Gears question in my 03 Mach 1

IBleedBlue · 01-04-2005, 11:03 PM

First time post. Just bought an 03 Mach 1. It has had some modifications (short throw shifter, flowmasters, K&N, etc.) but dealer assured me everything else was stock. I felt though that it did not have the stock 3.55 gears in it. All I have to compare it to though is my 95 GT which still has the stock 3.27 in it. Checked the speedo on the highway and it was 8-10 seconds slow. Any idea how I can check this out to be sure? Also have 26,000 left on warranty. If gears were swapped will it void out warranty?

Jeff Chambers · 01-06-2005, 07:51 AM

A gear swap will not void the car's overall warranty. If the swap was not done by a Ford dealership, then it will affect the warranty coverage of the rear end, but it will not affect the rest of the car's warranty.

One way you can determine the gear ratio is to jack up the rear end and rotate the wheel through a full rotation while counting how many times the pinion rotates.

Det289 · 01-06-2005, 01:44 PM

That is by far the easiest way to check gear ratio. its only a rough estimate but it will give you good idea where to start.

IBleedBlue · 01-06-2005, 08:32 PM

Thanks for the info. As soon as it gets warmer around here I'll put the rearend up and check it out. I'm guessing it has a 4.10 in it. It's a DD so that is geared a little lower than I would like. Any ideas how much difference the 3.55's would make?

blue00gt · 01-10-2005, 04:12 PM

If you do have 4.10s I'd leave 'em. All 3.55s will do is make you feel like it bogs and takes forever to get into the powerband and your mileage won't change by more than 1-2 mpg if that.

cowboy · 01-10-2005, 10:58 PM

we have just bought a 2003 mach 1, but it's all stock. we don't like the 355's that come stock, in 5th gear at 70 mph we're at 1900 rpm's. when i'm getting on the gears hard at about 6500 rpm's at shift, i go into 4th gear at 100 mph!! that's crazy. i still have one more gear to go. how big of a ticket do i want?!!! wouldn't 410's be a better choice? i want quick, not fast.

blue00gt · 01-11-2005, 03:49 PM

I would definitely recommend 4.10s or even 4.30s for an N/A 4-valve. Hell, I run 4.10s with over 400 rwhp.

blue00gt · 01-11-2005, 03:50 PM

I would definitely recommend 4.10s or even 4.30s for an N/A 4-valve. Heck, I run 4.10s with over 400 rwhp.

IBleedBlue · 01-14-2005, 11:08 PM

Cowboy, I answered your later post on the 4:10's. Lifted mine up and checked it out. Sure enough running a 4:10. It kind of lugs around town and your almost always in the powerband so it burns more gas. I wrap 2K at 60 and 2300 at 70. But when your ready to rock you can't beat that gear. Drove a stock 03 Mach 1 last night and it was like getting back into my 5.0 GT again. It's that much difference.

blue00gt · 01-17-2005, 03:35 PM

The difference in gas should only be 1-2mpg if that. It's only a 15% steeper gear than stock. Plus the TR3650 has a pretty tall 5th...

Mustang Brandon · 01-30-2005, 06:49 PM

use the analyzer at this site i think its pretty close

01-04-2005, 11:03 PM	#1
IBleedBlue Registered Member Join Date: Jan 2005 Posts: 11	Gears question in my 03 Mach 1 First time post. Just bought an 03 Mach 1. It has had some modifications (short throw shifter, flowmasters, K&N, etc.) but dealer assured me everything else was stock. I felt though that it did not have the stock 3.55 gears in it. All I have to compare it to though is my 95 GT which still has the stock 3.27 in it. Checked the speedo on the highway and it was 8-10 seconds slow. Any idea how I can check this out to be sure? Also have 26,000 left on warranty. If gears were swapped will it void out warranty?

01-06-2005, 07:51 AM	#2
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: Gears question in my 03 Mach 1 A gear swap will not void the car's overall warranty. If the swap was not done by a Ford dealership, then it will affect the warranty coverage of the rear end, but it will not affect the rest of the car's warranty. One way you can determine the gear ratio is to jack up the rear end and rotate the wheel through a full rotation while counting how many times the pinion rotates. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

01-06-2005, 01:44 PM	#3
Det289 Registered Member Join Date: Feb 2003 Location: Rio Rancho, NM Posts: 15	Re: Gears question in my 03 Mach 1 That is by far the easiest way to check gear ratio. its only a rough estimate but it will give you good idea where to start.

01-06-2005, 08:32 PM	#4
IBleedBlue Registered Member Join Date: Jan 2005 Posts: 11	Re: Gears question in my 03 Mach 1 Thanks for the info. As soon as it gets warmer around here I'll put the rearend up and check it out. I'm guessing it has a 4.10 in it. It's a DD so that is geared a little lower than I would like. Any ideas how much difference the 3.55's would make?

