I just got done yesterday changing my stock 3.55 gear to a 4.30, myself, and it was definitely worth the hard work. The change itself wasnt too hard but I would definitely not suggest doing yourself unless you have the special tools needed. I would strongly recommend that if you do do it yourself, to drop the whole rear end out of the car. It makes it so much easier if you dont have a lift..... to tighten the pinion preload and shim the carrier. All total it took about two full nights after work to complete. I plan on posting a how to on how to change it yourself. I plan on track testing her tonight since if have two race, tonight night and sat. night. I cant believe the lack of parts for this car currently!!! I accidently install one of the brake pads backwards and scored the rotor, which is ONLY availible through Ford.. Shiming the carrier was by far the hardest part, maybe not hard, but time consuming. As for noise, under acceleration (drive) it has no noise, while in coast it has a slight whine but I think it may be b/c of such a large step in gear sizes. ie 3.55-4.30. The change really didnt hurt the top end that much either. At 70 mph in 5 gear its running at 2800rpm which is about a 1000 rpm higher. All in all I am happy with! Would I do it again.....? Probally now that ive done it before. Well if anyone has any question feel free to let me know. Also, a special thanks to my local Ford dealership, for loaning me their only copy of the "05 Mustang Bible" (-Ford dealer service manual), during the change
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05 Mustang GT, Windveil Blue, 5 speed Manual, Mickey Thompson ET Street tires, SCT XCal Tuner, JEGS Line Locks, FRP 4.30 gear, C&L True CAI, Hooker Long tube headers, 12.70 1/4 mile ET, w/ 1.70 60'
I just got done yesterday changing my stock 3.55 gear to a 4.30, myself, and it was definitely worth the hard work. The change itself wasnt too hard but I would definitely not suggest doing yourself unless you have the special tools needed. I would strongly recommend that if you do do it yourself, to drop the whole rear end out of the car. It makes it so much easier if you dont have a lift..... to tighten the pinion preload and shim the carrier. All total it took about two full nights after work to complete. I plan on posting a how to on how to change it yourself. I plan on track testing her tonight since if have two race, tonight night and sat. night. I cant believe the lack of parts for this car currently!!! I accidently install one of the brake pads backwards and scored the rotor, which is ONLY availible through Ford.. Shiming the carrier was by far the hardest part, maybe not hard, but time consuming. As for noise, under acceleration (drive) it has no noise, while in coast it has a slight whine but I think it may be b/c of such a large step in gear sizes. ie 3.55-4.30. The change really didnt hurt the top end that much either. At 70 mph in 5 gear its running at 2800rpm which is about a 1000 rpm higher. All in all I am happy with! Would I do it again.....? Probally now that ive done it before. Well if anyone has any question feel free to let me know. Also, a special thanks to my local Ford dealership, for loaning me their only copy of the "05 Mustang Bible" (-Ford dealer service manual), during the change
Hey nautiluscont,
You must be young to tackle that job w/ no lift You mentioned the whine on decel. I had 4.10's put in and have that also, but no shims were used. The shop said they'd shim it anytime if I'm not happy. I happened to be on the phone w/ Steeda and the tech mentioned a 3rd link to change the pinion angle. It can help w/ wheel hop and whine also…I was told. I guess you're not going to "grandma" your gears for 500 miles. My shop said no need to change the synthetic fluid till around 30K either. Ford tech said pretty much the same thing. It's your choice of filling w/ regular gera oil for 500 and then put in the synt. good luck and nice post!
