A couple months ago i snapped a passenger front coil spring. I only replaced that one, but what i have noticed is that the driver side front on some nice smooth roads seems to want to bounce around 45-55 mph. Ive had several places look everything over during the past 2 years, as well as myself while replacing all the things ive had to replace. Im just wondering what are the chances that my front springs were defective from the beginning, being they were not strong enough or weak. Resulting in one snapping and the other allowing the truck to bounce. Anyone think that could be a possibility? I dont have it tore apart im just want to hear what some people have to say about it. Could a weak sping cause a bouncing in the wheel? Just curious.

 

I am not an expert on suspensions, but I am a mechanical engineer and have worked in the automotive parts manufacturing industry. I likely would have replaced both springs once the one was found to be fractured. Two reasons include: 1) High likelihood the fracture was caused by inferior manufacturing/metalurgy (they don't typically fail, unless you drive like Dukes of Hazard), and the mating spring likely came from the same manufacturing lot, so a similar problem could ocurr; and 2) even if not, I would like to have matched springs with equal cycle life as they would be more likely to perform similarly (balanced). I can see where you might have control issues if the two springs are not balanced. Maybe I am wrong, but that's what I would have done. FWIW.

 

Thats what i was wondering about, if they came from the same batch, that both could have been faulty, one being undersprung allowing it to bounce and the other being weak to the point where it snapped.

 

Springs have as tooldad referred to a life cycle.....they eventually wear out and their rebound characteristics change.....so it would be a good idea to change them both...

 

I already changed the one i snapped about a month and a half ago, i think im going to do the other, good thing i have a father in law with a large spring compressor.

While on that subject, if i get a small leveling kit, how much would it change everything if i didnt get it aligned?

 

Well, I installed a 2" AS kit and immediately got mine aligned by stealership. Still wore the crap out of the outside edge of my new expensive tires. Turns out they aligned "to spec" but that was not appropriate (too much camber) for the new arrangement. Going to add eccentric alignment cams soon to add more camber adjustment capability and take it to 4WheelParts to align. Point being, I suspect you will get a lot of wear if you do not align within a short period, and make sure the alignment tech knows something about custom setups.

 

Im picking a spring up today and putting it in tonight.

 

I just installed the Rancho QuickLift shocks on mine to level out the front. They also have the Rancho 9 way adjustment on them which is awesome for differnet driving conditions! If you are changing your springs anyway and want to level out your ride I highly recommend them, and you don't need a front end alignment afterwards

 

As tooldad said, always change front or rear springs in pairs. Most likely the spring broke from defective manufacturing practices or bad metal to start with. Most aftermarket suppliers only sell springs in pairs. I'd be curious how you bought only one front spring, xj. My guess would be dealership parts department, but that's only a guess.

 

I got a new ford spring from the dealership to replace the other old one i have. We will see how it goes, from what i priced, the dealership was around the same price as all the parts store, but they just happened to have on in stock both times i got one.