by VIN, Year, Make, Model by License Plate

2003 Mitsubishi Diamante Overview, Reviews, Ratings & Specs

Rating: 4.80
Based on 12 Owner Reviews â–¶
Simon A | March 31, 2025
The 2003 Mitsubishi Diamante is a full-size sedan offering a blend of luxury and performance. Produced from 1992-2004, it aimed to provide a more upscale experience compared to other Mitsubishi offerings. Key trims for 2003 included the base and LS. The Diamante stood out with its spacious interior, powerful V6 engine, and distinctive styling. Original pricing ranged from approximately $26,000 to $30,000, making it an attractive option for budget-conscious buyers seeking a near-luxury experience.
The Good

The 2003 Diamante offers a smooth and powerful V6 engine, delivering adequate performance for daily driving. Its comfortable ride and spacious interior appeal to those seeking a relaxing experience. While not the most fuel-efficient, it offers good value for its price point, making it attractive to practical buyers. The sleek design provides a touch of luxury, appealing to those seeking a stylish sedan.

The Bad

Potential weaknesses of the 2003 Diamante include its relatively poor fuel economy compared to some competitors. Some owners have reported issues with the automatic transmission, so thorough inspection is crucial. Parts availability can be a challenge due to its age and relative rarity. Rust can also be a concern in certain climates, so check carefully for any signs of corrosion.

2003 Mitsubishi Diamante: Quick Overview

Key Specs for the 2003 Mitsubishi Diamante:

  • Engine Options: 3.5L SOHC 24-valve V6
  • Horsepower: 205 hp @ 5000 rpm
  • Torque: 231 lb-ft @ 4000 rpm
  • Fuel Economy (City/Highway): Approximately 18/26 mpg (actual figures may vary)
  • 0-60 mph: Around 8.5 seconds (estimated)
  • Towing Capacity: Not recommended or officially rated.
Trim-Level Features:
  • Base Trim: Included features such as automatic climate control, power windows and locks, cruise control, AM/FM/CD stereo, and alloy wheels.
  • LS Trim: Added leather upholstery, power-adjustable driver's seat, sunroof, upgraded audio system, and sometimes included features like heated seats. Additional options could include a premium sound system and chrome accents. Both trims featured standard safety equipment including front airbags and antilock brakes (ABS). Differences between the trims mostly revolved around comfort and convenience features, rather than significant mechanical upgrades. The suspension and engine remained consistent across both models. The LS model provided a more luxurious driving experience with its upgraded interior and amenities.

2003 Mitsubishi Diamante Specifications

Vehicle Information
Year 2003
Make Mitsubishi
Model Diamante
Trim -
Style -
Type Sedan Hard Top
Category Compact Car
Manufacturing Details
Made In Australia
Manufacturing City TONSLEY PARK
Dimensions
Doors 4-Door
Curb Weight -
Gross Vehicle Weight Rating -
Overall Height -
Overall Length -
Overall Width -
Wheelbase Length -
Standard Seating -
Engine & Performance
Engine 6G74
Engine Size 3.5L
Engine Cylinders 6
Transmission -
Transmission Type -
Transmission Speeds -
Drivetrain Front-Wheel Drive
Additional Features
Anti-Brake System -
Steering Type -
Pricing
Manufacturer Suggested Retail Price (MSRP) -
Invoice Price -
Delivery Charges -

Vehicle History Report

Vehicle
Specifications
Ownership
History
All History
Events
NMVTIS Title
History Check
Salvage/Rebuilt
Check
Accident
Check
Theft
Check
Open Lien
Check
Past Sale
Listings
Safety
Recalls
Odometer
Check
Market Price
Analysis
View VINCheck Report

What Problems Does the 2003 Mitsubishi Diamante Have?

Frequently reported problems for the 2003 Mitsubishi Diamante often revolve around the automatic transmission. Some owners have experienced slipping or rough shifting, particularly at higher mileage. It's essential to check the transmission fluid regularly and address any issues promptly. Another area of concern can be the electrical system, with reports of sensor failures and occasional issues with the climate control system. Rust, as with many vehicles of this age, is a potential issue, particularly in areas with harsh winters and road salt. Inspect the undercarriage, rocker panels, and wheel wells for any signs of corrosion.

