4.10's in our 18 GT's

Has anyone done this yet. I know about less gas mileage and short shifting 1 st. gear but I put 4.10's in my 2004 Mach1 and absolutely loved it. My dealer is willing to install the 4.10 for me so when I take delivery it is ready to "rock 'n roll". Right now I just have the 3.55 and figure if I am going to change the rear area why not skip the 3.73 and have some real fun! Your thoughts please (and yes I have thick skin).

4.10 with the 4.6 and 5 speeds was great. I would NOT want anything shorter than the 3.73 in the coyote cars with 6 speeds. Maybe the new MT82 ratios are different enough in the 18 to make it make sense but I doubt it.

2018 MT-82 D4:
3.24
2.10
1.42
1.00
0.81
0.62

2011-2017 MT-82:
3.66
2.43
1.69
1.32
1.00
0.65

Also keep in mind, you will need a custom tune as well when you change out the gears in an S550.

Thanks to each of you for the good info and things I had not thought of. My dealer did tell me he would have to change the computer software to change gearing so the speedometer would be correct. However the revised gear ratios of the revised '18 M-82 is a major issue and probably means the lowest gear I could enjoy using is the 3.73 . With that said I don' think spending around $900 to go from 3.55 to 3.73 is very good value. I can certainly better spend my hard earned money.

Yes it would probably be fun and work well with the new ratios especially if staying NA. Could always do 3.91 that US gear makes if you didn't want to go with the 4.09 from Ford performance.

I have 4.10s and get better mileage in the city than stock. You can cruise in town in 5th. It sits at 2k rpm at 60 mph. Absolute rocket ship when you take off though. They are fun, but a little annoying in traffic. But hey, that's a manual anyway. Just my experience. If you are staying N/A, 3.73 or 4.10 will be fun.

Ebm said:

I have 4.10s and get better mileage in the city than stock. You can cruise in town in 5th. It sits at 2k rpm at 60 mph.

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Which transmission are you talking about here? 2k in 5th gear is not going to get you 60mph with either the previous MT-82 nor the '18 version unless you have 33" tires. Maybe you mean 2k in 6th gear at 60mph?

.

Grimace427 said:

Which transmission are you talking about here? 2k in 5th gear is not going to get you 60mph with either the previous MT-82 nor the '18 version unless you have 33" tires. Maybe you mean 2k in 6th gear at 60mph?

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Yes, sorry about that. My words kind of jumbled together. 2k rpm in 6th gear at 60 mph.

Gotcha.

white15gt said:

Also keep in mind, you will need a custom tune as well when you change out the gears in an S550.

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No tune needed - only a small change in BCM. It can be done with Forscan - free of charge.

On the other hand Forscan will not work properly with a locked tune like Lund.

strongholdsteve said:

No tune needed - only a small change in BCM. It can be done with Forscan - free of charge.

On the other hand Forscan will not work properly with a locked tune like Lund.

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You sure that works on a manual car? Because the gears are stored in two places, and when there is a delta, the car goes into clutch protect mode.

From S550 the ratio is taken from BCM not like in S197 from ECU. You can still switch it back on in S550's ECU should you need to.

Stock tune will work with ratio up to 3,73. 4,09 requires a change in BCM.

strongholdsteve said:

No tune needed - only a small change in BCM. It can be done with Forscan - free of charge.

On the other hand Forscan will not work properly with a locked tune like Lund.

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The newest firmware for Lund's nGAUGE adds gear ratio/tire size adjustability.

If my maff is right, a 2018 6MT with a 4.09 is still less first gear than a 2017 with a 3.73:

2017
1st 3.66 x 3.73 = 13.65

2018
1st 3.24 x 4.09 = 13.25