Coil vs Leaf for 4x4 Conversion?

[h.grenade]

Ujoint says that leaf is better, quadvan and others say that coil is better. I tend to believe that coil would have better highway manners and better articulation off road but I am just basing this on guessing : ) I currently have a Baja Grocery Getter lift from WeldTec Designs and the van handles great but it does wander a small amount on the road. The steering is nice and light though so its easy to drive long distances.

Any thoughts from someone who has driven both? thx

Edit - Also, Hey! First time posting here long time reader. I have a 2011 E350 EB with TufPort hard top. Currently 2WD but it looks bad ass!

[E-350]

Heyhey! Welcome!

Being on the same level you are right now (Weldtec) and talking myself in and out 4x4 here is my personal take on everything I read for now.
Eventually I would decide between UJoint or ExpoVans/ MGmetalworks.
One being leaf‘ed, one being coil‘ed up front.

Summary:
Take what you prefer :-)

I think eventually it comes down to what you like driving. Both kits seem to be top notch, all people are happy with either conversion, both kits allow you to raise the bar and go place where nobody expects a van to see.

Watching Matts Offroad and Trail Mater you can also see the same: 2 philisophies and both work. Trail Mater swearing on leafs as they are easy, offer „added safety in case one leaf breaks and he’s doing exttem stuff.
Matt going for coils on his rigs and the heavy duty wrecker and also running trails as if it would be nothing.

I would try to drive both and decide afterwards.

[1der]

Originally Posted by E-350

I would try to drive both and decide afterwards.

And this right here is the critical path decision point. I have advised people to seek out members with each conversion and politely ask if they would be willing to let you drive or at least ride in their van. I would not hesitate to drop $500 in airfares plus a case of beer/bottle of ?? if that is what it required before dropping between $15k and $20k on a conversion to get a real feel for what to expect.

Keep in mind any solid front axle conversion is minimum 4 inch lift which is the minimum. Suspension up travel before hitting the bump stops is something to really watch out for. Sway bar quick releases help with articulation but can be problematic with the loads/weight of a van..

fwiw - We opted for the Agile TTB coil conversion, which is no longer available. We had a QuadVan TTB for 15 years which member Wirehead has now.

TTB because highway ride and manners were very important to us. Out of 50,000 miles we put on our rig, less than 10,000 miles has been offroad, and even less, of course, in 4x4. But when the 4x4 was required it was worth it! We are not extreme wheeling our van, but in snow, sand, and rocky trails the 4x4 has been great along with the peace of mind. On washboard and those unavoidable big highway dips the TTB has been equally great. It is really too bad no one is doing the TTB any longer.

My recommendation in most cases is LSD rear and locker front. if you are not doing snow then locked front and rear is really nice.

[shenrie]

I’ve only driven one uj van and one expo van other than my quigley. So that’s all I have to compare with. Couldn’t do any off road with the expo van, and only did off-road (dirt road, no technical stuff) with the uj van. Ride quality of the expo van was better than my quigley on pavement, but not by leaps and bounds. Turning radius of the quigley was definitely better than the uj, but the off-road ride between the two seemed very similar on that particular dirt road. If I had to choose which one rode better I’d have to say my quigley with the rip kit. I don’t recall which shocks were on the batvan, so it might not even be a fair comparison.

Bottom line, as suggested, which conversion is better isn’t something the forum can answer for you. All we can provide is what we personally like and why. Driving each setup is what’s going to be the deciding factor.

Post up where you live. There’s some very generous members that are part of this forum that might be able to help sway your decision with a ride or drive. Ive been handed the keys to a few members vans for things that definitely helped make expensive decisions and their help was more appreciated then they will ever know.

[b. rock]

Spring rate choice makes a big difference. Coils will probably be off the shelf, but with a handful of options. Leaves will be custom.

I've had a lifted 2wd w/ camburg, and now an advanced 4x4 with alcan leaf springs. The alcans are better on washboard, but that's about it. Advanced cut corners elsewhere, and I'm getting into swapping to MG coils.

If going DIY, coils will be a little bit cheaper based on kit pricing.

[Steve Hunt]

Timberline Vans (Golden CO) has a good pros/cons write up on Leaf vs Spring

https://www.4x4vans.com/planning

[clicker44]

I hate to say it but you should sell your van and just buy this and you will come out ahead financially and have a bomber van.

https://www.sportsmobileforum.com/fo...tor-31254.html

Take it straight to Fiberine and add a high top for +$5k and youre in under $40k for a really really nice 4x4 van.

[vandiesel]

I have had both and currently have a deaver leaf sprung SMB 4x4. Leafs ride like a plush cadillac for me and that is because the springs are progressive rate and have a lot more travel that coils. My quadvan 7.3 rode fine on the road and fairly well off road. I'm not sure you can really go wrong either way if both are properly setup and have tuned springs and the right shocks that are valved correctly for the van. Turning radius is something not to be overlooked either. My van turns on a dime now and is MUCH better than stock 2wd which I have also. Come drive mine anytime in Portland.

[REF]

^^^^Not sure that leaf sprung vans, or anything riding on leaf springs will have better ride quality than a coil, comparing when they are both properly set up of course.
Typically, leaf springs are considered to be able to handle greater weight, while coils are known to have better ride qualities on road and greater articulation and wheel travel off road.
There are certainly exceptions, Quigley comes to mind, not exactly known for their plush ride quality, at least not without doing modifications to address known and obvious shortcomings.

[motovan_mn]

Originally Posted by REF

^^^^Not sure that leaf sprung vans, or anything riding on leaf springs will have better ride quality than a coil, comparing when they are both properly set up of course.
Typically, leaf springs are considered to be able to handle greater weight, while coils are known to have better ride qualities on road and greater articulation and wheel travel off road.
There are certainly exceptions, Quigley comes to mind, not exactly known for their plush ride quality, at least not without doing modifications to address known and obvious shortcomings.

I've read this is well, though I can't quite wrap my head around why that might be.

Both types of suspension consist of a spring (coil or leaf) and a damper. If you model that as a mass-damper system, it doesn't matter what type of spring you are using. What matters is the spring rate and damping rate.

So maybe something else comes into play? Does the radius arm or 4-bar linkage used in coil systems allow the solid axle to move more easily than an axle constrained by a leaf spring?

Of course this is all assuming a solid axle conversion. Something like the TTB is a different animal entirely, and I 100% believe the onroad/offroad advantages of that kind of system.

The OP hasn't responded in a while, but if you are in the Minneapolis area I'd be happy to let you ride in or drive my van. UJOR 6" conversion.