'09 Ram: All-Coil Suspension

[SVT666]

The Humvee, HMTT, and Abrams M1A1 main battle tank also use coil springs.

And they all weigh much more then a 1/2 ton pickup.

[SVT666]

Actually this brings up an interesting question I've had.

Everyone tells me "you shouldn't tow 10,000 pounds with a 1/2 ton."  It seems like some unwritten rule that people only tow 75% or 60% of that rating.  But I have to ask, do the trucks really break if you tow at the limit?  Obviously half ton owners aren't going to be towing 10,000 pounds all the time. But if Toyota and GM rate their trucks to tow 10,000 pounds then I sure as hell expect to be able to tow something close to that at least part of the time without damage to my truck. I've exceeded the gross weight rating of all my cars plently of times (4 people in the Z06, 7 people in the Supra, 8 in the pathfinder) and I've never even considered anything breaking because I know the engineers put down rather conservative estimates.  Did manufacturer's urge to one-up each other do away with those safety margins?  I mean I'd expect a 10,000 pound tow rating to mean that I can safely tow 10,000 pounds with confidence that my truck isn't going to split in half.  If I have no confidence in that, than all these tow ratings are useless because you never know what the true safe amount to tow is.

The more I think about it, the more it makes sense that things like tow rating should have some kind of standardized system like SAE horsepower or crash ratings.

It's not breakage that I'm worried about, it's staying in control.  My neighbour has a small 5th wheel that weighs in the vicinity of about 5000 lbs.  He tows it with a 1/2 ton Dodge and he says the trailer dictates where the truck goes.  He has towed the same trialer with a 3/4 ton Dodge and he says it's like night and day.  The 3/4 ton tows much better.  When I towed my car through the rockies on a trailer that weighed more then 1500 lbs without the car, I was towing about 4000+ lbs and I barely knew the car was there, but in certain situations I could see that if you added 2000 lbs to that trailer it would have been a handful.

The problem is that the manufacturer sets the tow rating and they can set it to whatever they are comfortable with on the liability side of things.  When Toyota came out with their new Tundra and it had a tow rating of 10,000 lbs, Ford increased their tow rating on the F-150 overnight with no changes to the truck itself just to stay ahead of Toyota. 

[Eye of the Tiger]

I guess that's why we always break our front coils at work, but the rear suspension never has a problem.

Sounds like you need something more than a 1/2 ton.

[Submariner]

I'll remember that the next time I have a million dollars to burn.

I bet they can tow a lot, too.

I also have a good feeling they get 5 stars or better, in government crash tests.

[the Teuton]

Weren't you a lot shorter then?

Maybe 6-8 inches, to be honest.

[GoCougs]

I guess that's why we always break our front coils at work, but the rear suspension never has a problem.

I still have yet to see a material technical criticism of rear coils.

Maybe Oshkosh Truck Corporation (uses coils on many, many of its heavy duty trucks) is all wet:

[GoCougs]

And they all weigh much more then a 1/2 ton pickup.

Yes, exactly.

[Soup DeVille]

Then again some people do use the trucks, and max payload means something different when you're bouncin over the tops of two-tracks...

What do you think the picture I postd is off of, a Subaru Brat?

Or do you know many people who regularly haul more than the 250,000 pounds or so a typical freight boxcar can weigh?

[Soup DeVille]

I bet they can tow a lot, too.

I also have a good feeling they get 5 stars or better, in government crash tests.

Actually, M1s are damned dangerous vehicles to be in an accident in.

Of course, the tank itself is just fine, but the occupants can be beaten up pretty severely real easily.

[S204STi]

I just don't like how low and girly these trucks are all becoming.  I remember in 1999 when I had to jump to get into a Ram 2500 at the auto show and subsequently climb into it.  My mom with two bad hips could get in and drive that Ram.

I disagree bro.  I would much rather my car's crash structure absorb a crash with these monsters rather than my freakin' A-pillars (and my upper torso).

[S204STi]

I still have yet to see a material technical criticism of rear coils.

Maybe Oshkosh Truck Corporation (uses coils on many, many of its heavy duty trucks) is all wet:

Burned!    (Sorry Tave, but he's right.)

[Tave]

Burned!    (Sorry Tave, but he's right.)

Because that's the same coil they're going to put into the Ram

[Tave]

I still have yet to see a material technical criticism of rear coils.

Maybe Oshkosh Truck Corporation (uses coils on many, many of its heavy duty trucks) is all wet:

I thought I've made it clear I'm talking about private-duty light pickup trucks.

Maybe you'd care to mention some more irrelevant machinery that no small buisness owner in the country can afford?

[Tave]

Sounds like you need something more than a 1/2 ton.

We use 3/4. The front shocks and springs are prone to break down after heavy use, but it's not a huge deal -- we fix the truck and keep working -- while the rear suspension lasts the life of truck.

[Soup DeVille]

Because that's the same coil they're going to put into the Ram

What it proves is that there is no inherent load limitation on a coil spring that's relevant to your argument. Because you know of coils springs breaking, that does not mean that the concept is flawed.

Should I also point out that for years hardcore offroaders have been scrapping their stock leafs springs and replacing them with coils?

[Tave]

What do you think the picture I postd is off of, a Subaru Brat?

