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How do I know if trailer tire went flat?


I recently bought a cheap utility trailer. I am trying to tow it properly and learn all about it before doing it.

Is there sign that a trailer tire has gone flat? It would be obvious by looking at the rear view mirror and find one side lower than the other, but I don’t check the mirror constantly. So, how do I know?

Also, for tandem wheel trailers, wouldn’t it be almost impossible to know?

How dangerous is it when a trailer tire goes flat?

You could just use a tire pressure gauge…

You should get in the practice of using your mirrors when towing. Loads can shift and cause dangerous conditions, like trailer sway.

Also, when a tire goes down, you can feel the extra drag. Check you mirrors, and you’ll see the trailer swaying or shaking.

A trailer with a flat tire tends to be harder to control and is dangerous to the tow vehicle and the trailer itself. They tend to sway and shake, threatening to spill the load.

Very dangerous. The trailer will begin to pull from side to side and make it difficult to control the car. An unloaded tandem axle will remain somewhat stable but loaded it will be difficult to handle.

Great minds, Busted Knuckles… I seem to be slow on the draw these days and not nearly as informative as you. Hopefully Roger understands the situation.

With tandem axles, you notice the trailer swaying back and forth when a tire goes flat. Since the trailer is connected to the tow vehicle, you should feel something different, even with a single axle. Also, you should get in the habit of checking your mirrors more often, especially when towing. That alone will make you a safer driver. You don’t have to check them constantly. When I went to truck driving school, we were penalized on the driving test if we didn’t check the mirrors every 10 seconds or less.

Other than looking, you could install a Tire Pressure Monitoring System on the trailer.

And, no, when a tire goes flat on a tandem, you can still see it. That’s why it is good to always check the tires when traveling. You never know when you’ll pickup a nail!

And one of the problems that a tire leaking can result in is a tire failure. Some tire failures can result in considerable damage to the vehicle.

When I got a flat towing my boat with a single axle trailer I had no control problems. I felt a slight rumbling and noticed the tire had blown, pulled over and changed it.
I have my side mirrors tilted down a little as it is a wide trailer, and I monitor the wheel locations in the lane, so I would notice a tire going flat when looking at the wheels. I assume it was a blowout due to road debris, I was going at least 65 on the interstate.

Fortunately blow outs are rare. Best advice is to have a tire pressure guage and make sure the tires are inflated as per the trailer’s specs before you load it. Every time you stop for a break, at least do a walk around and inspect the tires, the hitch, and the trailer lights to make sure all is well before starting out again.

In the event of a blow out how dangerous it becomes is a function of your vehicle speed, the load in the trailer, and how fast the tire deflates. A sudden blow out can cause the trailer to sway and you’ll feel that in the tow vehicle immediately. Let off the gas and avoid hitting the brakes. Braking can make the trailer even less stable. Gently pull off to the shoulder of the road.

Often a trailer tire going flat will send a vibration that you can feel in the tow vehicle. At this point the tire will be very close to completely flat. Next, the trailer will feel squirrely and unstable compared to when the tire was OK. You might even see some smoke coming off the wheel in your side view mirror(s).

When towing I keep my speed to about 60 mph (on 70 mph interstates) and I stay in the far right lane as much as possible. In an emergency the slower speed and lane position gives me the best chance of handling it safely and avoiding a major accident.

You were very fortunate, waterboy. More often than not the load on a trailer is poorly balanced in the event of a flat. Top heavy tows often throw poorly tied boats off the trailer. It’s really a good idea to keep the tires and axle bearings, etc., well maintained to avoid a problem and lower the speed to account for the possibility.