The real reason the Mustang has a solid rear axle

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ElFenix

Elite Member
Super Moderator
Mar 20, 2000
102,404
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How is this old news? I've seen people most many times about the huge cost savings of the solid axle in the Mustang, which is the opposite of reality.

We are having a spirited discussion about IRS vs solid axle, despite Pulsar's hateful post.

well, let's see, the blog itself is dated june 2009. i'm going to guess it's probably been discussed on here before. maybe even before that june 2009 date.


it's the same argument we've all had before, with all the same people bickering back and forth.

and pulsar's post is dead on. why would you assume that the estimate for the IRS was accurate when the estimate for the live axle was not? i see people like to talk about one of the focus rehashes the same way: the project overran its estimates so bad that the actual figure came in at more than the estimate for localizing the european focus. but why would you assume the estimate to localize was correct? seems to me that ford had a lot of problems like that, which hopefully mulally has fixed.
 

punjabiplaya

Diamond Member
Nov 12, 2006
3,495
1
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The real reason the mustang doesn't have IRS is so that people can argue about it on the internet.

It's probably a bunch of things: budget, engineering, politics, etc...
 
Aug 23, 2000
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well, let's see, the blog itself is dated june 2009. i'm going to guess it's probably been discussed on here before. maybe even before that june 2009 date.


it's the same argument we've all had before, with all the same people bickering back and forth.

and pulsar's post is dead on. why would you assume that the estimate for the IRS was accurate when the estimate for the live axle was not? i see people like to talk about one of the focus rehashes the same way: the project overran its estimates so bad that the actual figure came in at more than the estimate for localizing the european focus. but why would you assume the estimate to localize was correct? seems to me that ford had a lot of problems like that, which hopefully mulally has fixed.

This is because people latch on to what they like and can not see or fathom that the thing they like could have faults as well.
A lot of people are unable to see that there are multiple ways to achieve the same end, and those ways will all have their faults and weaknesses.
 

Throckmorton

Lifer
Aug 23, 2007
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If you hit something so hard that it would cause the whole thing to move, it doesn't matter if you are in a IRS or have a log out back you're going to feel it.

The problem is not feeling it. It's the fact that the tire going over a bump reduces traction at the other tire by changing its angle. It has nothing to do with hitting something hard or big or whatever. Every bump in the road has that effect. If you run very low air pressure you might be immune-- but it's apparent even with my big soft 31x10.5x15 tires at 26psi.

The Mustang has and continues to keep a solid rear axle, because for getting power to the ground, it still rules the roost.
This is why the 2010 GT with 315HP is able to have trap times only .1 seconds off of the much higher horse power V8 Camaros and Challengers.
The 2011 5.0 will rape those cars.

If you want to go as fast/quick as possible. Get a solid rear axle. IF you want IRS and want a pony to puttz around in buy a Slomaro or Challenger.

But what does getting power to the ground at the drag strip have to do with the real world?

You can belly ache and hem and haw over Fords "horrible" choice to keep a solid rear axle out back, but when it comes down to it. They are smarter than GM or Dodge on the subject. Hence they are the only ones to have kept their pony car in production with no stoppages. The Camaro and Challanger can say that.

Ford has always been better at marketing. I agree that the Mustang is the best of the current crop, solely because it doesn't weigh 4000lb, but what sells Mustangs is the brand. My niece got a 2005 Mustang when she was in high school not because of handling or drag strip prowess, but because "it's a Mustang".
 

Throckmorton

Lifer
Aug 23, 2007
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This is because people latch on to what they like and can not see or fathom that the thing they like could have faults as well.
A lot of people are unable to see that there are multiple ways to achieve the same end, and those ways will all have their faults and weaknesses.

But I'm well aware of the pros and cons of solid axles and IRS/IFS. That's why I have a Jeep with two solid axles.

That's twice as many as your Mustang. It must be twice as fast!
 
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CurseTheSky

Diamond Member
Oct 21, 2006
5,401
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Anyone that complains about a bumpy ride due to the solid rear axle hasn't driven - or ridden in - a true sport / track car. ANY vehicle, solid axle or IRS, that has the suspension tuned for sports applications is going to be some degree of unforgiving in ride quality.

