coil-over springs versus leaf springs on E350 camper

[zip]

With my upcoming planned retirement in the next 3-6 months, I still have the hope of a last build being a UJOR 10' box truck. I love what Justin in CO is doing with these vehicles. I am looking forward to seeing what the future is with UJOR CO regarding a possible partnership with other upfitters to sell a turnkey rig with custom sub frame and composite box.
My current retirement goal is to move into my rig and rock climb and mountain bike as long as I have the physical ability and desire. I hope to do this shortly after retiring. I intend to purchase an interim E350 that already has a 4 x 4 conversion and start traveling while waiting to see what happens at UJOR CO. My previous E350 was a Sportsmobile with a Quigley 4 x 4 conversion with coil-over springs. My off roading will just be fire roads to get to dispersed camping. I feel that my Quigley conversion was inadequate for even the most minimal off-road activity. I know that UJOR uses leaf springs in their conversion.
I would appreciate any input on comparing these two different spring setups. Vehicle will probably be a RB weighing 9-10K pounds.
Thanks.
Blair/Zip

When comparing coil-over springs and leaf springs for 4x4 conversions, my Internet research says the following:

• Performance: Coil-over springs offer better ride quality and articulation, making them ideal for off-road travel and providing a more comfortable ride on rough terrain.
• Load Capacity: Leaf springs are generally better at handling heavier loads, making them suitable for heavy-duty applications like construction and farming.
• Customization: Coil-over systems allow for greater customization, including adjustments to spring rate and dampening, which can enhance performance on various terrains.
• Maintenance: Leaf springs are typically cheaper to purchase and maintain, but they require more frequent maintenance due to moving parts.
• Ride Quality: Coil-over systems provide a smoother ride, while leaf springs can be bouncier, which may affect comfort on long drives.
  
  
  
  

 

[DirtWhiskey]

I'll add that coils typically have a better turning radius. So key. Godspeed on the project sounds like a good and noble one!

 

[ujoint]

I'll start by clearing up your terminology so we're comparing things correctly. A "coil over" is a shock/coil combo like a lot of modern trucks (or my flatbed) have. The shock and coil are combined as one unit. I think what you're referring to is a coil/shock setup like your Quigley had. They're separate. A coil over system can be made to out articulate a leaf setup but this isn't common in a van. Requires a 100% custom setup like my flatbed, lots of fabrication and the juice isn't worth the squeeze. Nor is it as reliable as the leaf setup. More wearing parts, harder to diagnose issues, noisy, etc.

Our leaf setup out flexes every radius arm or link/coil setup easily. Ride quality is always subjective but there's a reason so many coil 4x4 vans have been converted to the UJOR leaf kit over the years. Literally every other 4x4 van converter has had their setup replaced with ours. Our custom spec'd springs don't need fine tuning unless the weight of the rig changes enough to need a new spring rate. Off the shelf shocks, no custom valving needed. The leaf springs aren't cheap or cheaper than the coil/shock setup but the performance gains are substantial.

So, be careful what you read and what platforms that info is aimed towards. What works for the common truck or jeep isn't always best for our Ford vans. Hope this helps and come for a ride at either shop any time to feel then difference.

 

[ExpoMike]

Also you forgot the torsion bar front suspension. Our Advanced 4x4 GMC van has this (basically from a 1 ton truck parts but it's a custom torsion bar crossmember by them). Even as a 1 ton van, empty, this thing actually rides great.

Each setup has pros and cons.

 

[ujoint]

Also you forgot the torsion bar front suspension. Our Advanced 4x4 GMC van has this (basically from a 1 ton truck parts but it's a custom torsion bar crossmember by them). Even as a 1 ton van, empty, this thing actually rides great.

Each setup has pros and cons.

I think he's referring to the Ford chassis only.

