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How do I accout for a rear pumkin swap, going from 3.15 to 3.55, as it applies to speedo/odometer readings?
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3.15 to 3.55 rear diff swap - Speedo correction??
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Ebm
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If your car isn't tuned, I believe you can do it via Forscan.
Is your car tuned? If so, use the tuning device.
If your car isn't tuned, I believe you can do it via Forscan.
JohnVallo
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Speedo correction??
Shouldn't need to do anything for a Gear Change concerning speedo correction.
The wheel speed sensor picks up the rotation at the half shafts (axle).
If you change tire size, that is a different story.
I've swapped several 2016 Mustang Rear Ends (Gears), and the speedo remained accurate.
Shouldn't need to do anything for a Gear Change concerning speedo correction.
The wheel speed sensor picks up the rotation at the half shafts (axle).
If you change tire size, that is a different story.
I've swapped several 2016 Mustang Rear Ends (Gears), and the speedo remained accurate.
09jsw
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I used my whipple flare to change from 3.73 to 3.31
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ctandc72
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Tuning device (normal handheld) doesn't do anything to change gear ratio on S550. You can select it - but it doesn't actually do anything. Gear ratio isn't stored in the ECU.
I went from 3.15 to 3.55 - no changes - speedo verified accurate with GPS.
I changed in it FORScan (because I was already in there) - no change, speedo stayed the same. The wheel sensors pick up wheel rotation and I'm guessing have a certain "range" they can work in.
Flare tool (Whipple), FORScan, and HPTuners can all change the gear ration in the BCM where it resides in the S550.
OP
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My car is an auto. But, the pinion flange is easy to swap out in order to make a diff that came out of an auto car work with a manual tranny.
Mine has barely 3,000 miles on it. I'd let it go cheap if you are interested.
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OP
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Thanks guys. I'm not changing tire size, so it sounds like I'm good-to-go!
pike1346
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How do you like the new 3.55's. I have an auto with 3.15, and want to swap too. I was thinking 3.31, but how do you like the 3.55. Does it feel like it has more low end torque?
white15gt
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If you have a manual transmission you will need to change the gear ratio in the computers. Whipple's tool and the FPP power packs can do it. Not sure of anybody else. If you don't, the car will go into clutch protect mode and take away all throttle input for approx 30 seconds.
ctandc72
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huh? I swapped from 3.15 to 3.55 with zero changes (manual transmission) zero issues, speedo dead on GPS Verified before and after swap. The difference in gears is picked up by the ABS wheel / speed sensors.
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