01-10-2005, 04:12 PM	#5
blue00gt Mustang Addict Join Date: Jan 2001 Location: McKinney, TX Posts: 1,294	Re: Gears question in my 03 Mach 1 If you do have 4.10s I'd leave 'em. All 3.55s will do is make you feel like it bogs and takes forever to get into the powerband and your mileage won't change by more than 1-2 mpg if that. __________________ Strike down the unroadworthy! 2000 GT Atl. Blue: '03 Cobra motor - 465rwhp/473rwtq, T-56 6-speed, full MM TA/PH & tubular K-member suspension, Saleen body, 17" Torq-Thrust II's, M/T ET Street radials, and lots more '94 Rio Red Cobra: All the bolt-ons, 3.73s

01-10-2005, 10:58 PM	#6
cowboy Registered Member Join Date: Jan 2005 Location: Oregon / Callif. Border Posts: 5	Re: Gears question in my 03 Mach 1 we have just bought a 2003 mach 1, but it's all stock. we don't like the 355's that come stock, in 5th gear at 70 mph we're at 1900 rpm's. when i'm getting on the gears hard at about 6500 rpm's at shift, i go into 4th gear at 100 mph!! that's crazy. i still have one more gear to go. how big of a ticket do i want?!!! wouldn't 410's be a better choice? i want quick, not fast. Last edited by cowboy; 01-11-2005 at 05:27 PM..

01-11-2005, 03:49 PM	#7
blue00gt Mustang Addict Join Date: Jan 2001 Location: McKinney, TX Posts: 1,294	Re: Gears question in my 03 Mach 1 I would definitely recommend 4.10s or even 4.30s for an N/A 4-valve. Hell, I run 4.10s with over 400 rwhp. __________________ Strike down the unroadworthy! 2000 GT Atl. Blue: '03 Cobra motor - 465rwhp/473rwtq, T-56 6-speed, full MM TA/PH & tubular K-member suspension, Saleen body, 17" Torq-Thrust II's, M/T ET Street radials, and lots more '94 Rio Red Cobra: All the bolt-ons, 3.73s

01-11-2005, 03:50 PM	#8
blue00gt Mustang Addict Join Date: Jan 2001 Location: McKinney, TX Posts: 1,294	Re: Gears question in my 03 Mach 1 I would definitely recommend 4.10s or even 4.30s for an N/A 4-valve. Heck, I run 4.10s with over 400 rwhp. __________________ Strike down the unroadworthy! 2000 GT Atl. Blue: '03 Cobra motor - 465rwhp/473rwtq, T-56 6-speed, full MM TA/PH & tubular K-member suspension, Saleen body, 17" Torq-Thrust II's, M/T ET Street radials, and lots more '94 Rio Red Cobra: All the bolt-ons, 3.73s

01-14-2005, 11:08 PM	#9
IBleedBlue Registered Member Join Date: Jan 2005 Posts: 11	Re: Gears question in my 03 Mach 1 Cowboy, I answered your later post on the 4:10's. Lifted mine up and checked it out. Sure enough running a 4:10. It kind of lugs around town and your almost always in the powerband so it burns more gas. I wrap 2K at 60 and 2300 at 70. But when your ready to rock you can't beat that gear. Drove a stock 03 Mach 1 last night and it was like getting back into my 5.0 GT again. It's that much difference. __________________ 1995 GT K & N Flowmaster 40 Series 2003 Mach 1 Ford Racing 4:10 BBK X-pipe K & N Flowmaster 50 Series Pro 5.0 Shifter Tokico Struts and Shocks

01-17-2005, 03:35 PM	#10
blue00gt Mustang Addict Join Date: Jan 2001 Location: McKinney, TX Posts: 1,294	Re: Gears question in my 03 Mach 1 The difference in gas should only be 1-2mpg if that. It's only a 15% steeper gear than stock. Plus the TR3650 has a pretty tall 5th... __________________ Strike down the unroadworthy! 2000 GT Atl. Blue: '03 Cobra motor - 465rwhp/473rwtq, T-56 6-speed, full MM TA/PH & tubular K-member suspension, Saleen body, 17" Torq-Thrust II's, M/T ET Street radials, and lots more '94 Rio Red Cobra: All the bolt-ons, 3.73s

01-30-2005, 06:49 PM	#11
Mustang Brandon Registered Member Join Date: Feb 2004 Location: louisville, kentucky Posts: 88	Re: Gears question in my 03 Mach 1 use the analyzer at this site i think its pretty close __________________ black 89 lx hatchback 5.0, 17x9 polished Cobra R's wrapped in 215/50/17 up front and 245/40/17 out back , perfectly clean and original interior less than 1,000 miles on new t-5, throw out bearing and clutch. completly redone exaust shorty headers, custom h pipe, flowmaster 40 series, all mandrell bent 2.5 inch tubing i got all new headlight assembly for christmas with clear corners www.50resto.com

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
simple question	Lonzo	Classic Mustangs	3	09-10-2002 09:37 AM
power question	66StangGuy	Classic Mustangs	1	02-27-2002 06:55 PM
Question about Mach 460	tireburner163	Blue Oval Lounge	2	02-26-2002 07:41 PM
Mach 460 Question	NinetyEightGT_Man	Audio, Security, & Electronics	2	07-24-2000 06:17 PM