IFS vs SFA

Se7enLC · **Posted:** Wed Aug 17, 2005 9:36 am

Ok, so one of the main reasons the liberty gets no respect as an offroad vehicle is because of the Independant Front Suspension. Everyone is always saying how a Straight Front Axle is the way to go for offroading.

The question I have is - why? Please don't just say "articulation" and not explain, or "cuz every other offroad vehicle has it". There must be some reason SFA is better. I initially was thinking it had to do with keeping the wheels on the ground more, but wouldn't IFS do a better job of that? (since one wheel being up in the well should have no effect on the other). Thoughts? Comments? Especially diagrams and photos :-)

( And side note - If hardcore KJ-hating jeepers want to disclude the Liberty, they should think about forgetting the Grand Cherokee, too - the 2005 model year looks very not-offroad compared to the liberty, and the SRT8 model should sum it all up )

SethX9 · **Posted:** Wed Aug 17, 2005 10:02 am

Well....the first thing to clear up is to define what is meant by "off road". It seems it's the rock crawling crowd that has decided SFAs work best for what they do but for almost all other situations the IFS/IRS is the choice. The military decided on independent suspensions for the HUMMV. And the SCORE-type trophy trucks are almost always independent suspension. Perhaps that would be a clue that "better" is going to depend on what type of off-roading is being done.

As to the Liberty not getting respect as an off-road vehicle I think that has more to do with the way the Liberty was marketed. I mean, has anyone ever even SEEN a Liberty-only ad? Now compare that to the rock'n'roll ads Nissan put out for the Xterra. DS marketed the Liberty to the suburban stay-at-home mom demographic.

LibertyCRD · **Posted:** Wed Aug 17, 2005 10:09 am

Generally speaking, solid axles have fewer moving parts and are stronger and less prone to breakage. Not to mention they are easier to modify and work on. So they are the top choice for hard-core off-road trail and rock use.

BUT, for an all-around rig that you are going to use on the street too, you can't beat IFS. It's much better on-road, and can have advantages off-road as well like you pointed out. It keeps more of the tire's contact patch on the ground at all times than solid axles will.

kevh · **Posted:** Wed Aug 17, 2005 10:46 am

another advantage of sfa is leverage (which is why it is the choice for rock crawling. as one side is forced upwards by an obstacle, the other side is forced down towards traction

a downside to this the vehicle body tends to roll more as the "high" side in the above situation is fully compressed.

an ifs (and irs) vehicle will stay more level. as long as both ends are locked, ifs/irs is becoming more and more popular in rock crawling because the vehicle tends to stay more level

Se7enLC · **Posted:** Wed Aug 17, 2005 11:09 am

SethX9 wrote:

As to the Liberty not getting respect as an off-road vehicle I think that has more to do with the way the Liberty was marketed. I mean, has anyone ever even SEEN a Liberty-only ad?

I take it you haven't seen the ad for the "All new 210 HP Jeep Liberty Snowthrower"?

Or the one where the liberty is seen driving down from a volcano? (with small text at the bottom saying something like "don't really drive on a volcano")

Guyute1210 · **Posted:** Wed Aug 17, 2005 12:49 pm

Se7enLC wrote:

Or the one where the liberty is seen driving down from a volcano? (with small text at the bottom saying something like "don't really drive on a volcano")

Now that's funny...don't drive on a volcano...what a riot! :lol:

SethX9 · **Posted:** Wed Aug 17, 2005 12:50 pm

Oh hey...my bad....I have seen the volcano ad. The snowblower ad probably didn't test well in the furnace of hell that is Phoenix, AZ

hhmm.....I wonder how many young women bought a Liberty because Kristen Kreuk [sigh] drives one on the TV show Smallville.

Se7enLC · **Posted:** Wed Aug 17, 2005 1:46 pm

SethX9 wrote:

Kristen Kreuk [sigh] drives one on the TV show Smallville.

I thought she did, because I remember seeing one (a purple one, no less!)

But then in a later episode, I saw the inside of it, and it was a blazer! I have all the episodes recorded on MythTV, and from what I can tell, they just changed her vehicle around a few times, keeping only the "sorta small/midsize purple suv" constant.

Ahh, WB. When will you learn to keep things consistent? (And why is it that Lana drives a brand new SUV, Chloe drives a new VW Beetle, and clark is somehow without a car at all. I can kinda see lana, she does own her own business, but chloe? Since when do journalist internships pay enough for new cars when in highschool?)

dirtykj · **Posted:** Wed Aug 17, 2005 1:54 pm

Se7enLC wrote:

I have all the episodes recorded on MythTV

MythTV eh? Good choice, good choice

Wonder how many Jeepers are Linux users.

