[LoSilver]

If unloaded, our vehicles run "ass high". The van is pretty bouncy when driving unloaded. Is anyone aware of a lowering spring or some other method to bring the rear down? I'd hate to cut the springs...I have no plans to ever load the van to anywhere near capacity.

 

[Chris]

Consider this:

http://www.vbairsuspensionusa.com/u...Product sheet VB-FA-4C RAM ProMaster V1.0.pdf

You can then choose any height you want, and still preserve the ability to load the van to full GVWR. Not cheap, though.

As a more down-and-dirty approach, you could have a spring shop re-arch the springs a bit, but then you would reduce your load capacity.

 

[Chance]

If unloaded, our vehicles run "ass high". The van is pretty bouncy when driving unloaded. Is anyone aware of a lowering spring or some other method to bring the rear down? I'd hate to cut the springs...I have no plans to ever load the van to anywhere near capacity.

Bouncy or harsh ride comes primarily from springs being too stiff. Stiff springs normally jacks up the rear, but being jacked up in itself doesn't make the ride bouncy or harsh.

If you lower the rear by any method that maintains the original spring stiffness, I doubt you'll improve the ride significantly. You can easily end up low and bouncy.

In my opinion there are two issues here that should be kept separate in order to solve your problem effectively. They are dependent on each other but one doesn't necessarily cause the other.

 

[carnut]

...Is anyone aware of a lowering spring or some other method to bring the rear down? I'd hate to cut the springs...

Don't know how you "cut" a leaf spring.
I'm wondering if there are some lower rate springs available from Europe. The crazy high GVWR on the 1500 didn't make sense to me until I realized that it's a ploy to keep Promaster's out of the CAFE requirements. Anything less than 8500 and they would have to include them. That was part of GM's motivation to drop the 1500 Express and Savanna.
The small Ducato is available in Europe as a passenger van so perhaps there are already factory springs with a lower rate out there. Or, maybe RAM will seize the opportunity with the diesel to offer a lower GVWR that can actually help their CAFE. Then maybe we can source the spring locally. I'm sure that's the part of the motivation for the diesel in the RAM 1500 pickup.

 

[Brian P]

I had the rear springs re-arched to lower the rear by about 60mm by a local spring shop. I don't plan to ever come anywhere close to the full load capacity, so the shortened distance to the bump stops isn't an issue; it's not riding on the bump stops even with my normal loading on board (which is less than half of rated load capacity). Ride is the same.

In fact, you could probably cut one of the convolutions off the bump stop to shorten it if you want it to sit even lower. The bump stop will be stiffer but shorter if you do that - it won't change the ride as long as you are not hitting the bump stop all the time.

I'm very happy with the lower floor height so that it's easier to get motorcycles in and out.

 

[Chance]

Carnut, Ducatos are indeed made with much lower GVWR for Europe, so I'd bet they have leaf springs with lower stiffness. Since Ducatos ride lower, it's also possible they use shorter and or softer bump stops as well for the lower-capacity vans.

Fortunately getting custom springs is relatively easy. I'm not sure going to Fiat is necessary. Plus we'd first have to confirm that they interchange.

 

[carnut]

...Fortunately getting custom springs is relatively easy...

Depends on where you live. In Denver I had no problem getting any custom work done on rapid turnaround. Where I live now it would be a hassle with double shipping and extended downtime involved. If it was a choice of buying new springs for $400 (still keeping the originals) or $200 to send them somewhere for recurve (which still won't change the spring rate) I'd probably spend the extra. If your talking about having custom springs made I'd prefer someone who has experience with the vehicle.

Here's one I found with a quick search.
http://sandersonautoparts.com/fiat-ducato/fiat-ducato-springs/peugeot-boxer-fiat-ducato-citroen-relay-single-leaf-rear
Don't know the spring rate but I'm sure they'd tell you. Sounds like in Europe they have the opposite problem. Many people want HD springs and they charge a premium for them.

In the long run it may cost less to buy new springs. What if you want to sell and the original buyer wants full GVWR? Having done various mods over the years I hesitate to do anything that isn't easily reversible. It's easier to sell.

 

[keithwwalker]

fyi, that VB air suspension system is a factory option in Europe - it self levels, and can lower itself for loading/unloading.
It is great that VB USA is now offering it!!!

 

[keithwwalker]

The VB is 2" lower than stock, & can lower 2.5" for unloading.

 

[Chance]

Looks like the rear is lower than stock, but the front about an inch higher. From there the front seems to lower more than the rear if I'm interpreting specs correctly.

 

[keithwwalker]

Im assuming the VB runs the PM dead level, so perhaps thats why the front was raised.