4" Sentinel Exhaust Brakes - Description

Both the Standard and Heavy Duty 4" Sentinel Exhaust Brake are a high-output, all-electric exhaust braking system engineered to convert up to 80% of engine output into retarding force, delivering industry-leading braking performance for towing and heavy use. By eliminating air systems, vacuum components, and complex plumbing, Sentinel’s electric actuation provides fast, consistent braking with fewer failure points. This is why our durable, simplified design is backed by a true lifetime warranty. 

Both Standard and Heavy Duty Sentinel Brakes requires no ECM or TCM programming, installs in about one hour with basic hand tools, and is guaranteed to fit a diesel vehicles with 4" exhaust systems.

Choose the Right Sentinel Exhaust Brake for Your Truck

Feature	Standard	Heavy Duty
Best For (4”)	Stock turbo & fueling	Performance tuning, heavy towing
Braking Power	Max exhaust braking	Max exhaust braking
Recommended Use	Heavy standard/recreational towing	Heavy towing, commercial use
Automation	Fully automated (Manual option)	Fully automated (Manual option)
Installation	1–3 hours	1–3 hours
Air System Required	No	No
Warranty	Lifetime	Lifetime
Price	$1398.00	$1650.00

Not sure which to choose?

If your diesel vehicle is equipped with a performance turbo, upgraded injectors, or used for heavy or commercial towing, we recommend the Heavy Duty option. For stock trucks used for daily driving or recreational towing, the Standard option delivers excellent exhaust braking performance.

🟩 Buy Standard
🟩 Buy Heavy Duty

Need help confirming fitment?
Contact Bundy Motors: 435-704-2272
Mon–Fri 6AM–6PM • Most Saturdays

How Fitment Works

Sentinel universal exhaust brakes are sized by exhaust pipe diameter, not by vehicle make or model.

To select the correct size:

• Measure the outside diameter of your exhaust pipe at the desired installation location

• Choose the matching Sentinel exhaust brake size (2.5", 3", 3.5", 4", 4.5", or 5")

This sizing method allows Sentinel exhaust brakes to be used on a wide range of diesel engines and platforms, including pickups, vans, box trucks, buses, industrial engines, and custom applications.

Core Features (Same Across All Sentinel Exhaust Brakes)

All Sentinel 2.5"–5" exhaust brakes include the same core features found in vehicle-specific Sentinel systems:

• Electric inline exhaust brake — no air system required

• Fully automated operation, opening and closing with throttle input

• No ECM or TCM programming required

• Durable gear-reduced electric motor

• Simple installation using basic tools

• Compatible with mechanical and electronically controlled diesel engines

• Backed by a lifetime warranty

Sentinel exhaust brakes are designed to operate independently of factory systems, making them well-suited for both stock and modified vehicles.

Performance & Safety Benefits

Sentinel exhaust brakes help:

• Improve downhill safety and speed control

• Reduce reliance on service brakes

• Minimize brake fade caused by overheating

• Support safer towing and hauling

• Increase driver confidence on long descents

By using engine braking instead of relying solely on wheel brakes, Sentinel helps maintain more consistent and predictable braking performance under load.

Ideal Applications

The 2.5"–5" Sentinel Exhaust Brakes are commonly used on:

• Diesel pickup trucks

• Commercial trucks and fleet vehicles

• Vans and shuttle buses

• Box trucks and delivery vehicles

• Industrial engines (including Cummins 4BT)

• Custom builds and engine swaps

If your diesel vehicle has a compatible exhaust diameter and sufficient clearance for inline installation, a Sentinel exhaust brake can likely be installed.

Installation Overview

Installation typically includes:

1. Mounting the exhaust brake inline with the exhaust system

2. Routing wiring

3. Connecting the Sentinel controller

Because Sentinel operates automatically, it provides consistent exhaust braking support without requiring constant driver input.

Warranty & Durability

Sentinel exhaust brakes are built to withstand:

• High exhaust temperatures

• Heavy towing loads

• Long downhill grades

• Continuous real-world diesel use

Every Sentinel exhaust brake is backed by a lifetime warranty.

Fitment Support

If you’re unsure which size to choose or need help confirming installation clearance, Bundy Motors is available to assist before or after purchase.

Call - Mon-Fri, Most Saturdays: 435-704-2272