Thinking about 4:10s Need some advice

[jprez1980]

Hey Gang---

Anyone know what the stock gearing is in a 03 GT with a 5 speed tranny? I am thinking about putting in 4:10's and would like to know what to expect. I drive a lot of highway miles and am worried about higher revving in 5th. Also what kind of pricing to expect for parts and install in the Dallas area?

Thanks!
JP

 

[Cobra Jay]

THe stock gear ratio is 3.27. 4.10's are o.k. for use on the e-way, but if you plan on installing a S/C someday, go with a 3.73 insted. If you're worried about RPM's, go here and click on CALCULATORS www.differentials.com. You'll be able to see what your engine will be turning at specific MPH in 5th gear. Use .67 for the trans ratio. This will help you make your decision.

 

[scalder]

I had 4.10's for a few months and running 75+ all day long was no big deal. Now the 4.30's on the other hand.....

 

[GTvert01]

No problem with the 4.10s and the hwy.I get 23-24mpg @ 70+mph.

 

[jrc_03_gt]

get 4.10"s ! I just got mine put in last week.

 

[jprez1980]

Cool thanks guys...how much are the parts and where in the Dallas area can I get them installed?

Thanks!

 

[scalder]

Well I had my 4.10's installed at Dallas Mustang..when my axles gave up I had 4.30's, axles, etc done at Lonestar Performance. Their pricing is a little better and they aren't complete arse's like DMP.

 

[moreause]

THe stock gear ratio is 3.27. 4.10's are o.k. for use on the e-way, but if you plan on installing a S/C someday, go with a 3.73 insted. If you're worried about RPM's, go here and click on CALCULATORS www.differentials.com. You'll be able to see what your engine will be turning at specific MPH in 5th gear. Use .67 for the trans ratio. This will help you make your decision.

Can somebody tell me if there is a difference between the us and the canada i always see 0.67 for fifth that was t-45 it's 0.68 for tremec but mine is 0.62 and i check with a friend and it is the same. So i don't know if usa as a shorter fifth or what???

 

[Cobra Jay]

Can somebody tell me if there is a difference between the us and the canada i always see 0.67 for fifth that was t-45 it's 0.68 for tremec but mine is 0.62 and i check with a friend and it is the same. So i don't know if usa as a shorter fifth or what???

Not sure there is a difference.


According to these 2 links the 04's are .68 and the 03's are .67
I was also told by the dealer, .67 for mine.

www.mustangmeet.com/specs/2003.php
www.mustangmeet.com/specs/2004.php

They could be wrong though. If you notice they show 3.55's for both the 04 GT's and the MACH1's 5spds. and and 2.49's for the auto's which is in accurate.

 

[moreause]

ok then is't going to be numbers then i used to run 2000 rpm at 120kph/74.4 mph with 3.27 and now i'm running 2250 at 120kph/74.4mph with 3.73 that is what i get with 0.62...i check all rpm and number in excel to make sure every thing was right.

so if you have a minute give me your speed vs rpm to make sure

 

[Joel's98GT]

Overdrive in a t-3650 is .62 it has always came with this ratio

3.27 is the ONLY gear option on 99+ GT's from the factory

 

[Cobra Jay]

ok then is't going to be numbers then i used to run 2000 rpm at 120kph/74.4 mph with 3.27 and now i'm running 2250 at 120kph/74.4mph with 3.73 that is what i get with 0.62...i check all rpm and number in excel to make sure every thing was right.

so if you have a minute give me your speed vs rpm to make sure

I'm just about to leave work, so I'll hit the e-way get up to 75 (or more )then let you know later on or tomorrow.

 

[jrc_03_gt]

I have an 03 gt at 90mph I tack around 3000 RPM"S in 5th gear. I have frpp 4.10"s.

 

[Cobra Jay]

At 75mph I was at 2000. Must be a .62 o.d. Looks like I was given some bad info. That's cool though. With 4.10's at 75 I'll only be turning 2502. 80=2669 85=2836. Sweet!