Automotive DIY

Use the free tire diameter calculator below to find the overall height of any P-metric or LT/flotation tire in seconds. Enter a size like 225/55R17 or 33x12.50R20 (or fill in the three fields manually) and instantly get the overall diameter, sidewall height, circumference, and revolutions per mile and per kilometer in both inches and millimeters. Need to swap sizes? Use the built-in comparison tool to see the difference between two tires side by side, including speedometer error percentage.

Car and truck oil drain plug sizes can be confusing, especially if you slide under your vehicle ready for an oil change and realize you have no idea which socket you need. Plug sizes vary between makes, models, and engines, and even different years of the same vehicle can use different drain bolts. The good news is that most manufacturers reuse the same sizes across multiple engines and model years, so once you know what your vehicle takes, the job gets much easier every time.

Quick answer: The most common oil drain plug sizes are 13 mm, 14 mm, 15 mm, 17 mm, and 19 mm. Use the lookup tool below to find the exact size for your vehicle, or scan the reference chart further down this page.

Check Car Value by VIN (Free Tools to Get Accurate Market Value Instantly). Find out what a car is worth, compare pricing, and confidently negotiate a fair deal. Whether you're selling, trading in, buying, or just curious, you can quickly estimate a vehicle’s value using your VIN and a few basic details.

Ford VIN Decoder and Build Sheet Guide: Learn how to decode a Ford VIN and understand its factory build sheet details. If you are curious about engine, trim, production location, or options not shown on the window sticker, this guide explains it all.

Free RAM Build Sheet by VIN and RAM VIN Decoder Tools: Need detailed factory configuration data for your RAM truck or van? Use the free RAM VIN decoder and RAM build sheet lookup tools provided below to retrieve the original factory equipment list directly from manufacturer-supported records for vehicles with standardized 17-character VINs (1981 and newer).

Wondering how to read tire size numbers? The letters and numbers on your tire sidewall, like P215/65R15 95H DOT 3523, are not random. They form a standardized code that reveals your tire's width, sidewall height, construction, wheel size, load capacity, speed rating, and manufacturing date.

Jeep VIN Decoder and Build Sheet Guide: Your 17-character Vehicle Identification Number reveals where and how your Jeep was built. This complete guide explains how to decode a Jeep VIN, retrieve a factory build sheet, and find your VIN using a license plate if needed. Whether you’re verifying a used Jeep, checking specifications, or researching factory options, this guide and its free tools make it easy to access accurate, vehicle specific information.

Car Dealership Transparency: Let's be honest, buying a used car lives at the crossroads of excitement and anxiety. Customers are often walking onto the lot with a lot on the line: their savings, their trust, and their hopes that what they're told matches what they are buying, in pricing, vehicle history, and condition.

Standard and Metric Wrench Sizes and Socket Sizes | SAE to Metric Conversion | Wrench and Socket Sizes in Order: I used to have all of the SAE standard wrench and socket sizes in order memorized and could tell you instantly what size was next in order from small to large and which metric socket or wrench was equivalent. That was decades ago, back in my days as a mechanic and industrial technician.

Stock Challenger RT Auto Dyno Results, HP and Torque Numbers. After breaking in my new Dodge Challenger RT 5.7 Hemi, I decided to test its stock horse power and torque on a Dynojet. For reference, a 2009 Dodge Challenger RT with an automatic transmission is rated at 372 HP and 400 FT LBs of Torque from the factory.