| 11.1.2015 | Daytona Test | 8 | #24 | van der Zande / Schultis / Popow / Hedlund / Bernoldi | Starworks Motorsport | 16th |
| 11.1.2015 | Daytona Test | 11 | #34 | Cumming / Hawksworth / Junqueira / Menezes | RSR Racing | 14th |
| 11.1.2015 | Daytona Test | 16 | #11 | Mowlem / Papadopoulos / Drissi / Alder | BAR1 Motorsports | 18th |
| 11.1.2015 | Daytona Test | 38 | #4 | French / Mee / Vautier | Performance Tech Motorsports | 23rd |
| 11.1.2015 | Daytona Test | 52 | #39 | Guasch / Novich / Palmer / Kimber-Smith | PR1 Mathiasen Motorsports | 21st |
| 11.1.2015 | Daytona Test | 54 | #20 | Bennett / Braun / Wilkins / Gue | Core Autosport | 13th |
| 11.1.2015 | Daytona Test | 54T | #12 | Bennett / Braun / Wilkins / Gue | Core Autosport | T-car |
| 11.1.2015 | Daytona Test | 61 | #22 | Plowman / Drumwright / Ducote / Ware | BAR1 Motorsports | 20th |
| 11.1.2015 | Daytona Test | 85 | #21 | Goikhberg / Simpson / Mitchell | JDC/Miller Motorsports | 22nd |
| 25.1.2015 | 24 h Daytona | 8 | #24 | van der Zande / Schultis / Popow / Hedlund / Albuquerque | Starworks Motorsport | 43rd |
| 25.1.2015 | 24 h Daytona | 11 | #34 | Cumming / Hawksworth / Junqueira / Menezes | RSR Racing | 34th |
| 25.1.2015 | 24 h Daytona | 16 | #11 | Mowlem / Papadopoulos / Drissi / Alder / Plowman | BAR1 Motorsports | 53rd |
| 25.1.2015 | 24 h Daytona | 38 | #4 | French / Mee / Vance / Johnston | Performance Tech Motorsports | 44th |
| 25.1.2015 | 24 h Daytona | 52 | #39 | Kimber-Smith / Guasch / Novich / Palmer | PR1/Mathiasen Motorsports | 8th |
| 25.1.2015 | 24 h Daytona | 54 | #12 | Braun / Bennett / Wilkins / Gue | Core Autosport | 10th |
| 25.1.2015 | 24 h Daytona | 61 | #22 | Plowman / Drumwright / Breukers / Blackstock / Ruscitti | BAR1 Motorsports | 40th |
| 25.1.2015 | 24 h Daytona | 85 | #21 | Simpson / Goikhberg / Miller / Vautier / Mitchell | JDC/Miller Motorsports | 15th |
| 21.3.2015 | 12 h Sebring | 8 | #24 | Popow / van der Zande / Schultis | Starworks Motorsport | 30th |
| 21.3.2015 | 12 h Sebring | 11 | #34 | Cumming / Junqueira / Menezes | RSR Racing | 31st |
| 21.3.2015 | 12 h Sebring | 16 | #11 | Plowman / Drumwright / Drissi / Cheng | BAR1 Motorsports | 34th |
| 21.3.2015 | 12 h Sebring | 38 | #4 | Daly / Mee / French | Performance Tech Motorsports | 9th |
| 21.3.2015 | 12 h Sebring | 52 | #39 | Kimber-Smith / Guasch / Palmer | PR1/Mathiasen Motorsports | 6th |
| 21.3.2015 | 12 h Sebring | 54 | #12 | Braun / Bennett / Gue | Core Autosport | 7th |
| 21.3.2015 | 12 h Sebring | 85 | #21 | Mitchell / Goikhberg / Miller / Kraut | JDC/Miller Motorsports | 29th |
| 3.5.2015 | 2 h Laguna Seca | 8 | #24 | Schultis / van der Zande | Starworks Motorsport | 20th |
| 3.5.2015 | 2 h Laguna Seca | 11 | #34 | Cumming / Junqueira | RSR Racing | 6th |
| 3.5.2015 | 2 h Laguna Seca | 16 | #11 | Slusher / Falb | BAR1 Motorsports | 19th |
| 3.5.2015 | 2 h Laguna Seca | 38 | #4 | French / Hedlund | Performance Tech Motorsports | 10th |
| 3.5.2015 | 2 h Laguna Seca | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 33rd |
| 3.5.2015 | 2 h Laguna Seca | 54 | #12 | Bennett / Braun | Core Autosport | 8th |
| 3.5.2015 | 2 h Laguna Seca | 85 | #21 | Goikhberg / Veach | JDC/Miller Motorsports | 16th |
| 30.5.2015 | 100 min Detroit | 8 | #24 | Schultis / van der Zande | Starworks Motorsport | 6th |
| 30.5.2015 | 100 min Detroit | 11 | #34 | Cumming / Junqueira | RSR Racing | 21st |
| 30.5.2015 | 100 min Detroit | 16 | #11 | | BAR1 Motorsports | DNA |
| 30.5.2015 | 100 min Detroit | 38 | #4 | French / Vance | Performance Tech Motorsports | 10th |
| 30.5.2015 | 100 min Detroit | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 22nd |
| 30.5.2015 | 100 min Detroit | 54 | #13 | Bennett / Braun | Core Autosport | 19th |