While specific recalls for the 2003 model may exist, it's crucial to check the National Highway Traffic Safety Administration (NHTSA) website for the most up-to-date recall information. General long-term reliability concerns stem from the vehicle's age and potential for wear and tear on various components. Regular maintenance, including oil changes, fluid checks, and timely replacement of worn parts, is crucial for maximizing its lifespan. Parts availability can sometimes be a challenge, as the Diamante was not a high-volume seller in the US market. Pre-purchase inspections by a qualified mechanic are highly recommended.

How long will the 2003 Mitsubishi Diamante last?

With diligent maintenance, a 2003 Mitsubishi Diamante can potentially reach 200,000 miles or more. However, average mileage varies greatly depending on owner care. Expect to see many examples with 150,000 to 250,000 miles. Long-term durability largely depends on preventative maintenance. Weaknesses often emerge in the form of worn suspension components (struts, bushings), transmission issues, and the gradual degradation of rubber and plastic parts. Rust is a major concern, particularly in colder climates. Keeping up with fluid changes and addressing minor issues promptly can significantly extend the vehicle's lifespan. Examples with complete service records are highly desirable.

What Technology & Safety Features are Included?

The 2003 Mitsubishi Diamante, by today's standards, features relatively basic technology. Standard entertainment included an AM/FM radio with a CD player. Higher trims offered upgraded sound systems. There were no advanced driver-assistance features available. Safety features consisted primarily of front airbags and anti-lock brakes (ABS), which were standard. Optional features included a sunroof and leather upholstery.

Regarding crash test ratings, information for the 2003 Mitsubishi Diamante is somewhat limited. It's recommended to consult the Insurance Institute for Highway Safety (IIHS) and the National Highway Traffic Safety Administration (NHTSA) websites for specific crash test data. Keep in mind that safety standards and testing methodologies have evolved significantly since 2003, so comparing its crashworthiness to modern vehicles may not be entirely relevant. It lacked modern features like side airbags, electronic stability control, and advanced braking systems. Therefore, while adequate for its time, its safety technology is dated compared to contemporary vehicles.

What Colors Options are Available?

Exterior Colors
Alpine Silver Metallic
Black Onyx
Laguna Blue Metallic
Siberian White
Sunset Red Metallic
Interior Colors
Charcoal Black
Sand Beige

2003 Mitsubishi Diamante Prices and Market Value

When new, the 2003 Mitsubishi Diamante ranged from approximately $26,000 to $30,000 depending on the trim and options. Current used market prices typically range from $2,000 to $5,000, depending on condition, mileage, and location. The Diamante has experienced significant depreciation due to its age, brand reputation, and the availability of newer, more fuel-efficient, and technologically advanced vehicles. Factors affecting resale value include overall condition, maintenance history, mileage, and the presence of any significant mechanical or cosmetic issues. Examples in excellent condition with low mileage and complete service records will command a premium.

2003 Mitsubishi Diamante Cost of Ownership

The 2003 Mitsubishi Diamante is not particularly economical to own. Insurance costs are moderate, but fuel economy is relatively poor. Maintenance and repair costs can be higher than average due to potential parts availability issues and the age of the vehicle. Expect to budget for potential repairs to the transmission, suspension, and electrical systems. Long-term ownership costs can add up quickly, especially if the vehicle has not been well-maintained. Budgeting for unexpected repairs is crucial.

2003 Mitsubishi Diamante Fuel Efficiency

Fuel Type Gasoline
Fuel Capacity -
City Mileage -
Highway Mileage -

2003 Mitsubishi Diamante Safety Rating

NHTSA
Overall Rating Not Tested
Overall Frontal Star Rating Not Tested
Side Overall Star Rating Not Tested
Overall Rollover Star Rating Not Tested
Combined Front Seat Rating Not Tested
Combined Rear Seat Rating Not Tested
Overall Frontal Star Rating Not Tested
Frontal Barrier Star Ratings Not Tested
Side Barrier Star Ratings Not Tested
Rollover Resistance Star Rating Not Tested

