https://youtu.be/Mrwul3s7RDo
I wanted to share my experience so far with the 5 Star Tune for the 2015 Jayco Precept 29UM Ford F53 6.8L V10 5 speed transmission. I have 19,600 miles in less than 2 years of ownership, all utilizing the stock setup. Overall, I have been happy with the Jayco's ride, handling, and drive-ability, rating it a 9/10. However, like most Ford motorhome owners, I have been less than impressed with the engine and transmission. While I felt the power was good, the engine mannerism and transmission shifting patterns were frenetic and unrefined. At the first sign of a hill, the sluggish engine would overslow, followed by at least 2 upshifts, or worse, the dreaded 3 upshifts into 2nd gear, resulting in a cacophony of high pitched wails in the cockpit. I had subconsciously learned to hit the "RES" to deactivate the cruise control and take control of the gas pedal to prevent it. Regardless, the drivetrain refused to respond quickly to my accelerator inputs, delaying the upshift which led to loss of momentum. If I got too overzealous, the Ford would punish me with those 3 downshifts. Rating: 3.5/10
After the easy and fast 15 minute installation of the 5 Star Tuning X4 map tonight, I took the Jayco for a 12 mile test ride. Immediately, the motor seemed to idle smoother and quieter. It simply felt peppier right out of the parking lot. The shifts were much smoother and faster. Accelerating onto the interstate was impressive, feeling much livelier and spritely under demand. Rating: 9/10
If you are considering upgrading to a newer 2016+ to get the 6 speed F53, consider this option instead. I read another report from a 2016 F53 owner and former 2015 owner who felt the 5 Star tune made his older 5 speed perform as well as his 2016 6 speed.
Linear Mode
