Hey all...I'm trying to find something definitive on gear ratios for the 2006 GT with the TR-3650 (3.55:1) transmission.

1st 3.38:1
2nd 2.00:1
3rd 1.32:1
4th 1.00:1
5th 0.68:1/0.62:1
Reverse 3.38:1
Final drive 3.55:1

From what I've read so far, the standard ratio for 5th gear is either 0.68 or 0.62 with the Tremec. I guess what I'm asking is there any way to find out for sure? Even the Tremec site has different ratios for different TR-3650 part numbers.

Secondly, what's the 5th gear ratio with 4.10 gears? Would the 5th gear ratio be 0.68 or 0.62, or would it be possible to use a 0.62 ratio for 5th? The reason I'm asking Is I do about 60% highway mileage, but still wanna have plenty fun with the other 40%. Additionally, I'm in the UK and gas here is $6.00 a gallon.

 

<div class='quotetop'>QUOTE(ninetyeightstang @ February 23, 2006, 7:42 PM) Quoted post</div><div class='quotemain'>
Hey all...I'm trying to find something definitive on gear ratios for the 2006 GT with the TR-3650 (3.55:1) transmission.

1st 3.38:1
2nd 2.00:1
3rd 1.32:1
4th 1.00:1
5th 0.68:1/0.62:1
Reverse 3.38:1
Final drive 3.55:1

From what I've read so far, the standard ratio for 5th gear is either 0.68 or 0.62 with the Tremec. I guess what I'm asking is there any way to find out for sure? Even the Tremec site has different ratios for different TR-3650 part numbers.

Secondly, what's the 5th gear ratio with 4.10 gears? Would the 5th gear ratio be 0.68 or 0.62, or would it be possible to use a 0.62 ratio for 5th? The reason I'm asking Is I do about 60% highway mileage, but still wanna have plenty fun with the other 40%. Additionally, I'm in the UK and gas here is $6.00 a gallon.
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While im not sure about the 2006, i believe the 2005 mustang came with following trans ratios:

1st 3.34:1
2nd 2.00:1
3rd 1.32:1
4th 1.00:1
5th 0.67:1
Reverse- I dont know
Final drive 3.55:1

anyone who has an 2005 please correct me if im wrong.

that said, you would probably be better off if a moderator moved this post to the 2005-2008 section. it would get more traffic from the guys who know the cars better.

 

<div class='quotetop'>QUOTE(ninetyeightstang @ February 23, 2006, 7:42 PM) Quoted post</div><div class='quotemain'>
Hey all...I'm trying to find something definitive on gear ratios for the 2006 GT with the TR-3650 (3.55:1) transmission.

1st 3.38:1
2nd 2.00:1
3rd 1.32:1
4th 1.00:1
5th 0.68:1/0.62:1
Reverse 3.38:1
Final drive 3.55:1

From what I've read so far, the standard ratio for 5th gear is either 0.68 or 0.62 with the Tremec. I guess what I'm asking is there any way to find out for sure? Even the Tremec site has different ratios for different TR-3650 part numbers.

Secondly, what's the 5th gear ratio with 4.10 gears? Would the 5th gear ratio be 0.68 or 0.62, or would it be possible to use a 0.62 ratio for 5th? The reason I'm asking Is I do about 60% highway mileage, but still wanna have plenty fun with the other 40%. Additionally, I'm in the UK and gas here is $6.00 a gallon.
[/b][/quote]

I don't know what the ratio is but when you go down to 4:10 gears, it makes the 5th gear closer to the old 4th. (i.e. closer to the 1 to 1) I didn't do the math but I'd guess @ 0.75:1

 

I'd imagine the 05 is the same as the 06. My Specifications guide says:

TR3650 (GT Manual)
1st: 3.38
2nd: 2.00
3rd: 1.32
4th: 1.00
5th: 0.675
Rev: 3.38
Rear: 3.55

T5 (V6 Manual)
1st: 3.75
2nd: 2.19
3rd: 1.41
4th: 1.00
5th: 0.72
Rev: 3.53
Rear: 3.31

5R55S (Automatic)
1st: 3.22
2nd: 2.29
3rd: 1.54
4th: 1.00
5th: 0.71
Rev: 3.07
Rear: 3.31