(According to Wikipedia, coil springs are commonly used in vehicle suspension. Coil springs in trucks allow them to ride smoothly when unloaded and once loaded the spring compresses and becomes stiff. This allows the vehicle to bounce less when loaded. Image source: How Stuff Works)
We decided to go out for lunch and since there were just 3 of us from the office, we decided to take my car instead of the usual ride – my buddy’s more robust and heavy-duty Toyota Unser. Just when I drive away from the parking lot, I heard a “thud, thud, thud” sound coming from the wheelbase. My friends heard it too.
At first, we thought we had a tyre punctured so my friend got down and had a quick inspection. The tyre looked good, so we decided to drive on. The sound was still there so I decided to drive slower. I was more worried that the sound may be coming out from wheel bearing (a problem that I faced in the past) or worst, the whole tyre coming out loose.
We had our lunch which was great, made a pit stop at the “number” shop to do some “investments” and drove back to the office. This time, the sound was not that loud but still audible.
I was not feeling too comfortable – any strange sound means something is wrong with the car and I am a hardcore phobia of unnecessary sound from the car. My friends tried to make things less dramatic by saying that the sound was due to the heavyweight passengers.
Later in the evening when I was leaving the office, I still had an unsettled feeling about the sound. I started the car and as I drive off, to my surprise, the sound was still there. So, having heavyweight passengers was not the cause of it.
I knew I need to take the car to the workshop to check on the sound first thing in the morning but first of all, I need to get back home in one piece. To make matters worse, there were a heavy thunderstorm couple of hours before that and that caused a massive traffic jam on LDP.
So, with a “noisy” car and hardly moving traffic, I was on the highway, imagining the worst-case scenarios – tyre flying off and make the traffic jam even worst. All I wanted to do is to reach the house first – so I opted to take the old road to reach home. I can drive slower and in case anything; there is less traffic on the road.
I managed to reach home without any problems and the first thing I did is to rise up the car and check on the sound. I immediately found the source – the wheel weight hitting against the handbrake cable.
The cable must have gotten loose when the heavyweight passengers got into the car. And why that happened is because the existing spring is unable to take the load causing the body to get too low and hit the brake cables.
The lowering of the spring must have also been affected by all that moving of household things in the past when we used the car as items mover and over the years, it must have gotten lower.
The shock absorbers in my car are rather new but coil springs are not – there is an unsettled concern when I drive over minor potholes and carry extra passengers.
With Monroe shocks at the front and rear, I know the problem is not the shocks. It may be due to the mods done to fit the disc brakes but all fingers seem to be pointing to the original, worn-out coil springs.
Checking over the internet does not really give me the right time to change the coil springs. According to my cousin, coil springs should be changed every 5 years (it depends on the driving style as well).
Hope to get the coil springs replaced by end of this week – hmm, perhaps I should get the whole suspension system inspected too. Another improvement for aged my car and hope to get a better riding feeling next week (and can take heavyweight passengers too).