Or do you know many people who regularly haul more than the 250,000 pounds or so a typical freight boxcar can weigh?

Oh, I guess you're right. If a railroad coil is good that means the Ram's will be too.

[Tave]

What it proves is that there is no inherent load limitation on a coil spring that's relevant to your argument.

Huh? I'm talking about coil springs Dodge uses, and you're talking about industrial machinery.

Because you know of coils springs breaking, that does not mean that the concept is flawed.

Someone could probably design a fucking coil that would hold up the world, but that's not what I'm talking about. I'm talking about the real world, not a physics blackboard.

[Tave]

I still have yet to see a material technical criticism of rear coils.

I mentioned that your list of vehicles cost a lot, but I guess that was easy to ignore.

[Soup DeVille]

Oh, I guess you're right. If a railroad coil is good that means the Ram's will be too.

Are you intentionally being difficult?

What it means is that the Ram's suspension is not automatically bad simply because it has coil springs. It may or may not be well engineered. That has nothing to do with it being coil springs or not.


I remember having exactly this same argument with many Jeepers in 1997.

Then when the TJ proved itself more capable than any previous Jeep: they shut up.

[Tave]

Should I also point out that for years hardcore offroaders have been scrapping their stock leafs springs and replacing them with coils?

Hmm, sounds a little expensive.

Most hardcore offroaders also aren't interested if their hobby makes sense financially. They do it because they like it.

[Soup DeVille]

Hmm, sounds a little expensive.

Most hardcore offroaders also aren't interested if their hobby makes sense financially. They do it because they like it.

I'm done with this argument.

Save this page and re-read in five years.

[Tave]

Are you intentionally being difficult?

What it means is that the Ram's suspension is not automatically bad simply because it has coil springs. It may or may not be well engineered. That has nothing to do with it being coil springs or not.

I'm not saying it's going to be bad, I just mentioned some concerns, based off my own experience with Dodge suspensions. It could be a great set-up for all I know. Good for Dodge if it is.

I remember having exactly this same argument with many Jeepers in 1997.

Then when the TJ proved itself more capable than any previous Jeep: they shut up.

As a clarification, I'm talking about durability, not performance. The front end of our work trucks are very capable untill a shock blows.

[Tave]

Save this page and re-read in five years.

HA! Yeah, it's going to be eating at me the entire time.

[Eye of the Tiger]

Hmm, sounds a little expensive.

Most hardcore offroaders also aren't interested if their hobby makes sense financially. They do it because they like it.

I doubt a coil spring setup is really more expensive than an equivalent leaf setup, as long as you're not talking about conversions. Coils just have more potential, which might lead to higher prices.

[Eye of the Tiger]

As a clarification, I'm talking about durability, not performance. The front end of our work trucks are very capable untill a shock blows.

For durability's sake, there are multiple leafs to back each other up if one fails, but generally only one or two coil springs. A 40-year old rusted out leaf spring can still function with cracks in it, but not a coil.
But, if the suspension is built and maintained properly, it won't be a problem in either case.

[GoCougs]

I thought I've made it clear I'm talking about private-duty light pickup trucks.

Maybe you'd care to mention some more irrelevant machinery that no small buisness owner in the country can afford?

Literally tens of thousands of small business owners every year buy $100k - $150k class 6 and class 8 trucks.

For whatever reason, you're on a tear using anectodatal data - Which brings up another point: If you're breaking front coil springs on Dodge Ram you are simply abusing the truck well beyond its designed intent. Way WAY beyond. It's quite hard to break a coil spring.

I mentioned that your list of vehicles cost a lot, but I guess that was easy to ignore.

Quite the opposite - that they cost a lot lends credence to coil suspensions, in that those vehicles are specifically very heavy and/or harsh duty. Coil spring design is about as basic as it gets - most domestic cars up until the '80s were rear-leaf sprung, including the performance variety (Mustang, Camaro, Challenger, etc.) - now none of them are.

If Dodge can can use rear coils without sacrificing hauling and towing capability, and it doesn't cost material any more $$, there is virtually zero detriment to the consumer.

I also note the just recently the 4X4 F-250/350 went from leafs to coils in the front, and I also note that the Avalanche has always used rear coils, as have recent iterations of the Expedition, Tahoe, Durango, Armada, and other 1/2-ton based SUVs.

(EDIT - I was mistaken - the Abrams uses torsion bars, not coils.)

[S204STi]

Because that's the same coil they're going to put into the Ram

Fine.  Let's put it this way:  I used to replace rear leaf springs on a regular basis on the 1st Gen Nissan Frontier, but NEVER replaced a broken front coil on one.  Now which is more durable?

[280Z Turbo]

None of the coil spring naysayers have given a good reason why they're bad.

Do leaf springs have some kind of magical spring rate?

[S204STi]

None of the coil spring naysayers have given a good reason why they're bad.

Do leaf springs have some kind of magical spring rate?

It would seem that, as with all things, you could make either strong enough to suit your needs, however I suppose there is a correlation between beefiness and spring rate.

[Tave]

For whatever reason, you're on a tear using anectodatal data

And I never claimed otherwise. For whatever reason, you can't see that you're using anectodal evidence, too.

Are you intentionally being difficult?

Bingo.