IFS vs. Solid Axle

[jeeperjohn]

You cant really say that IFS is weaker than a solid setup. The strength of them is more determined by the quality of the parts than the overall design.
For example, a Hummer H1 (none of that weak sauce h2) has IFS setup.

I saw plenty of H1 front drivetrains get trashed while I was in the Army. It was strong but not as strong as a solid axle.

 

[tomcat]

Call me crazy, but I don't see any front driveshafts in that rig...

driveshafts pictured here (2nd pic):
http://www.pirate4x4.com/forum/showpost.php?p=9842728&postcount=6

 

[winkosmosis]

Well said TiRod. They won't ever make anything like the XJ again. Just watered down excuses for Jeeps. We're just lucky they made 2 million of them while in production so they will be sticking around for a while. Personally, I have two and don't plan on getting rid of them.

Are you kidding me? XJs are great, but to imply that they were some kind of offroad beast is ridiculous. Most of them didn't even come with recovery points much less skid plates, ground clearance, or decent sized tires. They were designed for the street, just like the YJ. Solid axles alone don't make a vehicle an offroader.

Say what you will about H3s and FJs, but all of them come with recovery points, skid plates, generous ground clearance, and big tires that you can't fit on an 80s or 90s Jeep without a big lift.

 

[Slip Kid]

Well said TiRod. They won't ever make anything like the XJ again. Just watered down excuses for Jeeps. We're just lucky they made 2 million of them while in production so they will be sticking around for a while. Personally, I have two and don't plan on getting rid of them.

:bawl::tears:

 

[mizedog]

IFS does Well on the Highway, as a Daily Driver, or for Road Racing. If one Wishes to...

All I Know Is That It Would Drive Me Crazy To Capitalize So Much! How in the heck do you do that (not that I want to start copying you!)?:dunno:

 

[mizedog]

Don't forget that many IFS set ups use a rack set up instead of a gear box and pitman arm. This means that the rack 'n' pinion aren't isolated from bump steer and can fail from side blows.

I know I'm NEVER going back to IFS. I learned my lesson. When you can't articulate, you teeter totter over big woops where an articulating rig stays relatively level.

 

[Pharaoh XJ]

One more advantage of SFA:

Faster (safer) to tackle the dunes around here ( not glamis ), it is definitely better than IFS. The dunes around here are stone cut you never know what is on the other side ( vertical & horizontal inclination), with SFA you have more traction most of the time 4 wheels are on the ground.

Thats why Bowler Wildcats used to be a big deal in Dakar = faster through the dunes.

But when it comes to the rough stuff I have to admit IFS rules, although I must say that with the same budget you can't build an IFS strong as a SFA

 

[cher96]

All I Know Is That It Would Drive Me Crazy To Capitalize So Much! How in the heck do you do that (not that I want to start copying you!)?:dunno:

My Daughter Thinks I am Nuts Doing that. She is Always Looking at me Weird when I Post. I Enjoy Doing it and Now it has Become Habit. Can't Seem to Stop it. It's Just my Crazy Style of Posting.

I'm Extremely Weird to Say the Least.

 

[IXNAYXJ]

KOH is far from flat.

No. it's Not. I have Only Seen the KOH on Cable Once and it was Only 30 Minutes of Highlights. Honestly, I have No Idea who is the Driver or Owner of that Rig is.

The Only Time I have Seen Rigs Like that Perform was in Baja Style Offroad Races on Cable. I'm Pretty Ignorant when it comes to Other than Auto Maker 4x4s.

You got one thing right.

Shannon Campbell's IFS KOH buggy did just fine in the rocks...and over other vehicles:

Here's a picture I took of it:

-----Matt-----

 

[jeeperjohn]

Say what you will about H3s and FJs, but all of them come with recovery points,

Because they need them

 

[cher96]

So I'm sure everyone can chime in on the Solid Axle side here being a Cherokee forum, but I'm well aware of the basic benefits of a solid axle for off-roading and would really like it if anyone had some extra not so appearant advantages of the Solid Axle.

The reason I ask is that I am writing a business proposal for my English Class on why Toyota should redesign the front suspension of the FJ Cruiser to incorporate a Solid Axle instead of IFS. Basically my theory behind it is to increase sales via better competition with the Jeep Wrangler. Not that I really give a rats ass about the FJ because I'd buy 4 Cherokees before I ever bought one FJ, but it was a do-able topic that I thought of quickly.

Any input is greatly appreciated, and links to other websites about the subject is good too! Thanks.

You got one thing right.
-----Matt-----

I may be Ignorant and Mistaken about many things. At Least I Know it and Will Say So and Not Try and Prove Myself Otherwise.

I believe the OP was Needing Information on Production Front Solid Axle Suspensions verses Production Independent Front Suspensions and NOT Specialty Suspensions on Specialty Vehicles. But then Again, I'm Not So Ignorant That I can Not Read. IMHO

 

[veedubshafer]

Are you kidding me? XJs are great, but to imply that they were some kind of offroad beast is ridiculous. Most of them didn't even come with recovery points much less skid plates, ground clearance, or decent sized tires. They were designed for the street, just like the YJ. Solid axles alone don't make a vehicle an offroader.

Say what you will about H3s and FJs, but all of them come with recovery points, skid plates, generous ground clearance, and big tires that you can't fit on an 80s or 90s Jeep without a big lift.