 

[zip]

I'll start by clearing up your terminology so we're comparing things correctly. A "coil over" is a shock/coil combo like a lot of modern trucks (or my flatbed) have. The shock and coil are combined as one unit. I think what you're referring to is a coil/shock setup like your Quigley had. They're separate. A coil over system can be made to out articulate a leaf setup but this isn't common in a van. Requires a 100% custom setup like my flatbed, lots of fabrication and the juice isn't worth the squeeze. Nor is it as reliable as the leaf setup. More wearing parts, harder to diagnose issues, noisy, etc.

Our leaf setup out flexes every radius arm or link/coil setup easily. Ride quality is always subjective but there's a reason so many coil 4x4 vans have been converted to the UJOR leaf kit over the years. Literally every other 4x4 van converter has had their setup replaced with ours. Our custom spec'd springs don't need fine tuning unless the weight of the rig changes enough to need a new spring rate. Off the shelf shocks, no custom valving needed. The leaf springs aren't cheap or cheaper than the coil/shock setup but the performance gains are substantial.

So, be careful what you read and what platforms that info is aimed towards. What works for the common truck or jeep isn't always best for our Ford vans. Hope this helps and come for a ride at either shop any time to feel then difference.

Chris,
Thank you for clearing that up and the education.
Blair

 

[iggi]

Hey Blair,
I'm curious as to where you felt the Quiqley conversion was inadequate?
Sounds like we have similar goals. (climb and bike until we can't)
Unfortunately for me though retirement is probably 3 years away rather than 3 months away.

As for Coils vs Leafs. I've owned 4x4's with both. The ride quality was better with the coils but.. not really a fair comparison as the leafs were rusty and 35 years old while the coils were nearly new.
For any trails that a fully loaded camper is going down, I don't think spring choice matters nearly as much as the quality of the components, the quality of the install and the skills of the driver.

My rolling project is still 2wd (for now) but that doesn't stop me from getting down a lot of fire roads and such.
This is from a few years back but is still one of my fave pics. (no, I wasn't stuck - just had to back up and choose a better line)

IG

 

[IdaSHO]

Biggest benefit to leaf sprung is it isn't coil sprung,
and biggest benefit to coil sprung is it isnt leaf sprung!

In all seriousness, while coil sprung allows for (much) tighter turning radius and better ride for the same load capacity,
its largest downfall is the potential for death wobble, and I imagine this is one serious consideration for those builders that stick to leaf sprung.

Even with near every bushing being sloppy on a leaf sprung solid axle, the thing will still go down the road fairly safely.
You can also (nearly) lift it to the moon with little to no issues.

Coil sprung, all it takes is one marginal bushing/link and you run the potential for death wobble.
And lifting coil sprung isnt nearly as simple. Done right, you may need an adjustable track bar and/or drop brackets.

 

[simple]

I had a 2003 E350 quigley and the suspension design on it was pretty bad. There were no adjustments for the front links to correct axle alignment and it would also bump steer really bad. When I owned it, it wasn't very old and had low miles so I don't think it was wear related.

Vans with 4x4 leaf spring conversions tend to require a bit of lift and then need bigger tires to look right. Unless you need extra clearance and bigger tires, the trade off is tire cost and fuel economy.

A GM cube van torsion bar conversion would be my choice.

I bet a cube van with a locker and a winch would get most places on a fire / logging road. Chains for snow and avoid beach driving.

 

[zip]

Hey Blair,
I'm curious as to where you felt the Quiqley conversion was inadequate?
Sounds like we have similar goals. (climb and bike until we can't)
Unfortunately for me though retirement is probably 3 years away rather than 3 months away.

As for Coils vs Leafs. I've owned 4x4's with both. The ride quality was better with the coils but.. not really a fair comparison as the leafs were rusty and 35 years old while the coils were nearly new.
For any trails that a fully loaded camper is going down, I don't think spring choice matters nearly as much as the quality of the components, the quality of the install and the skills of the driver.

My rolling project is still 2wd (for now) but that doesn't stop me from getting down a lot of fire roads and such.
This is from a few years back but is still one of my fave pics. (no, I wasn't stuck - just had to back up and choose a better line)

IG




View attachment 897348

The main reasons I didn't like the Quigley was the death wobble, bump steer, and it would bottom out going over traffic bumps in parking lots. Rear suspension was big blocks on possible factory leaf springs.

