Advantages of Solid Axle over IFS???

Squatch

Squatch

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Following behind a TJ today on I-5 got me to thinking: What are the advantages to the TJ's solid front axle over an IFS? I have very little experience with any sort of serious off road challenges, but I do have some thoughts and preconceived notions on the subject. I would like to pose the question to folks who have real world experience off road, to which there seem to be more than a few on this forum. So...how 'bout it?
 
The only real advantages to solid axles could be attributed to off-road performance. For an on-road passenger vehicle (especially a daily driver), IFS is far superior, especially when it comes to handling. The only real on-road benefit I could see to solid axles would be if you're towing or carrying tremendous amounts of weight and need a truck with big tires (or dual tires).

IFS is inherently more complex than solid axles in terms of maintenance of course. Keep in mind that all of those off-road buggies and race trucks as far as I'm aware use a solid rear axle, but IFS in the front.

Now if you want to talk about rock crawling, I may be wrong, but I'm not sure any of those big rock crawling rigs are using IFS.

Be thankful your Jeep has solid axles. They really don't ride that bad IMHO, and they are so easy to work on.
 
Simplicity for sure :)
But it's also been proven to excel offroad, forcing weight to the opposite tire via the axle.
But as with anything, ride quality suffers some for offroad ability.
 
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Chris said:
The only real advantages to solid axles could be attributed to off-road performance. For an on-road passenger vehicle (especially a daily driver), IFS is far superior, especially when it comes to handling. The only real on-road benefit I could see to solid axles would be if you're towing or carrying tremendous amounts of weight and need a truck with big tires (or dual tires).

IFS is inherently more complex than solid axles in terms of maintenance of course. Keep in mind that all of those off-road buggies and race trucks as far as I'm aware use a solid rear axle, but IFS in the front.

Now if you want to talk about rock crawling, I may be wrong, but I'm not sure any of those big rock crawling rigs are using IFS.

Be thankful your Jeep has solid axles. They really don't ride that bad IMHO, and they are so easy to work on.
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Thanks, Chris. Some of the preconceived notions I mentioned fall in line with what you're saying. I also suspect that today's auto manufacturers are targeting the general population with their 4WD vehicles, and not the true off road enthusiast, hence the better handling (I guess) IFS. Hell, hence AWD over 4WD... But one of the things I've wondered about is while the IFS seems to me to offer more ground clearance up front, the rear of the vehicle would still have the same limitation our TJs have for rear axle clearance over obstacles, unless they had an IRS, as well. So what would be the advantage to an IFS at that point? Also, seems that the with the IFS having more CV joints, it would be inherently weaker than the TJ's solid axle. If that's true, the point goes to the TJ...
 
Squatch said:
Thanks, Chris. Some of the preconceived notions I mentioned fall in line with what you're saying. I also suspect that today's auto manufacturers are targeting the general population with their 4WD vehicles, and not the true off road enthusiast, hence the better handling (I guess) IFS. Hell, hence AWD over 4WD... But one of the things I've wondered about is while the IFS seems to me to offer more ground clearance up front, the rear of the vehicle would still have the same limitation our TJs have for rear axle clearance over obstacles, unless they had an IRS, as well. So what would be the advantage to an IFS at that point? Also, seems that the with the IFS having more CV joints, it would be inherently weaker than the TJ's solid axle. If that's true, the point goes to the TJ...
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Yes. Modern 4x4 vehicles (i.e. the Toyota 4Runner) are being targeted to the masses. These are the people who want a 4x4 to do things like go to the mountain, drive on the beach, maybe do some gravel roads. They aren't marketing them to the guys who want to crawl rocks, bang up their underside, and flex out their suspension to the max. If that was the case, they would be selling them with solid axles.

Very few vehicles these days come with solid axles anymore. The Wrangler only maintains them because if the Jeep engineers were to put IFS on a Wrangler, the cries of blasphemy and sacrilege would spread like wildfire all over the internet.

Other than the Wrangler though, most all modern trucks have solid axles in the rear, and the very large diesel trucks (i.e. Dodge Rams) have solid axles front and rear because they need them.
 
Squatch said:
This instantly reminded me of the YJ's square headlight fiasco... ;)
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The Jeep engineers know this too. I heard rumors that they considered putting IFS on the new JLs, but that was quickly shot down by others within the company, because they knew how bad that would go over on the internet. They're right too... You don't make a Wrangler without solid axles. At that point you might as well make the top non-removable.
 
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LiveAxles.

Cheap, BulletProof, Easy to LIFT.

The list of disadvantages is way longer.

But as long as the JK/JKU keeps selling like hotcakes, cashcow !!
Jeep won't risk many changes.
 
Chris said:
The Jeep engineers know this too. I heard rumors that they considered putting IFS on the new JLs, but that was quickly shot down by others within the company, because they knew how bad that would go over on the internet. They're right too...
Click to expand...

Nice to know that they're paying attention...
 
Travel and more specifically articulation is the big advantage of a solid axle from a performance perspective. They are also cheaper to manufacture, less parts count.

On road performance suffers with a solid axle though not hugely. The JK goes to show how refined they can make one. They ride pretty nice.

Another driver toward ifs is ride height. Lower ride height means better mileage and the engineers can tuck the body down between the wheels a bit more with ifs.
 
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