If you want a cushy daily driver, you're shopping for the wrong type of vehicle.
 

Throckmorton

Lifer
Aug 23, 2007
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Anyone that complains about a bumpy ride due to the solid rear axle hasn't driven - or ridden in - a true sport / track car. ANY vehicle, solid axle or IRS, that has the suspension tuned for sports applications is going to be some degree of unforgiving in ride quality.

If you want a cushy daily driver, you're shopping for the wrong type of vehicle.

Nobody here is complaining about the ride-- just the handling effect of a solid axle on bumpy roads that exist in the real world.
 

mb

Lifer
Jun 27, 2004
10,233
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Anyone that complains about a bumpy ride due to the solid rear axle hasn't driven - or ridden in - a true sport / track car. ANY vehicle, solid axle or IRS, that has the suspension tuned for sports applications is going to be some degree of unforgiving in ride quality.

If you want a cushy daily driver, you're shopping for the wrong type of vehicle.
I knew not to expect cushy but I certainly didn't like how the car hopped around on rough roads. For example the Genesis Coupe is not all that smooth either but it felt a lot more stable and predictable.
 

Pulsar

Diamond Member
Mar 3, 2003
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The problem is not feeling it. It's the fact that the tire going over a bump reduces traction at the other tire by changing its angle. It has nothing to do with hitting something hard or big or whatever. Every bump in the road has that effect. If you run very low air pressure you might be immune-- but it's apparent even with my big soft 31x10.5x15 tires at 26psi.

The 'problem' is people who can't accept anything other than their own opinion. The mustang is, frankly, the best 'muscle' car on the road right now anywhere near that price point. Best in performance and best in looks (admittedly a little subjective on this point). However, instead of picking on the problems the others have - too much weight, lack of power, lack of visibility out the windows, you're picking on the best of the lot.

Ford has always been better at marketing. I agree that the Mustang is the best of the current crop, solely because it doesn't weigh 4000lb, but what sells Mustangs is the brand. My niece got a 2005 Mustang when she was in high school not because of handling or drag strip prowess, but because "it's a Mustang".

Then you say this type of bullshit. Ford is better at marketing. Yet the product they have is the best one out there. You claim that the car is the best, but the reason it sells is the brand. That's totally nonsensical. A Charger, Challenger, or Camaro are all equally desirable brands. However, when one is better, it sells better.

You say it's better, the reviews say it's better, but it's not better. Cool. We get it.

You came in here with an age old argument that's been proven pointless. We get it. Even though it's the best thing on the road in it's price point, you don't like a solid rear axle. Despite the reviews, despite the performance, you'll dislike the car until it drops the solid rear axle. Got it.

With regards to my hateful post - there isn't any hate there. It just gets old seeing the same trolls posting the same poorly thought irrational stuff over and over again.
 
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Arkaign

Lifer
Oct 27, 2006
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Yeah this argument has been beaten into the ground, we've covered it exhaustively before in the forums here. Pro auto reviewers have universally praised the handling of the new Mustangs, and the fact that it doesn't have IRS doesn't appear to make any appreciable difference outside of *VERY* rough roads, where you'd have to be an idiot to drive fast enough to upset both rear tires to the point of losing grip (and that kind of recklessness would knock an IRS-equipped vehicle off the road as well).
 

Howard

Lifer
Oct 14, 1999
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A lot of people argue about things that don't actually matter (to the driver). I suppose it's just human nature.

What doesn't matter? Weight, drag coefficient, gearing, power, torque, chassis material, window glass thickness, brake size, brake material, OEM tire size, wheel weight, wheelbase, bore/stroke ratio, rod/stroke ratio, track width, suspension type, etc.

What does matter? External dimensions, straight-line acceleration (and numbers), lap times, braking numbers (both instant and repeated), top speed, interior dB, comfort, gas mileage, driveability, fun factor, aesthetics, interior/cargo space, etc.

If you disagree, answer me this: would you reduce the weight of the vehicle by 100lbs at a cost of decreasing gas mileage by 2mpg?
 