2003 Mitsubishi Diamante Recalls & Defects

Equipment:other:owners/Service/Other Manual
Recall date 2004-02-11
Recall no. 04v067000
Source NHTSA
Summary Certain Sport Utility and Passenger Vehicles Fail TO Comply With Federal Motor Vehicle Safety Standard NO. 225, "child Restraint Anchorage Systems." THE Owner's Manual Does NOT Contain A Step-By-Step Description FOR Headrest Adjustment When Installing A Child Restraint System (Crs) Tether Strap.
Consequence IF THE Tether Strap IS Improperly Installed TO THE Tether Anchor, THE Child Safety Seat MAY NOT BE Sufficient Restrained. IN THE Event OF A Crash, THE Child Could BE Injured.
Remedy A Letter Outlining THE Problem Will BE Sent TO Owners Along With A Sticker Containing THE Correct Instructions AS Well AS Instructions ON Where TO Affix THE Sticker IN THE Owner's Manual. THE Recall Began ON March 29, 2004. Owners Should Contact Mitsubishi AT 1-888-648-7820.
Notes Mitsubishi Recall NO. Sr-04-002.customers CAN Also Contact THE National Highway Traffic Safety Administration's Auto Safety Hotline AT 1-888-dash-2-dot (1-888-327-4236).
Equipment:other:labels
Recall date 2004-09-01
Recall no. 04v428000
Source NHTSA
Summary Certain Passenger Vehicles Fail TO Conform TO THE Requirements OF Federal Motor Vehicle Safety Standard NO. 208, 'occupant Crash Protection.' THE Bilingual English/Spanish Removable AIR BAG Warning Labels Affixed TO THE Dash and TO THE Sunvisor DO NOT Meet THE Size Requirements OF THE Standard.
Consequence This Does NOT Meet THE Requirements OF THE Standard.
Remedy Mitsubishi Caribbean Will Mail A Customer Notification Letter Containing A Written Description and A Graphic OF THE Bi-Lingual Dashboard AIR BAG Warning Label. IN Addition, All Current 2000-2004 Nativa Owners Will Also Receive Replacement AIR BAG Alert Labels FOR THE SUN Visors. This Recall IS Expected TO Begin During March or April 2005. THE Notification TO THE Nativa Owners IS Expected TO Begin During April or MAY 2005. Owners Should Contact Mitsubishi Caribbean AT 1-787-251-8715.
Notes THE Manufacturer's Petition Which Requested That Nhtsa Determine This Fmvss Noncompliance Does NOT Create AN Unreasonable Risk TO Motor Vehicle Safety WAS Partially Denied ON January 26, 2005. Therefore, This Manufacturer IS Obligated TO Conduct AN Owner Notification and Remedy Campaign.customers CAN Also Contact THE National Highway Traffic Safety Administration's Auto Safety Hotline AT 1-888-327-4236.

2003 Mitsubishi Diamante Insurance

Insurance for a 2003 Mitsubishi Diamante is moderately priced, reflecting its status as a Sedan Hard Top with strong safety ratings and
reasonable repair costs.

How Does the 2003 Mitsubishi Diamante Compare to Other Sedan Hard Top?

The 2003 Mitsubishi Diamante competed with vehicles like the Toyota Avalon, Nissan Maxima, and Buick LeSabre. Compared to the Avalon and Maxima, the Diamante offered similar performance but lagged behind in terms of reliability and resale value. The LeSabre offered comparable comfort but lacked the Diamante's sporty styling. In terms of features, the Diamante was generally well-equipped for its time but lacked the advanced technology found in some competitors.

If reliability is a primary concern, the Toyota Avalon is a significantly better choice. The Nissan Maxima offers a sportier driving experience with comparable reliability. The Buick LeSabre provides a more comfortable and traditional full-size sedan experience. While the Diamante may be a tempting option due to its lower price, the potential for higher maintenance costs and lower reliability makes the alternatives generally more sensible purchases. Consider a well-maintained Avalon or Maxima from the same era for a more reliable and enjoyable ownership experience. These alternatives generally have better parts availability and a stronger track record for long-term durability.

Ranks #2015 Sedan

1 2023 Toyota Camry (5.0★)
2 2023 Honda Accord (0.0★)
3 2023 Lexus ES (0.0★)
4 2024 Subaru Legacy (5.0★)
5 2022 Mazda MX-30 (4.0★)
6 2024 BMW M3 (0.0★)
7 2023 Ford Mustang (5.0★)
8 2023 Mercedes-Benz AMG GT (0.0★)
9 2023 Audi A3 (0.0★)
10 2023 Chevrolet Camaro (5.0★)
11 2023 Hyundai Elantra Hybrid (0.0★)
12 2023 Nissan Altima (4.0★)
2015 2003 Mitsubishi Diamante (4.0★)

Final Verdict: Is the 2003 Mitsubishi Diamante a Good Sedan Hard Top?

