Jump to content
TEAM SHELBY FORUM

3.73 Gears


Recommended Posts

Alright, I need some help from the pros. As I was buying my FR 3.73 gears, Shelby recommended installing a Special Carrier Cross Shaft to allow for clearance on 3.73 or higher... I've checked online and asked shops and no one but SPP is offering (or recommending) this part.

 

Can anyone shed some light as to if this is really needed?

http://www.shelbyperformanceparts.com/Show...ss%20Shaft.aspx

 

SPP also is sold out and will not have it for 2+ months.

Link to comment
Share on other sites

Alright, I need some help from the pros. As I was buying my FR 3.73 gears, Shelby recommended installing a Special Carrier Cross Shaft to allow for clearance on 3.73 or higher... I've checked online and asked shops and no one but SPP is offering (or recommending) this part.

 

Can anyone shed some light as to if this is really needed?

http://www.shelbyperformanceparts.com/Show...ss%20Shaft.aspx

 

SPP also is sold out and will not have it for 2+ months.

Hey, I have 373 in my car from ford racing and had my dealer do the install nothing mentioned nothing wrong so just get the gears and don't listen to a salesman. My gears are a yr old 2x to south carolina and many many hard starts and shifts. But dont try it on the street thats illegal and wrong. :drool: Gotta go meds time nite nite :drool:

Link to comment
Share on other sites

You do not need the carrier cross shaft piece. The shop just finished installing 3.73s in mine. I ordered the gears from Ford Racing (4209-F373N). They come with shims and crush collar and nothing else was needed except the pinion bearing. The shop couldn't salvage the one off the 3.55s.

 

Your PCM will have to be flashed for the new gears.

Link to comment
Share on other sites

Some pretty good advice has been posted here, and that's nice to see. I agree with everything posted so far, and I have more that a few gear swaps under my belt. The cross shaft spoken of is a real thing, but applies to 4:56 and up, it's not required for numerically lower geat sets.

 

IMHO, there is not enough "bank for the buck" with a step up to 3:73s. Same labor costs, same parts cost, but not enough "oomph" as the 4:10s will deliver. Moreover, FRP has an install kit that provides ALL the bearings and shims you should replace in a gear swap. Don't recycle old parts to the new, in this case it will cause you problems down the road. FRP P/N is M-4210-C, $120.00, and don't forget the friction modifier!

Link to comment
Share on other sites

I am a pro and I told you! :)

 

Seriously though I think I'd have to agree that the 3:73's probably aren't going to add much. I know you're concerned about the top end speed, but let me just say this..... 120+mph is STILL very possible and it doesn't whine that bad. At 80 you're pretty much at 3000rpm's, but seriously... We live in So Cal, when do we ever get the chance to drive 80!??!! :)

Link to comment
Share on other sites

I agree with LuLu,the 373's will do little and cost you the same price. I've spoken with a gear shop close to me and they recommend the 410's for a noticeable difference. They only install original factory gears and so i'm wondering what's the difference between factory and Ford Racing gears. They also do not recommend 390's on account they are only made by Motive and they sometimes whine.The 390's do seem like the best comprise but i don't want any noise. GOOD-LUCK on your choice.

Link to comment
Share on other sites

You do not need the carrier cross shaft piece. The shop just finished installing 3.73s in mine. I ordered the gears from Ford Racing (4209-F373N). They come with shims and crush collar and nothing else was needed except the pinion bearing. The shop couldn't salvage the one off the 3.55s.

 

Your PCM will have to be flashed for the new gears.

 

 

Will the flash affect the shelby gt tune the car came with?

Link to comment
Share on other sites

If you want to retain the original tune with the new gears you will need to contact Ford Racing. In short, call them, give them the last six digits of your VIN and tell them what you are doing. They will fax you an application form to fill out and return (you can fax it back to them). Shortly after, like a week, they will contact you for payment. The cost is $250 up front for the new tune and tuner. $100 will be refunded to you upon return of the tuning device. The device will save your original Shelby/Ford Racing tune with the 3.55 gears and install the new Shelby/Ford Racing tune with 3.73 gears. I opted to keep the device. I dealt with Raymond (technical) and Mitchell (warranty and payment) at Ford Racing. Both were really great. (1-800-367-3788)

Link to comment
Share on other sites

Great info guys. Thanks for all your input. I know the 4.10 is a better bang for the buck, but most of my daily driving is on an open freeway. Not that I'm planning to do 150 (again) :drool: I just didn't want the high RPM as I'm cruising on 70-75. But 4.10 would make more sense.

 

 

I am a pro and I told you! :)

 

HORSBYT, I know you were right, but you're my boss so it's just natural that I don't listen. :happy feet: wait, it's not review time yet, is it? :doh:

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...
...