3.73 to 4.88 Gear Swap Problems **RESOLVED, STEEDA TUNE FIXED ALL ISSUES**

[ice445]

A Ford GT350 TR3160 or another Tremec XL model, the second involves substantially more work. I believe that the GT and GT350 use the same reverse and temp sensor and it plugs right in. No custom driveshaft, mount, or shifter, direct Ford for Ford parts swap.

Problem is that 2019 and up cars have auto rev matching which is done with a hardware change to the transmission, involving a hall effect sensor and harness that tells the computer what gear the car is in, which is information it HAS to have. So the only way to defeat this is if the Mach1 has the same plug and same sensor in the Tremec. But even then it will likely prove problematic since the Tremec will certainly have different gear ratios.

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[GreenS550]

Problem is that 2019 and up cars have auto rev matching which is done with a hardware change to the transmission, involving a hall effect sensor and harness that tells the computer what gear the car is in, which is information it HAS to have. So the only way to defeat this is if the Mach1 has the same plug and same sensor in the Tremec. But even then it will likely prove problematic since the Tremec will certainly have different gear ratios.

If you've been reading this, the OP fixed the problem including rev matching with a Steeda tune.

FTIW, you still need a tune on the 17 and down cars to get them to run correctly with a gear change. I know this because I swapped differentials and the car did not run correctly. I got a tune and it was fixed. Since then I've ordered a Forscan tool and will change the car to stock, change the gearing with Forscan to have it run correctly without a tune

I am guessing Ford built in different gear changes in the Mach I like the 17 down. But maybe not up to 488. I know they have a 410 in the computer as I have seen it.

 

[Fly2High]

If you put a 4.10 in the car, does it still need a tune?

I have a PP2 which has smaller diameter tires which effectively increases the final drive ratio. The stock 3.73 acts like a 3.94 gear. If I put the 4.10 (which, I think will act like a 4.3 - ish gear), will I need a tune?

all the best with your 4.88

 

[GreenS550]

If you put a 4.10 in the car, does it still need a tune?

I have a PP2 which has smaller diameter tires which effectively increases the final drive ratio. The stock 3.73 acts like a 3.94 gear. If I put the 4.10 (which, I think will act like a 4.3 - ish gear), will I need a tune?

all the best with your 4.88

Forscan will go up to 4.10

 

[M.A.N.]

Don't think there's any issues if your not changing it in a Bullitt.

That's all I've had issures with, or heard others say.

 

[L0566Bullitt]

Forscan will go up to 4.10

4.09*

 

[GreenS550]

4.09*

I know 409 gears are made by Ford performance but my forescan says 410

 

[Norm Peterson]

I know 409 gears are made by Ford performance but my forescan says 410

Not enough difference to matter . . .


Norm