Wabco 4757110030 Automatic Load Sensing Valve

Description

The Wabco 4757110030 is an Automatic Load Sensing Valve, a critical component in air brake systems for trailers. It dynamically regulates the air pressure to the trailer brakes based on the load, ensuring optimal braking performance and stability. This valve is used in the trailer brake control system to prevent wheel lockup and maintain vehicle control, especially under varying load conditions. Its pneumatic design and dynamic operation contribute to a more responsive and efficient braking system. The valve measures 121 x 200 x 311 mm and features M16 x 1.5 port threads. It’s designed to OE specification with a regulating ratio of 1:8, a maximum operating pressure of 13.0 bar, and a temperature range of -40°C to +80°C. The distance between mounting bolts is 84x84 mm, and it features a flap exhaust.

Key Features & Benefits

This valve basically figures out how much weight is in your trailer, and then adjusts the air pressure going to the trailer brakes accordingly. It does this with a mechanical linkage – usually a rod that runs from the trailer’s spring suspension up to the valve. As the trailer gets heavier, the springs compress, and that movement tells the valve to send more air to the trailer brakes. It's a purely mechanical system, no electronics involved. It’s a key part of your trailer brake control system. Think of it like this: the tractor protection valve sets the maximum air pressure going to the trailer brakes, but this valve fine – tunes it based on how much load you're carrying. Without it, your trailer brakes might be too weak when fully loaded, or way too strong when empty – creating a safety hazard and wearing out your brakes prematurely. It ensures proportional braking, meaning the trailer brakes apply with the right amount of force for the weight it’s carrying.

Symptoms, Risks & Replacements

It's absolutely vital for safe and effective trailer braking. You'll notice if this valve goes bad, because your trailer’s braking will feel off – either not strong enough to stop reliably when loaded, or grabbing and skidding when empty. It prevents trailer sway, reduces stopping distances, and generally keeps you much safer on the road. It’s one of those things you don’t think about when it’s working right, but you’ll definitely know if it isn’t. If you're looking to replace one, you can find a good selection over at Fixparts Online, but any reputable truck parts supplier will carry them. Just make sure you get the right one for your setup.

Warranty Information

Wabco Automatic Load Sensing Valve (MPN 4757110030) comes with a 1-year warranty.