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Throckmorton

Lifer
Aug 23, 2007
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The 'problem' is people who can't accept anything other than their own opinion. The mustang is, frankly, the best 'muscle' car on the road right now anywhere near that price point. Best in performance and best in looks (admittedly a little subjective on this point). However, instead of picking on the problems the others have - too much weight, lack of power, lack of visibility out the windows, you're picking on the best of the lot.



Then you say this type of bullshit. Ford is better at marketing. Yet the product they have is the best one out there. You claim that the car is the best, but the reason it sells is the brand. That's totally nonsensical. A Charger, Challenger, or Camaro are all equally desirable brands. However, when one is better, it sells better.

You say it's better, the reviews say it's better, but it's not better. Cool. We get it.

You came in here with an age old argument that's been proven pointless. We get it. Even though it's the best thing on the road in it's price point, you don't like a solid rear axle. Despite the reviews, despite the performance, you'll dislike the car until it drops the solid rear axle. Got it.

With regards to my hateful post - there isn't any hate there. It just gets old seeing the same trolls posting the same poorly thought irrational stuff over and over again.


You have failed at basic logic. Just because the Mustang is the best musclecar that exists right now doesn't mean the solid rear axle was the better choice. It was chosen to save $100 per car, at the cost of real world handling on roads that aren't perfectly smooth. And what nobody on this forum realized until now is it ended up costing $98 more.


Following your fanboy logic, I can't say the Challenger is the best looking of the competitors, because I also said the Mustang is the best. The best has to be perfect in every way, and all the others have to be terrible in every way, right?

I don't see how you can deny that the Mustang is so successful because of the brand. That was exactly the reason it survived and the previous Camaro/Firebird were axed. What is your explanation for the popularity of the Mustang with teenage girls?
78634-Ponygirl.jpg
 
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exdeath

Lifer
Jan 29, 2004
13,679
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Same reason the Corvette has leaf springs and pushrods: because they work while being cheaper, smaller, and lighter, and it pisses off brand snobs who wouldn't buy it anyway no matter what it had.

Ive run into people that mouth off about my car "outdated technology pushrods, blah blah" I pop the hood and it clearly says DOHC, "ok but it has a truck rear end" I say nope its a built IRS, then finally I get "uh uh um yeah but its still a Mustang".

Some people are just retarded and like to call themselves engineers despite failing high school.
 
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Throckmorton

Lifer
Aug 23, 2007
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Same reason the Corvette has leaf springs and pushrods: because they work while being cheaper, smaller, and lighter, and it pisses off brand snobs who wouldn't buy it anyway no matter what it had.

The Corvette leaf springs have nothing in common with pickup leaf springs, despite what Jeremy Clarkson says. They're single leafs with wishbones. I have no idea why you would use that as an example. I've never even heard of any snobs not buying a Corvette because it has completely unique leaf sprung independent wishbone suspension.

It does benefit from the pushrod engine because it's much more compact than DOHC, which allows the low hood.
 

exdeath

Lifer
Jan 29, 2004
13,679
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The Corvette leaf springs have nothing in common with pickup leaf springs, despite what Jeremy Clarkson says. They're single leafs with wishbones. I have no idea why you would use that as an example. I've never even heard of any snobs not buying a Corvette because it has completely unique leaf sprung independent wishbone suspension.

It does benefit from the pushrod engine because it's much more compact than DOHC, which allows the low hood.

Likewise with the Mustang's stick axle, its nothing like the leaf spring hung stick axle of a 1950s truck.

Most people who complain about it then try to gain credibility by saying they did actually drive one wouldn't know the difference, they just went in predispositioned to hate on it because they already know in their mind its there. If you replaced it with an IRS and didn't update the brochure, people would still say they didn't like the "solid axle".
 
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Throckmorton

Lifer
Aug 23, 2007
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Likewise with the Mustang's stick axle, its nothing like the leaf spring hung stick axle of a 1950s truck.

