Gears install

txredgt

10 Year Member
Oct 26, 2009
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So I think the next step for me with my ride is a set of 3.73 gears from the stockers.. I do alot of highway driving so 4.10's are out of the question. I was wondering what people on here thought about doing the install myself and if anybody else has done it themselves. Usually I'm not one to do my own work on a 'vital' part of my car but I was thinking I could save some extra bucks on it. Also anybody who had it professionally installed how much did they charge you to do it? I will be around Dallas so I thought about swinging by DM and having them do it but I don't want to overpay for an easier job. Also I was told the car has a chip on it but I am not sure what brand or anything so would I need a new tune due to the change of gears? Any help with these questions would be great. :)
 
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A gear install is one of the toughest jobs to do on a mustang. You have to really know what you're doing. If you're not absolutely precise, you risk having noisy gears after the install. I'd definitely suggest having a professional install them.

As for paying someone, look for around $200-$300.
 
Besides being noisy, they could wear prematurely if they aren't installed/shimmed correctly. Definitely a job for professionals. Call around different shops in your area, besides DM to price it.

As far as a chip, only thing you can do is look around the PCM or under the dash. I'm not really sure, I've never dealt with a chip. I do know, however, that when you get gears installed (3.73 for manual; 4.10 for auto trans) that you will need some way to correct the speedometer.
 
I would not do a ring and pinion swap unless you know what you are doing.

Use Ford Gears. 4.10's are not too much gear, even if you drive a ton of miles on the highway. Plenty of cars with 100-200k and 4.10's. Make sure you have rubber if you want to hook in 1st and through 2nd. Gears are worthless, and can hurt your performance if you don't have the proper traction, even though they make the car a lot more fun to drive.

A good performance shop can knock this out in 2-3 hours if they work hard. $90-110 is the going rate per hour.
 
I agree with these guys that its pretty much the hardest thing to do to a car, but anyone who knows how to swap gears had to do it a first time and not know exactly whay they were doing, I say go for it just dont plan on it being a 1 day job.
 
I agree with these guys that its pretty much the hardest thing to do to a car, but anyone who knows how to swap gears had to do it a first time and not know exactly whay they were doing, I say go for it just dont plan on it being a 1 day job.

Buying the same parts over because you broke them is not fun. Buying other parts that you broke in the process just adds insult to injury.

Peace of mind is worth ~$200.
 
I ****ed up my first set, cost me like 100-150, but now that Ive done like 10 gear swaps its actually saved me like 2Gs in instalation fee's. Mine first set only got messed up cause I forgot to put lictite on 1 of the bolts and it came out and got chewed up by the gears. IDK, I say go for it
 
I ****ed up my first set, cost me like 100-150, but now that Ive done like 10 gear swaps its actually saved me like 2Gs in instalation fee's. Mine first set only got messed up cause I forgot to put lictite on 1 of the bolts and it came out and got chewed up by the gears. IDK, I say go for it

I would to, but for some it's not a good idea. Another thing to worry about it getting a press, besides setting lash perfectly.
 
IF ur gonna be in Dallas, drive to south arlington and have Gearheads performance do it. I had mine done last week, if you dont need bearings, install/all parts and frpp gears is only $350. if it needs bearings, then its an extra $100. Pretty sweet deal imo.
 
Thanks for all the input and the how to do it yourself link. Spederman that sounds like too good of a deal to pass up right there.. the cheapest you can get frpp gears from what I have seen is $150 and up to $200 so when I get to it that will probably be where I take it to.

IF ur gonna be in Dallas, drive to south arlington and have Gearheads performance do it. I had mine done last week, if you dont need bearings, install/all parts and frpp gears is only $350. if it needs bearings, then its an extra $100. Pretty sweet deal imo.
 
I know this has been talked about before.. and i searched for it but only found a few threads about 4.10's.. all the 4.10 vs 3.73 links were dead... You said you do a lot of highway and therefore chose 3.73's... What is the RPM difference at say. .70mph. Where there any other reasons you chose 3.73's over 4.10's?
 
I actually do not know the difference numberswise between 3.73 and 4.10's but it seems the right choice for me. I live about 40 miles 1 way outside of San Antonio and currently I drive there at least twice a week but in the past and near future I hope to be driving there more often for school/job. 400 miles a week plus whatever other driving and thats alot of miles with a high gear ratio.

I know this has been talked about before.. and i searched for it but only found a few threads about 4.10's.. all the 4.10 vs 3.73 links were dead... You said you do a lot of highway and therefore chose 3.73's... What is the RPM difference at say. .70mph. Where there any other reasons you chose 3.73's over 4.10's?
 
The difference between 3.73's and 4.10's at cruising speed is around 200 RPM.

When you have the gears done, if you have some miles on the car it's a VERY good job to not only replace all of the rear end bearings (including axle bearings and seals), but to have the limited slip rebuilt as well. Ford sells their trac-lok rebuild on Summit Racing for around $40, and you will need friction modifier as well.
 
So do you happen to know the difference between the stock and the 3.73 ratio? Also for some of you who have similar mods as I do you might be able to tell me what type of milage to except after it: cold air, upper intake, bbk long tubes, h pipe (no cats), pypes exhaust and some kind of performance chip but I don't know what brand. Its also a 5 spd car.
 
Stock gears are 3.27. I went with 3.73s and as of last year I now have 4.10s. At 70mph I'm at 2600 RPM (I have an automatic). My mpg has not changed much. I filled up yesterday and averaged 17mpg half highway and half city driving. That's with 4.10s and stage II cams. All highway I would be around 23 mpg. I say that's not bad for a 350HP car. You would probably get 25+ mpg on the highway with a manual, stock cams and 4.10s.
 
Stock gears are 3.27. I went with 3.73s and as of last year I now have 4.10s. At 70mph I'm at 2600 RPM (I have an automatic). My mpg has not changed much. I filled up yesterday and averaged 17mpg half highway and half city driving. That's with 4.10s and stage II cams. All highway I would be around 23 mpg. I say that's not bad for a 350HP car. You would probably get 25+ mpg on the highway with a manual, stock cams and 4.10s.

great info... would like more info like this. I've pretty much decided on 4.10's 200 rpm's at cruising speed isn't bad at all.
 
I actually do not know the difference numberswise between 3.73 and 4.10's but it seems the right choice for me. I live about 40 miles 1 way outside of San Antonio and currently I drive there at least twice a week but in the past and near future I hope to be driving there more often for school/job. 400 miles a week plus whatever other driving and thats alot of miles with a high gear ratio.

Take your car to Corey at Henderson Performance in New Braunfels.
 
For reference, my car is a 2000 5 speed with the T45 transmission. At 60mph, I am around 21-2200 RPM.

70mph I run about 2600, and 80mph is almost dead on 3k. If you have a mid-01+ GT, you'll have a different transmission (if it's a 5 speed), and it'll have a SLIGHTLY better 5th gear in terms of cruising RPM.

If you are torn, there's always 3.90's...