Roadmax 3K390AP Serpentine Belt - Fan and Alternator

Roadmax 3K390AP Serpentine Belt Overview

The Roadmax 3K390AP is an automotive V-ribbed belt in the standard line, built for drivers who want a practical replacement belt with quality materials. It uses EPDM construction and a polyester cord for dependable accessory drive performance in the fan and alternator drive on select Toyota Corolla applications.

Roadmax’s Automotive V-Ribbed Belt (Standard) line focuses on everyday replacement needs, offering a balanced option for budget-conscious maintenance without moving into premium belt performance levels. The 3K390AP follows the K cross-section profile and 3-rib design used in the accessory drive belt system.

Key Features

• Part number: 3K390AP
• Automotive V-ribbed belt, standard line
• EPDM belt material for durable belt construction
• Polyester cord material for reinforcement
• 3-rib design with K cross section
• Top width: 11 mm (.42 in.)
• Effective length: 994 mm (39.13 in.)
• Outside circumference: 1006 mm (39.625 in.)
• Compatible with fan and alternator drive applications on select Toyota Corolla models

Application Details

This serpentine belt is used in accessory drive belt system components and is listed for 1987 Toyota Corolla, fan and alternator, as well as 1983-1986 Toyota Corolla, fan and alternator, with A/C noted as not equipped on those earlier applications. If you are searching for a Toyota Corolla serpentine belt, Toyota Corolla accessory drive belt, or Roadmax 3K390AP replacement belt, this part matches the specified fitment and dimensions.

This part cross-references Gates K030390 and Dayco 5030390 for the same application.

What It Helps Address

• Squealing or slipping accessory drive belt noise
• Cracking, glazing, or visible wear on the belt surface
• Loss of belt tension affecting fan and alternator operation
• Replacement needs for a worn Toyota Corolla serpentine belt
• Routine maintenance on the accessory drive belt system

Installation Notes

Verify belt routing, rib count, and measured length before installation. Confirm the vehicle’s accessory drive layout matches the listed Toyota Corolla fitment, including fan and alternator position and the A/C note for 1983-1986 models. Inspect pulleys, tensioner condition, and alignment before installing the new belt to help prevent premature wear.

Quality Assurance

Roadmax positions the Automotive V-Ribbed Belt (Standard) line as a practical replacement choice for customers who want quality materials in a standard-duty belt. The EPDM construction and polyester cord support consistent service in the accessory drive system when matched to the correct application.