Most people who complain about it then try to gain credibility by saying they did actually drive one wouldn't know the difference, they just went in predispositioned to hate on it because they already know in their mind its there. If you replaced it with an IRS and didn't update the brochure, people would still say they didn't like the "solid axle".

Big difference. The Corvette has NOTHING in common with a leaf sprung truck-- the geometry is pure double wishbones, the leafs are used in a completely different way, and the leafs themselves are single piece. The only thing in common is that it's not coil sprung.

But the Mustang's solid axle, even though it's not leaf sprung like a truck, is still a solid axle, and the deficiency on rough roads still exists.

You might as well argue that they should make the Mustang FWD, because engineers have done remarkable things with FWD lately. After all, the Focus RS performs pretty well! Much better than the Escort of yore right? There are many FWD cars that can beat RWD ones around a track, so surely a FWD Mustang would be perfectly fine.

Speaking of the Focus, did you notice how much Ford touted the independent Control Blade rear suspension? They said it was better than the beam axles on the competitors, and they were right!
 
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Bignate603

Lifer
Sep 5, 2000
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Yes, and the Grand Cherokee I had rode like a Cadillac with its coil sprung solid axles.

But the Mustang isn't a luxury car-- it's a performance car.

Yes, it's a performance car and its performance beats its competitors. It's the best out there, so stop whining about how they screwed it up.
 

halik

Lifer
Oct 10, 2000
25,696
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It sure has. What the bench racers on this forum and many others seem to forget is that the best riding cars for years and years had a solid rear axle. In fact to this very day one of the best riding cars you can buy, the Lincoln Town Car has a solid rear axle.

If your definition of best riding is floaty and essentially no control, then sure...
Airsprings don't always mean awesome ride...
 

HarryLui

Golden Member
Aug 31, 2001
1,518
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You know the Explorer and Expedition both have IRS right? And those are vehicles that are very negatively affected by the technology. They are worthless offroaders unlike the previous generations, and the IRS are much bulkier and heavier to deal with the truck duty stresses that a solid axle easily handles. But they got IRS for lower load floors and slightly better ride (I doubt cornering grip was a factor)


Explorer and Expedition got IRS mainly because of this.
http://www.youtube.com/watch?v=qeqvS_fsjcs&feature=related
 

halik

Lifer
Oct 10, 2000
25,696
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Big difference. The Corvette has NOTHING in common with a leaf sprung truck-- the geometry is pure double wishbones, the leafs are used in a completely different way, and the leafs themselves are single piece. The only thing in common is that it's not coil sprung.

But the Mustang's solid axle, even though it's not leaf sprung like a truck, is still a solid axle, and the deficiency on rough roads still exists.

You might as well argue that they should make the Mustang FWD, because engineers have done remarkable things with FWD lately. After all, the Focus RS performs pretty well! Much better than the Escort of yore right? There are many FWD cars that can beat RWD ones around a track, so surely a FWD Mustang would be perfectly fine.

Speaking of the Focus, did you notice how much Ford touted the independent Control Blade rear suspension? They said it was better than the beam axles on the competitors, and they were right!

The corvette set up is closer to torsion bars than truck leaf springs IIRC. Aren't they spring across, parallel to center axis of the rear wheels?
 

Throckmorton

Lifer
Aug 23, 2007
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The corvette set up is closer to torsion bars than truck leaf springs IIRC. Aren't they spring across, parallel to center axis of the rear wheels?

It's a single leaf that goes all the way across. It has an anti roll effect. When both wheels go up, the leaf bows upward on both sides. But when the Corvette leans, one wheel goes up, the other goes down, and the two sides fight each other and the leaf gets bent into an S. So the anti roll bars are thinner than they would normally be.

http://www.carbibles.com/suspension_bible.html
transverseleafspring.jpg
 
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RocksteadyDotNet

Diamond Member
Jul 29, 2008
3,152
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Hey, your Monaro was a flop here. LOL @ IRS
Newer technology doesn't mean better Pushrod motors are newer than overhead cam, but I bet you think Overhead cams are newer thus better.

The GTO and G8 were succesful. You guys JIYP over those cars.

And OHC is was way better than pushrod. If you think otherwise then you're an idiot.