles. Definitely made a difference - ride is better and sits a little higher in the rear, which was very noticeably with my Subaru connected and when I pulled out of backed in to my slightly inclined driveway.

I still get a "BANG" sometimes on pretty abrupt transitions in the highway, but seems better. Not sure how to address that problem.

Overall, I'm pretty satisfied.

ryan
Chum_lee
Explorer
Sep 08, 2019
The problem with buying/using/replacing your springs with "used springs" is that they fatigue over time. For the most part, IMO, you have no way of knowing the condition of used springs without trying them out on your rig. (unless you KNOW the condition for sure) Class C E350's are real tough on springs because they are almost always overloaded or close to it. Age is another factor. Adding "helper" springs to already worn springs may be of little long term help but that's your choice. There's nothing like the ride of a new vehicle which usually comes from replacing ALL the worn suspension/steering parts. IMO, making the suspension "too stiff" is something you'll probably regret later. You all ready know what it's like when it's too soft.

Chum lee
pushtoy_2
Explorer
Sep 08, 2019
rgnprof wrote:
Thanks for all the quick replies!

I ran the air bags at about 80 lbs - this typically raises my coach only about 1 1'2" - maybe 2"...

My shocks are Bilsteins - I installed them around 2011, 2012 and about 30k miles ago.

I have called 3 different online places, the last being Deaver (thanks bear). They were very helpful and to confirm Drew, they said that it's hard to just look at the springs and see a problem and that most likely the problems with these springs are the bushings! They said from new they have little "curve" to them...

He actually suggested adding a leaf - they have a kit specific to my application. Replace the bushings if needed, but he said they frequently don't because they're ok. The factory tapered 3-leaf spring is rated at 3450 lbs, so it's likely the coach has always been 'under springed'...

I'm strongly considering this route.

I would like to find some replacement rear frame rubber bump stops - mine have clearly taken some punishment. But, I'm having trouble finding these - my Ford dealers around are pretty much a waste when it comes to parts for this old coach.
a company called sumo makes heavy duty bump stops
rgnprof
Explorer
Sep 07, 2019
After a lot of reading and talking with folks - and not having much success tracking down anything used - I have decided to try the add-a-leaf option. I have had numerous conversations with the guys at ATS Springs in Pennsylvania and they've been very helpful. Ordered a kit with one leaf per side rated at 1150 lbs each...Also bought a new polyurethane bushing kit from Energy Suspension - not sure if should or will replace the bushings yet???

Has anyone done this on an E350 chassis? Any trick to it?

Doesn't look that hard, but every time I start a project thinking that, something always seems to come up!

Thanks,
ryan
Hank85713
Explorer
Jul 20, 2019
look at craigslist for dal/ftw and other local areas. I saw some parts vans there with mainly frame and suspension parts. Might require a road trip on your part but...............

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