Part of the data ring
RunCost
Logbook · Subcompact Cars · 2001–2020

Roush Performance Stage 3 Mustang

What it costs to keep fuelled

$3,310a year, fuel only

The 2020 Roush Performance Stage 3 Mustang is EPA-rated at 14.5 MPG combined (12.5 city / 19 highway). Over 15,000 miles a year that is about 1034 gallons, $3310 a year in fuel, or $0.221 per mile at $3.20/gal.

Across its full 2001–2020 run it averages 16.7 MPG, falling by 3.5 MPG over 18 model years.

LOGBOOK ENTRY · 2020 ROUSH PERFORMANCE STAGE 3 MUSTANG SHEET ROUSH-PERFORMANCE-STAGE-3-MUSTANG · 18 YEARS ON FILE
14.5 MPG COMBINED 0 60

The band is how far one gallon carries it: 14.5 of the 60 MPG this scale runs to. The square tick is the subcompact cars average, 24.2.

Fuel, per year
$3,310 at 15,000 mi
Per mile
$0.221
Per kilometre
$0.137
Gallons burned/yr
1034

1 mile = 1.609344 km · fuel at $3.20/gal, fixed JUL 2026

Test figure — not a road result

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

Combined14.5MPG · 2020
Cost per mile$0.221at $3.20/gal
Fuel per year$331015,000 miles
Class rank220of 229

How this is worked out

  1. Start from the EPA combined figure for the model year — a laboratory test cycle run to a fixed procedure, not a road result. Where a year sold several engines or drivetrains, the trims are averaged and the trim count is printed beside the row so you can see how much averaging is behind it.
  2. Fix a pump price. This site keeps one reference price, $3.20 a US gallon, fixed JUL 2026 and printed next to every dollar figure it produces. It is an assumption with a date on it, not a quote — put your own price in.
  3. Fix an annual distance. Every annual figure on this site uses 15,000 miles a year, roughly the US average. A cost per year with no stated distance is not a number, it is a mood.
  4. Divide distance by economy for gallons, multiply by price for the year's fuel, divide price by economy for one mile. The per-kilometre line is that last figure divided by 1.609344 — the same money, in the unit most of the world drives in.
  5. Stop there. No depreciation, no tyres, no insurance, no servicing. This is the fuel line of the ledger and it is labelled as one; depreciation usually dwarfs everything on it.
gallons/yr = miles/yr ÷ MPG
fuel  $/yr = gallons/yr × $/gal
cost  $/mi = $/gal ÷ MPG
cost  $/km = cost $/mi ÷ 1.609344

The full method, the licence note, and what a test figure cannot tell you →

Re-run the ledger at another pump price

Every line above rests on one pump price. Here is the same entry re-costed at six others, because the price is the part that changes while the test sheet stays put.

Fuel pricePer mile10,000 mi/yr15,000 mi/yr20,000 mi/yr
$2.50/gal $0.172 $1724 $2586 $3448
$3.00/gal $0.207 $2069 $3103 $4138
$3.20/gal $0.221 $2207 $3310 $4414
$3.50/gal $0.241 $2414 $3621 $4828
$4.00/gal $0.276 $2759 $4138 $5517
$4.50/gal $0.310 $3103 $4655 $6207
$5.00/gal $0.345 $3448 $5172 $6897

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

The whole service history, sheet by sheet

18 model years on file. Read down the combined column: a nameplate that got heavier shows it here long before any brochure admits it.

Every model year of the Roush Performance Stage 3 Mustang the EPA has a test sheet for, averaged across trims.EPA DATA · JUL 2026
YearCombinedCityHighwayEPA fuel cost/yrCO₂ g/miTrims
2020 14.5 MPG12.519 $53255942
2019 15 MPG12.519.5 $51505852
2017 16.5 MPG13.522.5 $46755452
2016 16.5 MPG13.523 $46755522
2015 16 MPG1323 $48005602
2014 17 MPG14.522 $45505182
2013 17.5 MPG1522.5 $44255092
2012 17 MPG14.521.5 $45505252
2011 16 MPG1421 $48005551
2010 17.5 MPG14.522 $44255082
2009 16.5 MPG14.520 $46755392
2008 16.5 MPG14.520 $46755392
2007 16 MPG1420 $48005551
2006 16 MPG1420 $48005551
2004 18 MPG1523 $43004941
2003 17.5 MPG1522 $44255082
2002 18 MPG15.522 $43004942
2001 18 MPG15.522 $43004942

Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

Marked against the rest of the subcompact cars bay

Among the 229 subcompact cars models tracked here, the Roush Performance Stage 3 Mustang ranks 220 on current figures, against a class average of 24.2 MPG — the square tick on the gauge above.

Closest more-efficient alternatives in the same class: BMW 850ci (15), Audi S4 Cabriolet (15.5), BMW M3 Coupe (16), Ford Shelby GT350 Mustang (16), Maserati GranTurismo (16).

Tailpipe CO₂ is rated at 594 grams per mile, which works out to roughly 8.9 tonnes a year at 15,000 miles.

Questions asked across the counter

What MPG does the Roush Performance Stage 3 Mustang get?

The 2020 Roush Performance Stage 3 Mustang is rated at 14.5 MPG combined by the EPA — 12.5 city and 19 highway. Across all 18 model years in the database it averages 16.7 MPG, ranging from 14 to 18 depending on year and trim.

How much does a Roush Performance Stage 3 Mustang cost in fuel per year?

At 14.5 MPG and 15,000 miles a year, it burns about 1034 gallons — roughly $3310 a year with fuel at $3.20 a gallon, or $0.221 per mile. The EPA's own published annual figure for the 2020 model is $5325.

Has the Roush Performance Stage 3 Mustang become more efficient over time?

No — it has actually gone backwards, from 18 MPG in 2001 to 14.5 in 2020. That usually reflects the model growing heavier, more powerful, or moving upmarket rather than the engineering getting worse.

Is the Roush Performance Stage 3 Mustang efficient for its class?

It ranks 220 of 229 in the Subcompact Cars class on current figures, against a class average of 24.2 MPG. That is 9.7 worse than typical for the class.

SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026

Cost per mile, per kilometre and per year are computed at a reference price of $3.20 a gallon over 15,000 miles, fixed JUL 2026 — set your own pump price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.

See all 10 sites in this family, with what each one answers

Published by

Amit Sharma

Auckland real-estate agent and marketer. Builds free, sourced data tools.