FreedomKJ · **Posted:** Wed Aug 17, 2005 6:18 pm

dirtykj wrote:

Wonder how many Jeepers are Linux users.

Me me me!

(we need a tux smiley.)

Ubuntu Hoary on my workstation at my job and Debian Sarge on my dedicated server.

hoss75 · **Posted:** Wed Aug 17, 2005 11:15 pm

Hacked DirectTivo here..

Tokyojoe · **Posted:** Wed Aug 17, 2005 11:30 pm

Steering my Liberty over Linux, Apple, and Windows to get back to the topic.

IFS vs SFA...anymore reasons?

Guyute1210 · **Posted:** Thu Aug 18, 2005 10:17 am

Win @ work, and Linux @ home...also a hacked TiVo...

FreedomKJ · **Posted:** Thu Aug 18, 2005 1:07 pm

Whenever I get into a discussion about IFS vs. SFA with my monster TJ and YJ driving buddies I just point out that I can drive 6 hours to the trail in comfort (without buying a tow rig and trailer,) wheel all day long (also comfortably,) and then drive 6 hours back home, never having to deal with "death shakes," bad handling or a bumpy ride.

If all you're going to be doing is rock crawling then build yourself a dedicated buggy and be done with it, but if your offroader is also your daily driver like mine is, then you can't beat IFS.

If I had a third vehicle to use as my daily driver and the KJ was just for play time, then I can guarantee you I'd be first in line for an SFA.

jnoden · **Joined:** Fri Jul 08, 2005 8:03 am **Posts:** 11

Hacked Direct Tivo? I didnt think there was a hack for the P4 yet. I have gone legit and have a Direct TV tivo but I split the $100/month with two friends.

Se7enLC · **Posted:** Thu Aug 18, 2005 1:46 pm

FreedomKJ wrote:

Whenever I get into a discussion about IFS vs. SFA with my monster TJ and YJ driving buddies I just point out that I can drive 6 hours to the trail in comfort (without buying a tow rig and trailer,) wheel all day long (also comfortably,) and then drive 6 hours back home, never having to deal with "death shakes," bad handling or a bumpy ride.

I agree completely! IFS is practically necessary for a daily driver.... But I'm still not sure I've seen any real reason to go with SFA, even FOR rock crawling....so far it was just "less parts", "simpler", "cheaper" and a vague guess about leverage across the axle. Pros for the IFS include the nice on-road handling, better ground contact, less body roll when flexed.

Is it really just that there aren't currently any IFS lifts greater than 3" or so? As far as I can tell, the fact that SFA technology has been around much longer than the relatively new idea of independant suspension is the only reason it's more commonly used for that sort of thing (imagine how sweet a buggy would be with 4-wheel Independant suspension with a fair amount of travel (a foot or two) ).

hoss75 · **Posted:** Thu Aug 18, 2005 2:43 pm

jnoden wrote:

Hacked Direct Tivo? I didnt think there was a hack for the P4 yet. I have gone legit and have a Direct TV tivo but I split the $100/month with two friends.

Lets stop hijacking this thread.. go here:

http://www.lostjeeps.com/forum/phpBB3/vie ... 0346#10346

Guyute1210 · **Posted:** Thu Aug 18, 2005 2:44 pm

jnoden wrote:

Hacked Direct Tivo? I didnt think there was a hack for the P4 yet. I have gone legit and have a Direct TV tivo but I split the $100/month with two friends.

P4???

Anyway, Hacking DirecTiVo is possible, and has nothing to do with stealing service (not being legit). If you want to know more about hacking a DirecTiVo, i suggest checking out the TiVo Community website.

YJBeef · **Posted:** Mon Aug 29, 2005 10:17 pm

FreedomKJ wrote:

Whenever I get into a discussion about IFS vs. SFA with my monster TJ and YJ driving buddies I just point out that I can drive 6 hours to the trail in comfort (without buying a tow rig and trailer,) wheel all day long (also comfortably,) and then drive 6 hours back home, never having to deal with "death shakes," bad handling or a bumpy ride.

I find that almost true, have you ever ridden in a long-armed TJ??? When we went for a 8-9 hr ride to the beach........ :lol:

we took the TJ cause it is actually more comfortable than the KJ :roll:

go figure, not what I'd have expected neither. Now the TJ is still stock so that comes in to play a little. Now to go the other way, the KJ is a lot more comfortable than my YJ which is lifted but then again leaf springs were not built for comfort in mind :lol:

IFS vs SFA

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