 

[86scotty]

I've had lots of Quigleys and never had death wobble. Not to mention the millions (literally) of solid axle coil sprung trucks running around NOT having death wobble.

Quigley/coil sprung (the most common) conversions are fine conversions for 99.9% of us.

I recommend Agile RIP on any Quigley and improved rear leaves (no tall blocks). My 2011 benefited from Sumo Spring bumpstops as well.

 

[deserteagle56]

Biggest benefit to leaf sprung is it isn't coil sprung,
and biggest benefit to coil sprung is it isnt leaf sprung!

In all seriousness, while coil sprung allows for (much) tighter turning radius and better ride for the same load capacity,
its largest downfall is the potential for death wobble, and I imagine this is one serious consideration for those builders that stick to leaf sprung.

Even with near every bushing being sloppy on a leaf sprung solid axle, the thing will still go down the road fairly safely.
You can also (nearly) lift it to the moon with little to no issues.

Coil sprung, all it takes is one marginal bushing/link and you run the potential for death wobble.
And lifting coil sprung isnt nearly as simple. Done right, you may need an adjustable track bar and/or drop brackets.

^This!

I've owned both leaf-sprung and coil-sprung 4x4 vans. Current one (2007 Quigley) is coil sprung. I live out in the middle of Nevada - very few paved roads. All those rough dirt roads wear out all the bushings on a coil suspension pretty fast - and as mentioned, then you have loose steering and death wobble. I don't use the van all that much anymore - if I did, I'd be looking to have UJoint do a leaf conversion.

 

[deserteagle56]

With my upcoming planned retirement in the next 3-6 months, I still have the hope of a last build being a UJOR 10' box truck. I love what Justin in CO is doing with these vehicles. I am looking forward to seeing what the future is with UJOR CO regarding a possible partnership with other upfitters to sell a turnkey rig with custom sub frame and composite box.
My current retirement goal is to move into my rig and rock climb and mountain bike as long as I have the physical ability and desire. I hope to do this shortly after retiring. I intend to purchase an interim E350 that already has a 4 x 4 conversion and start traveling while waiting to see what happens at UJOR CO. My previous E350 was a Sportsmobile with a Quigley 4 x 4 conversion with coil-over springs. My off roading will just be fire roads to get to dispersed camping. I feel that my Quigley conversion was inadequate for even the most minimal off-road activity. I know that UJOR uses leaf springs in their conversion.
I would appreciate any input on comparing these two different spring setups. Vehicle will probably be a RB weighing 9-10K pounds.
Thanks.
Blair/Zip

When comparing coil-over springs and leaf springs for 4x4 conversions, my Internet research says the following:

• Performance: Coil-over springs offer better ride quality and articulation, making them ideal for off-road travel and providing a more comfortable ride on rough terrain.
• Load Capacity: Leaf springs are generally better at handling heavier loads, making them suitable for heavy-duty applications like construction and farming.
• Customization: Coil-over systems allow for greater customization, including adjustments to spring rate and dampening, which can enhance performance on various terrains.
• Maintenance: Leaf springs are typically cheaper to purchase and maintain, but they require more frequent maintenance due to moving parts.
• Ride Quality: Coil-over systems provide a smoother ride, while leaf springs can be bouncier, which may affect comfort on long drives.
  
  
  

I call BS on Maintenance! Leaf suspensions require more maintenance due to moving parts? What moving parts? Compared to a coil suspension which has to use a track bar, and an upper and lower control arm on both side of the axle???

 

[iggi]

The main reasons I didn't like the Quigley was the death wobble, bump steer, and it would bottom out going over traffic bumps in parking lots. Rear suspension was big blocks on possible factory leaf springs.

Those are common complaints on the Quigley. As noted, there are solutions out there.

 

[rruff]

...and avoid beach driving.

Or just air down.