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Gear swap questions.

I am getting ready to order some 3.73 Richmond Gears for my 88 Thunderbird Sport.

I just wanted to make sure when going from the factory AOD 2.73 to the 3.73 gears that the proper Driver Gear to get my speedo correct would be a 23 tooth gear.

Also when it comes to installing the ring and pinion gears, is this something that a handyman can do, or is it best left to a professional with the right tools? I dont want to hear the gears, or atlest not that much.

Thanks.

Gear swap questions.

Reply #1
If you don't know how to set the lash, then I'd probably recommend a pro doing it, I don't think I'd tackle rear gears by myself...;)

Here's a chart that someone linked me to awhile back when I was figuring out what I needed:

http://www.fordracingparts.com/download/charts/129.pdf
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Gear swap questions.

Reply #2
You will definably need a dial indicator. It's not real hard, you do need to understand a wear pattern so you can adjust the shims the right way. Here's one place to study.
http://www.angelfire.com/theforce/5ohcpa/cpa5ohtech001.htm
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Gear swap questions.

Reply #3
A local shop put the 3.73's into my 7.5 rear for about 300 bucks. They have all the right tools to do it and it was done in a day. Was driving it the next day.

My buddy wants to put the LSD and 3.73 gears into my Toyota 6.7 rear this summer, so I figured I should learn!

He does have all the tools.

Chris
"I put my foot in my tank and I began to roll." Chuck Berry

Gear swap questions.

Reply #4
Buy the FORD gears  they are much quiter  and easier to set correctly

  Just my 2 cents




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Gear swap questions.

Reply #5
I am a do-it-myself kind of person.  I bought my dial gauge and magnetic base from Harbor Freight.  Aside from some large sockets and 3/2-jaw puller it wasn't all that difficult.  Read through the guide here:
http://www.corral.net/tech/drivetrain/gears.html

I highly advise making a set of set-up bearings:
http://www.explorerforum.com/forums/showthread.php?t=144780

My gears were used ford units.  They are still quiet and running good.  I just pulled a set of 3.73s from a 02 ford explorer sport track in the junkyard to go in my cougar.

Also use an air ratchet (not impact) to spin the pinion when checking the contact pattern.  Apply a little resistance to the ring gear with your thumb to really make the pattern show up. 

I had the axle out from under the car which made life alot easier.
My car is a gravity hybrid.  The gasoline engine gets me up the hills, and gravity gets me down.

Gear swap questions.

Reply #6
The price from a local recommended garage was good, so i will let the professional do it.

My other question would be for an automatic, what gear would everybody go with?

This car is a fun car only, city and country cruises. Will 3:73s satisfy the accelerator in me?? or should i go 4:10s or more??

Gear swap questions.

Reply #7
3.73 would be a better choice, unless you're planning on doing a lot of racing.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Gear swap questions.

Reply #8
I am almost certain on the 3:73s.

Looking online at Summit Racing, the Richmond 4:10 gears say they require a different cross pin, and that they wont work with the Auburn Carrier.

Is the carrier the traction lock module?? so without switching out the traction lock module i am limited to 3:73??

Do i have this right?

Gear swap questions.

Reply #9
You can put 4.10s on a stock carrier (which is the traction lock module).  Is this a DD?  I don't think I would put 410s on a DD.  I have 355s in my SC and they provide pretty good scoot.  I plan on putting 373s in my T5 weekend warrior.
My car is a gravity hybrid.  The gasoline engine gets me up the hills, and gravity gets me down.

Gear swap questions.

Reply #10
Its a dedicated fun car for the street and country cruises.

Automatic.

So then our 7.5 Ford rear ends do not have Auburn carriers.