I didn't say solid axles alone make a vehicle an "offroader". Also, what average consumer wants those ugly recovery points anyway? they obnoxiously big and the older ones I see are rusting like crazy even if they've never been used. And how many of these things will be tearing up the pavement even with 300-400k on the clock? Definately not any H3's and 'yota engines are certainly not what they used to be.

 

[Milford Cubicle II]

Because they need them

Exactly. :roflmao:

Most of them didn't even come with recovery points much less skid plates, ground clearance, or decent sized tires. They were designed for the street, just like the YJ. Solid axles alone don't make a vehicle an offroader.

Wait... XJ's don't have ground clearance? Damnit I'm sellin mine I got duped! I thought ground clearance was standard but apparently you only get that with the Limited package :banghead:

And if XJ's or YJ's were designed for the street then why do they have SFA's?

Say what you will about H3s and FJs, but all of them come with recovery points, skid plates, generous ground clearance, and big tires that you can't fit on an 80s or 90s Jeep without a big lift.

Sounds like you're saying SFA's don't make a better offroad vehicle but recovery points and skid plates do??? :confused1

And the reason they can fit bigger tires is called BODY ON FRAME, the same reason they NEED those bigger tires to get the ground clearance they have. Put XJ's on 31's and they make H3's and FJ's look like Toyota Camry's.

 

[winkosmosis]

Exactly. :roflmao:



Wait... XJ's don't have ground clearance? Damnit I'm sellin mine I got duped! I thought ground clearance was standard but apparently you only get that with the Limited package :banghead:

And if XJ's or YJ's were designed for the street then why do they have SFA's?



Sounds like you're saying SFA's don't make a better offroad vehicle but recovery points and skid plates do??? :confused1

And the reason they can fit bigger tires is called BODY ON FRAME, the same reason they NEED those bigger tires to get the ground clearance they have. Put XJ's on 31's and they make H3's and FJ's look like Toyota Camry's.

But they didn't come with 31s. They came with dinky 27" tires, no protection whatsoever, and no recovery points. The lack of recovery points alone is inexcusable for an alleged offroad vehicle.

You know why they say "Jeeps are built not bought"? Because for a long time, you couldn't buy an offroad capable Jeep. They KNEW most people weren't going to offroad, and they built them for those people. FJ and H3 target those same people, with the difference being that they COME with skids, recovery points, big tires, and lockers were an option from the start.

The solid front axle was just convention for AMC then Chrysler IMO, and almost disappeared from the Jeep lineup under Daimler's iron fist. Of course they articulate better but do you really think the beancounters cared? No, they just cared how many they sold to soccer moms.

 

[bvillebud]

I don’t necessarily agree about the solid axle having more articulation, (but I don’t want an IFS). I think that the IFS has the ability to isolate the input from one wheel over the opposing wheel no matter what the other side is doing; on a straight axle, the other side of that long bar is going to be impacted directly by what is going on at the opposite end. Maybe this has more to do with control than articulation, if so forgive my typo, but you get the point. Desert racers and high end specialty vehicles have been doing IFS for years, with great success, truck pulling where you don’t need articulation, but have to put power to the ground reliably - not so much (or at all). It just kills me that you can’t buy a ½ ton truck with a live front axle.

The straight axle does have plenty of theoretical advantages as well as plenty of real world ones.

Most (if not all) IFS are aluminum – weaker than an iron axle
Plenty of locker choices for a straight axle – almost none for IRS
Simplicity of straight axle means less maintenance & less to go wrong when TSHTF
Strength - CV joints are typically a weak link

 

[tomcat]

But they didn't come with 31s. They came with dinky 27" tires, no protection whatsoever, and no recovery points. The lack of recovery points alone is inexcusable for an alleged offroad vehicle.

You know why they say "Jeeps are built not bought"? Because for a long time, you couldn't buy an offroad capable Jeep. They KNEW most people weren't going to offroad, and they built them for those people. FJ and H3 target those same people, with the difference being that they COME with skids, recovery points, big tires, and lockers were an option from the start.

The solid front axle was just convention for AMC then Chrysler IMO, and almost disappeared from the Jeep lineup under Daimler's iron fist. Of course they articulate better but do you really think the beancounters cared? No, they just cared how many they sold to soccer moms.

jeep offered skids, recovery points and even lockers as options. you could buy mopar performance Detroits you know, and i don't fault jeep for doing that. you want to slam them for that, fine, but they made it available. if you knew you were going to need it, you ordered it that way. I would much rather an a-la-carte vehicle than not being able to opt out of something like a crappy sat-nav system. when mags build up wranglers, they often start with a 2wd model, because they are cheaper, and going to rip out the axles, and put in an atlas anyway. are you going to fault jeep for making 2wd vehicles now? they are a business afterall

 

[Root Moose]

I'm not reading the entire thread to see if this has been mentioned before...

Toyota has set precedence with a vehicle being available in both IFS and SFA form. Land Cruiser UZJ100 vs UZJ105. It's the Land Cruiser version of the Lexus LX470. In other markets it is available in SFA form (UZJ105).

SFA is more robust and reliable, can go longer between servicing typically, easier on the steering gear, more capable off road. IFS is rides better. And that's about it.

 

[custom_fab]

How about that wet dream ford had with their twin beam hybrid solid axle/ifs. Talk about absolutely no flex, and crappy ground clearance.

 

[Root Moose]

TTB isn't as bad as Internet lore would have you believe.

 

[rocknxj]

Weight, performance, and manufacturing cost should be prioritized in your plan from the engineering and business aspect.

Performance, demand, and maintenance cost should be considered from the customer's aspect.