CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Front coil springs keep breaking

    I hit a speed bump in a dark parking lot going faster then one normally would because I didn't see it.  A few weeks later I noticed my suspension was way too bouncy and found out I had a broken spring on the front drivers side.  The mechanic replaced it with a strut assembly from the junk yard but over the next week I noticed the right front spring getting worse. It turned out to be broken also.
   He replaced that and a couple months later I was pulling into a parking lot (slowly) and with my wheels turned I hit the entrance ramp and heard a loud snap like a shotgun. There was a tin can rattling sound after that until whatever was making the noise either fell off or rattled itself down to somewhere it couldn't move. When I took it in the mechanic said the front drivers side spring was broken again.  It was at the bottom of the coil. 
  I'm going to get new tires because they're pretty worn, and an alignment.  I've read that these things can contribute to suspension damage but having the drivers side go just from easing on to an entrance ramp seems a bit extreme.   Can they tell if a used strut assembly has some life left in it or is it just a matter of luck?  Is there anything else I should be checking?

Now I can almost read it

In my opinion, the mechanic did you a disservice by replacing one strut with a used strut. You need the car examined by a front end specialist. Seems to me something else is worn, bent, or broken causing the spring failures. Then you can proceed. Then replace both front struts with new assemblies. I don’t think your car is safe to drive.

5 Likes

Simple answer is NO, you cannot tell is a spring is likely to snap by looking at a used spring. You can be assured that science does, indeed, work and both springs, with similar use both broke. The concept is “fatigue life of steel” and cycles to failure.

Buy NEW springs and have them installed. Used springs will just keep breaking.

4 Likes

No offense, but this is a half-answer.

Yes, new springs are better than old, but most vehicles have springs that are life-of-the-car. It’'s unusual for a spring to break, to say the least, and one breaking a few months after major front-end trauma to a car is likely not a coincidence.

You can put in new springs, but if there’s frame damage or other issues that are putting stress on the spring in a way that it was not designed for, the new springs will also break. I’m with @Purebred, this needs a deeper diagnosis than throwing parts at it.

1 Like

No, that is wrong. Especially with respect to coil springs mounted on struts and especially in the modern (last 30 years) era. They do not have infinite life as the springs are stressed beyond the “knee” in the stress strain curve for steel. This is done for weight savings.

Nearly all springs today are also E-coated (epoxy paint) to protect them from corrosion sites developing and shortening their life. Modern springs must also be handled more carefully so as not to nick the coating and creating a corrosion site and stress riser.

3 Likes

And don’t forget, this is a Freelander, one of the less reliable Land Rovers. And that’s saying a lot!

1 Like

That is reminiscent of a line from that old song about doing The Limbo.
How low can you go?

:smirk:

1 Like

It’s not wrong. I didn’t say that springs have an infinite life. Neither do cars. But springs can easily last 1-2 decades and several hundred thousand miles. Are they identically-performing to a new spring at that point? No; but they don’t generally just break, and they’re no worse for wear than the rest of the car.

It IS wrong. Springs are not life-of-the car. I used to design these things into strut assemblies for a major auto components manufacturer.

If you live where roads are smooth and relatively flat, they may last the life of your car. If you live where roads are rougher, have more hills, more salt on the roads and stroke the springs farther they will break before the car ends its life.

Google “broken car springs” and see how many images are posted of coils springs with the ends broken off.

Ford Taurus’ were notorious for this. They had a recall in the 90’s that added a protective plate to keep the spring from puncturing the tire when it broke. They didn’t replace the spring, mind you, just added a shield.

Our 2002 Ford Taurus did not have the shield. Three springs broke on that car when the car was 6-10 years old. One of the broken springs went right through the tire, stopping the vehicle in its place.

1 Like

Purebred has the perfect answer, here.