Should I fix my car or buy a new one? A free calculator from a Denver shop.

Then this calculator is the wrong tool. It can only tell you the financial answer. If you've fallen out of love with a vehicle, that's a valid reason to replace it — just go in with eyes open about what it'll cost.

A common rule says that if a single repair costs more than 50% of the car's market value, you should consider replacement. The better question is cost-per-remaining-mile. If the repair plus expected ongoing maintenance costs less per mile than a replacement vehicle's monthly payment plus insurance, fixing is almost always the right call.

Expected lifespan depends heavily on the brand. Toyota, Honda, and Lexus regularly reach 250,000 to 300,000 miles with proper maintenance. Most mainstream brands reach 200,000 to 250,000 miles. European luxury vehicles often last 150,000 to 200,000 miles before repair costs exceed value.

In most cases repairing is cheaper. The average new car payment is over $700 per month and a used car payment is around $525. Even a $3,000 repair that gets you two more years of service costs about $125 a month, far less than any replacement. Repair becomes the wrong choice when the car is at end-of-life, has safety problems, or repair bills are stacking up monthly.

Kelley Blue Book (kbb.com) and Edmunds both provide free vehicle value estimates. Use the private-party value if you would sell it yourself, or the trade-in value if you would trade it at a dealership. Trade-in is typically 15-25% lower than private-party value.

Almost always yes, if the rest of the vehicle is sound. A $3,000 transmission repair on a vehicle worth $8,000 or more usually saves you $20,000+ over buying a comparable replacement. The exception is when the car has other major issues, frame damage, or is approaching the end of its expected lifespan. The math heavily favors repair when remaining lifespan exceeds 50,000 miles.

A professional rebuild is almost always the better long-term value. Rebuilds replace every wear part with new components and typically come with a warranty of 12-36 months. Used transmissions are cheaper upfront but carry no warranty and unknown wear. Remanufactured transmissions are between the two — factory-rebuilt with warranty but more expensive than a local rebuild.

Get a written estimate that itemizes parts and labor separately. Cross-check the part prices against rockauto.com or the dealer parts counter. Labor hours should match published flat-rate guides (Mitchell or AllData). For major repairs, a free second opinion from another shop is the easiest way to verify. At Don's Garage in Denver we offer free second-opinion reviews of any repair quote.

Repairs that exceed the vehicle's value AND involve structural problems are usually not worth it. Examples: frame damage on a 15-year-old daily driver, a blown engine in a vehicle with a failing transmission and 250,000+ miles, or major rust through structural body panels. Single-system repairs on otherwise sound cars almost always pencil out.

With consistent oil changes, fluid services, and prompt attention to small problems, modern vehicles routinely reach 200,000-300,000 miles. The biggest factor is preventing small issues from becoming catastrophic ones — a $200 cooling system flush prevents a $4,000 engine. Regular maintenance is the cheapest insurance there is.

Most domestic and Japanese transmissions rebuild for $2,200-$4,000 depending on complexity and parts. European and high-performance transmissions can run $4,000-$6,000+. Beware of quotes significantly below this range — they often skip critical wear components. At Don's Garage in Denver we provide itemized estimates that show exactly what's being replaced.

If your current car has fewer than 200,000 miles and the repair is under 50% of its value, fixing is almost always the better financial choice. New car ownership averages over $11,000/year between depreciation, insurance, and payments. A repaired car costs only the repair plus regular maintenance. Use this calculator with your specific numbers to see your real cost-per-mile comparison.

Don's Garage Automotive and Transmission at 5515 Washington Street in Denver offers free second-opinion reviews of repair quotes from other shops. Family-owned since 1970, we'll tell you whether the quoted work is necessary, whether the price is fair, and whether there's a more affordable approach. Call (303) 295-2448.