| 30.5.2015 | 100 min Detroit | 85 | #21 | Goikhberg / Simpson | JDC/Miller Motorsports | 9th |
| 28.6.2015 | 6 h Watkins Glen | 8 | #24 | Hedlund / van der Zande / Popow | Starworks Motorsport | 4th |
| 28.6.2015 | 6 h Watkins Glen | 11 | #34 | Cumming / Junqueira | RSR Racing | 30th |
| 28.6.2015 | 6 h Watkins Glen | 16 | #11 | Burkett / McMurry / Plowman | BAR1 Motorsports | 6th |
| 28.6.2015 | 6 h Watkins Glen | 38 | #4 | Daly / French / Mee | Performance Tech Motorsports | 31st |
| 28.6.2015 | 6 h Watkins Glen | 52 | #39 | Guasch / Kimber-Smith / Palmer | PR1/Mathiasen Motorsports | 5th |
| 28.6.2015 | 6 h Watkins Glen | 54 | #13 | Bennett / Braun / Gue | Core Autosport | 7th |
| 28.6.2015 | 6 h Watkins Glen | 85 | #21 | Goikhberg / Mitchell / Miller | JDC/Miller Motorsports | 9th |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 8 | #24 | Schultis / van der Zande | Starworks Motorsport | 22nd |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 11 | #34 | Cumming / Junqueira | RSR Racing | 16th |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 16 | #11 | Falb / Rayhall | BAR1 Motorsports | 10th |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 38 | #4 | French / Daly | Performance Tech Motorsports | 23rd |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 20th |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 54 | #13 | Bennett / Braun | Core Autosport | 8th |
| 12.7.2015 | 2 h 40 min Mosport [P/PC/GTLM] | 85 | #21 | McMurry / Goikhberg | JDC/Miller Motorsports | 11th |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 8 | #24 | Schultis / van der Zande | Starworks Motorsport | 3rd |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 11 | #34 | Cumming / Junqueira | RSR Racing | 2nd |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 16 | #11 | Slusher / Rayhall | BAR1 Motorsports | 5th |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 38 | #4 | French / Daly | Performance Tech Motorsports | 16th |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 1st |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 54 | #13 | Bennett / Braun | Core Autosport | 4th |
| 25.7.2015 | 2 h Lime Rock [PC/GTD] | 85 | #21 | Simpson / Goikhberg | JDC/Miller Motorsports | 6th |
| 9.8.2015 | 2 h 40 min Road America | 8 | #24 | Schultis / van der Zande | Starworks Motorsport | 31st |
| 9.8.2015 | 2 h 40 min Road America | 11 | #34 | Cumming / Junqueira | RSR Racing | 7th |
| 9.8.2015 | 2 h 40 min Road America | 16 | #22 | McMurry / Burkett | BAR1 Motorsports | 12th |
| 9.8.2015 | 2 h 40 min Road America | 38 | #4 | French / Daly | Performance Tech Motorsports | 8th |
| 9.8.2015 | 2 h 40 min Road America | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 10th |
| 9.8.2015 | 2 h 40 min Road America | 54 | #13 | Bennett / Braun | Core Autosport | 9th |
| 9.8.2015 | 2 h 40 min Road America | 85 | #21 | Miller / Goikhberg | JDC/Miller Motorsports | 32nd |
| 19.9.2015 | 2 h 40 min Austin | 8 | #24 | Hedlund / van der Zande | Starworks Motorsport | 21st |
| 19.9.2015 | 2 h 40 min Austin | 11 | #34 | Cumming / Junqueira | RSR Racing | 7th |
| 19.9.2015 | 2 h 40 min Austin | 16 | #11 | Slusher / Falb | BAR1 Motorsports | DNS |
| 19.9.2015 | 2 h 40 min Austin | 38 | #4 | French / Daly | Performance Tech Motorsports | 8th |
| 19.9.2015 | 2 h 40 min Austin | 52 | #39 | Guasch / Kimber-Smith | PR1/Mathiasen Motorsports | 9th |
| 19.9.2015 | 2 h 40 min Austin | 54 | #13 | Bennett / Braun | Core Autosport | 6th |
| 19.9.2015 | 2 h 40 min Austin | 61 | #22 | Yount / Lewis | BAR1 Motorsports | 35th |
| 19.9.2015 | 2 h 40 min Austin | 85 | #21 | McMurry / Goikhberg | JDC/Miller Motorsports | 14th |
| 19.9.2015 | 2 h 40 min Austin | 88 | #18 | Popow / Rayhall | Starworks Motorsport | DNS |