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Tensioner Belt 3978022 3922900 3937553 for Cummins 6CT 6BT 4BT 4BTA 8.3L Engine
$60.99
Sale price
$60.99
Regular price
Available to Order
Designed for select Cummins diesel engines and compatible equipment, this aftermarket automatic belt tensioner helps restore proper accessory-belt tension and tracking.
Not sure which part fits your equipment?
Our Northline Parts team can help you find the right replacement. Support Hours: Monday–Friday, 8:00 AM–5:00 PM CT | Live Chat: Available 24/7
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Product Overview
The belt tensioner maintains the pressure needed to keep the accessory belt seated on the pulleys. Bearing noise, arm play, weak spring force, or belt flutter can indicate a worn tensioner.
Replacement references include 3978022, 3922900, 3937553. Compare the part number, pulley diameter and width, mounting position, arm offset, and belt layout before ordering.
Key Features & Performance
- Helps reduce belt slip, flutter, and misalignment
- Replaces a worn pulley bearing or weak tensioner assembly
- Designed for compatible Cummins engine applications
- Supports dependable accessory drive operation
Fitment & Compatibility
Compatible with Cummins 4BT, 4BTA, 6BT, and 6CT engine applications, including select 8.3L configurations. Serial-number breaks, production changes, or equipment options may affect the required part.
Technical Specifications
- Product Type: Automatic Belt Tensioner
- Compatible Brand: Cummins
- Part Number(s): 3978022, 3922900, 3937553
Frequently Asked Questions
Q: Should the belt be replaced with the tensioner? A: Inspect the belt and all idler pulleys for glazing, cracking, wear, or noise. Replacing worn related components together can prevent repeat failure.
Q: Is this an original OEM part? A: This is a high-quality aftermarket replacement and is not supplied by the original equipment manufacturer.
Serial-number breaks and production changes may affect fitment. Verify the original part before purchase.