T of F: Everything else equal, I would prefer solid axles to independent suspension?

[Martinjmpr]

Well, first off I think you need to distinguish between front and rear. I like my solid rear axles and actually passed on a possible vehicle choice (the 05+ Nissan Pathfinder) because it has IRS.

But, having come of age during the solid axle/leaf spring era, I have to say I don't miss it. Wife's YJ (which is leaf-sprung) rides like a buckboard and is terrible on washboard.

I think the biggest advantage to SFA is that it's easier/cheaper to lift. If you're not running huge tires the advantage is minimal.

[Cee-Jay]

Well, first off I think you need to distinguish between front and rear.

At the time, I decided that independent all-around was rare enough (excluding crossovers) that it wasn’t worth making the distinction, but that may have been a mistake. 1) Some crossovers are quite capable and frankly the line between crossover and real deal SUV isn’t always clear. 2) More and more trail worthy bloodlines are moving in that direction: Hummers, Gen 3 Monteros, Patrol, Grand Cherokee, Explorer, etc.

So I think you make a fair point and in fact I was thinking last night that it might have been better to create a multiple choice allowing for a) solids front and back, b) IFS + solid rear, c) independent front and back, or d) Doesn't matter/Not Important.

[LaOutbackTrail]

The biggest proponents to IFS/IRS rigs are Jeep and Land Rover at the moment. But who wants an electronically controlled suspension system?

[F1Chase]

For the terrain I'd be likely to see, I'd choose a well built TTB setup. As my habits tend to take me to the desert more often then not, the strength of the TTB (vs IFS) and it's ability to more easily create large amounts of wheel travel (vs solid axles) would be more beneficial to me.

As for IFS vs solid axle debate, I'd go IFS consisting of a well built and thought out design, kinda like the 4Wheel & Off Road Ultimate F150.

[HillbillyfromAL]

True

I'll go out of my way not to buy anything with independent suspension. I still haven't had much luck finding a solid axled ATV though.

[Erik N]

As for IFS vs solid axle debate, I'd go IFS consisting of a well built and thought out design

A picture is worth 1000 words

[HillbillyfromAL]

The HMMWV also has gear reduction hubs to provide more clearance the only Civilian vehicle I know that has them on an independent suspension is the H1. For the complexity I bet they could have done it simpler with some Mog axles. I've spent a fair amount of time in HMMWV's, but they are too wide to take on the trails I drive.

[Buliwyf]

That Hummer is also likely around $120,000+.

I prefer solid axles. But it really depends on the truck.

I'll only approve IFS if it has rack and pinion steering. Combining old school steering box type steering and IFS is an Ackerman and bumpsteer nightmare that eats tires joints and rods. So that limits IFS to light duty trucks.

And "IFS rides better" is really not a quality opinion. Some people think softer is better. I think control and proper damping are important. And such things are not going to be soft on a big truck. Yes my fleet of GM's have a softer ride than the Fords. But those same GM's are very, very hard to control going over a bumpy bridge on the freeway while the Fords maintain control very nicely. Really I feel safer and more in control when I'm in the stiffer Fords. Same for gravel roads. The Fords and Dodges are somtimes harsher, but they outperform the GM's big time.

Lately some of our GM's have been improved and come with better dampers and spring rates. They drive better, but are no longer as plush or soft as the Fords. They actually have a stiffer ride.

I just got a new GM 3500 Express van. It's not a terrible machine, but it bounces 3 times every time it hits a bump. GM has lost all ability to build quality safe suspensions. Shame on GM. I'm actually considering sneaking some Bilsteins on the front of my company vehicle on my own dime. That's how bad it is. Shocks alone won't fix the problem, but hopefully they'll help a little.


Some other solid axle plus's that I don't think anyone mentioned:
+can be lighter overall
+decent ackerman settings
+strong enough for smoother auto lockers like the Detroit and Yukon.
+made out of steel not aluminum
+consistant ground clearance. IFS ground clearance changes, and bouncing over an object your clearance can drop 4" easy. Braking down a hill, your front axle will have less clearance than it would going up the hill with IFS.

+easy on steering tie rods. When IFS hits a bumps and the suspension moves, bumpsteer tugs on the tie rod with enormous force. Solid axles don't have this.
+not much to align, or the need to
+simpler
+cheaper
+swappable. I can pull a dana 50 out of a Ford and install a Super 60 without breaking a sweat. Your stuck with whatever is under a Chevy.


PS: The Ford IFS Dana 50 is the devil. Nothing brings me more pleasure than chopping up one of those junkers with a torch. And solid axle Mustang>IFS Mustang Cobra.

[redthies]

Wife's YJ (which is leaf-sprung) rides like a buckboard and is terrible on washboard.

The YJ is not really a good example of what leaf springs and a solid front axle are about. I drove a few of those (both stock and modified) back when they were new. Absolute total crap. They have to be the worst example out there.

I like a sfa for the simplicity and strength, but then I load my F350 up with 2500 lbs of cargo on a weekly basis. I think Dodges coil sprung sfa is the best compromise between comfort and capability. I won't get into the maintenance needs though...

[Hj61 12ht]

I would never consider an overland 4x4 without a solid front axle, you have extra CV joints to fail, all those rubber boots to rip open, those ball joints to fall apart...
Toyota realize that lots of people don't like the idea of IFS which is why they offer the 105 series cruisers in parts of the world where it really matters.