The 2003 Mitsubishi Diamante is ideal for budget-conscious buyers seeking a comfortable, full-size sedan with a touch of luxury. It's worth buying *only* if it's in exceptionally good condition, has a documented maintenance history, and is priced accordingly. A pre-purchase inspection by a trusted mechanic is essential. Look for examples with low mileage and minimal rust. Given its age and potential reliability concerns, it's generally not recommended unless you're prepared for potential repairs and maintenance. Newer, more reliable alternatives, like the Toyota Avalon or Nissan Maxima, are generally better choices, even if they cost slightly more upfront. The LS trim offers slightly more features but isn't necessarily worth a significant price premium.

2003 Mitsubishi Diamante Owner Reviews

4.80
Consumer Rating, Based on 12 Consumer Reviews
Overall rating
Cancel
Thank You for Your Review!

We truly appreciate the time and effort you took to share your experience with us.

Uh oh!

Something went wrong, please try again later.

The Fud on October 19, 2017

Reliable Luxury Car w/o Luxury Price

This car has met all my family's needs for 14 years. From my Dad, to my sister to myself, we have gently used this car in town and over the highways. Stylist, spacious, very comfortable ride for 5 adult passengers. Good on gas for a V6 with a huge trunk for lots of luggage. A/C & heat work like a charm!

Was this review helpful?
1
0

JSchnider on September 23, 2011

Very reliable luxurious car.

This was certainly a very reliable car and was very luxurious as well. The LS model comes fully loaded with leather seating, alloy wheels, moonroof, heated seats, fog lights, premium stereo and many extras.

Was this review helpful?
1
0

Bergy76 on April 6, 2010

Owned 1 since 2004 never had a problem!!

I have owned this vehicle since 2004, going from a 1995 Cadillac xxx. I feel that this vehicle had just about the same bells and whistles except for the often break downs of my Cadillac. I bought it with 19k miles on it. I have only replaced the door speakers and two O2 sensors. Other than normal wear and tear stuff.. I wish they still made this car. I do know I will continue to buy Mitsubushi brand vehicles in the future!!

Was this review helpful?
1
0

lawman on August 23, 2006

rocket on wheels

Great fun to drive. Be careful not to get too many speeding tickets! Great value that poeple don't know about. If they were more common the price would be much higher. Built in Australia for the out back, very reliable.

Was this review helpful?
1
0

The Fud on October 19, 2017

Reliable Luxury Car w/o Luxury Price

This car has met all my family's needs for 14 years. From my Dad, to my sister to myself, we have gently used this car in town and over the highways. Stylist, spacious, very comfortable ride for 5 adult passengers. Good on gas for a V6 with a huge trunk for lots of luggage. A/C & heat work like a charm!

Was this review helpful?
1
0

JSchnider on September 23, 2011

Very reliable luxurious car.

This was certainly a very reliable car and was very luxurious as well. The LS model comes fully loaded with leather seating, alloy wheels, moonroof, heated seats, fog lights, premium stereo and many extras.

Was this review helpful?
1
0

Bergy76 on April 6, 2010

Owned 1 since 2004 never had a problem!!

I have owned this vehicle since 2004, going from a 1995 Cadillac xxx. I feel that this vehicle had just about the same bells and whistles except for the often break downs of my Cadillac. I bought it with 19k miles on it. I have only replaced the door speakers and two O2 sensors. Other than normal wear and tear stuff.. I wish they still made this car. I do know I will continue to buy Mitsubushi brand vehicles in the future!!

Was this review helpful?
1
0

lawman on August 23, 2006

rocket on wheels

Great fun to drive. Be careful not to get too many speeding tickets! Great value that poeple don't know about. If they were more common the price would be much higher. Built in Australia for the out back, very reliable.

Was this review helpful?
1
0

The Fud on October 19, 2017

Reliable Luxury Car w/o Luxury Price

This car has met all my family's needs for 14 years. From my Dad, to my sister to myself, we have gently used this car in town and over the highways. Stylist, spacious, very comfortable ride for 5 adult passengers. Good on gas for a V6 with a huge trunk for lots of luggage. A/C & heat work like a charm!

Was this review helpful?
1
0

JSchnider on September 23, 2011

Very reliable luxurious car.

This was certainly a very reliable car and was very luxurious as well. The LS model comes fully loaded with leather seating, alloy wheels, moonroof, heated seats, fog lights, premium stereo and many extras.

Was this review helpful?
1
0
Author Image
Simon A

Simon is a contributor to VinCheck, where he provides articles and reviews on various automotive topics. His work focuses on delivering accurate and up-to-date information about used cars, helping readers make informed decisions.