I just got done yesterday changing my stock 3.55 gear to a 4.30, myself, and it was definitely worth the hard work. The change itself wasnt too hard but I would definitely not suggest doing yourself unless you have the special tools needed. I would strongly recommend that if you do do it yourself, to drop the whole rear end out of the car. It makes it so much easier if you dont have a lift..... to tighten the pinion preload and shim the carrier. All total it took about two full nights after work to complete. I plan on posting a how to on how to change it yourself. I plan on track testing her tonight since if have two race, tonight night and sat. night. I cant believe the lack of parts for this car currently!!! I accidently install one of the brake pads backwards and scored the rotor, which is ONLY availible through Ford.. Shiming the carrier was by far the hardest part, maybe not hard, but time consuming. As for noise, under acceleration (drive) it has no noise, while in coast it has a slight whine but I think it may be b/c of such a large step in gear sizes. ie 3.55-4.30. The change really didnt hurt the top end that much either. At 70 mph in 5 gear its running at 2800rpm which is about a 1000 rpm higher. All in all I am happy with! Would I do it again.....? Probally now that ive done it before. Well if anyone has any question feel free to let me know. Also, a special thanks to my local Ford dealership, for loaning me their only copy of the "05 Mustang Bible" (-Ford dealer service manual), during the change
Hey nautiluscont,
You must be young to tackle that job w/ no lift You mentioned the whine on decel. I had 4.10's put in and have that also, but no shims were used. The shop said they'd shim it anytime if I'm not happy. I happened to be on the phone w/ Steeda and the tech mentioned a 3rd link to change the pinion angle. It can help w/ wheel hop and whine also…I was told. I guess you're not going to "grandma" your gears for 500 miles. My shop said no need to change the synthetic fluid till around 30K either. Ford tech said pretty much the same thing. It's your choice of filling w/ regular gera oil for 500 and then put in the synt. good luck and nice post!
1000 RPMs higher with 4.30's really isn't bad. I am thinking of going with 4.10's. Anyone know what RPMs you run around 70mph with those? I am hearing about 2500.
I would assume that the rpms @ 70 in 5th should be less than with a 4.30. Yesterday after running it for a while, the whine is not nearly as noticeable, but maybe that was b/c the grinding from install the brake pad wrong was overwelming j/k anyways, I used synthetic from the start with the fiction additive. That is what the ford dealer service manual said the use from the start. Its not cheap either! 3 quart + 3oz? of additive @ tech price (10% above cost) was $54.00 +. The stuff must be like gold! BTW, After changing the gear I realized Im definitely not as young as I used to be.... Im 24 now!
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05 Mustang GT, Windveil Blue, 5 speed Manual, Mickey Thompson ET Street tires, SCT XCal Tuner, JEGS Line Locks, FRP 4.30 gear, C&L True CAI, Hooker Long tube headers, 12.70 1/4 mile ET, w/ 1.70 60'
1000 RPMs higher with 4.30's really isn't bad. I am thinking of going with 4.10's. Anyone know what RPMs you run around 70mph with those? I am hearing about 2500.
1000 RPMs higher with 4.30's really isn't bad. I am thinking of going with 4.10's. Anyone know what RPMs you run around 70mph with those? I am hearing about 2500.
2500 rpm's @ 70mph w/ OD on 2500 rpm's @ 45mph w/ OD off.
Man, that thing is gonna really scream down that track. Will you have to use 5th gear? I'm guessing with cool temps you should be able break into the 12s. Be sure to let us know how it runs, and be carefull.
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DHG #01434 Bullitt - full JLT intake, MGW shifter, Accel coils (I wish I had 4.10s, o/r H, tune)
Black 89 LX(the drag car) best 8.75 at 80 mph in the 1/8
97 Mountaineer V8 AWD
4.30 Gear Install 
. Shiming the carrier was by far the hardest part, maybe not hard, but time consuming. As for noise, under acceleration (drive) it has no noise, while in coast it has a slight whine but I think it may be b/c of such a large step in gear sizes. ie 3.55-4.30. The change really didnt hurt the top end that much either. At 70 mph in 5 gear its running at 2800rpm which is about a 1000 rpm higher. All in all I am happy with! Would I do it again.....? Probally now that ive done it before. Well if anyone has any question feel free to let me know. Also, a special thanks to my local Ford dealership, for loaning me their only copy of the "05 Mustang Bible" (-Ford dealer service manual), during the change 
You mentioned the whine on decel. I had 4.10's put in and have that also, but no shims were used. The shop said they'd shim it anytime if I'm not happy. I happened to be on the phone w/ Steeda and the tech mentioned a 3rd link to change the pinion angle. It can help w/ wheel hop and whine also…I was told. I guess you're not going to "grandma" your gears for 500 miles. My shop said no need to change the synthetic fluid till around 30K either. Ford tech said pretty much the same thing. It's your choice of filling w/ regular gera oil for 500 and then put in the synt. good luck and nice post!
