My 9 Incher Needs HELP! [Archive]

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19Fordy

12-19-2003, 09:52 PM

OK, Where can I get a 3:73 ring and pinion for my Ford 9 inch rear. I can find 3:70 but who sells 3:73? Thanx.

Thirdyfivepickup

12-19-2003, 09:58 PM

Um... the difference between a 373 and a 370 are so slight that you wouldn't be able to tell them apart. Ever. I mean, without sophisticated computers obviously.

old beet

12-19-2003, 10:01 PM

Maybe its a 4X4.........OLDBEET

Deuce Roadster

12-19-2003, 10:03 PM

http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

They are the same basic gear.........

3.70 is a 37 ring and a 10 pinion

3.73 is a 41 ring and a 11 pinion

You could NOT see the difference on a Tach at 70 MPH or feel the difference.

I know of no 3.73 for a Ford 9 inch http://www.jalopyjournal.com/ubbthreads/images/graemlins/smirk.gif

http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

fab32

12-19-2003, 10:10 PM

DR, I think he wants to give up milage for better acceleration.

Mike Paul

12-19-2003, 10:10 PM

3.73 is a GM gear ratio I believe

choprods

12-19-2003, 11:27 PM

I think he's right- 373 not available in a 9"

Thirdyfivepickup

12-20-2003, 12:11 AM

[ QUOTE ]
I think he's right- 373 not available in a 9"

[/ QUOTE ]

So did I... until I ran across Randy's Ring and Pinion. Never dealt with them, but their catalog shows a 3.70 and a 3.73 ratio for the 9"

Go here:
Randysringandpinion (http://www.ringpinion.com/products/product.asp)

enjenjo

12-20-2003, 12:33 AM

Even in a 4x4 3.70 is close enough to 3.73 to work fine.Ford used 4.10 rear, 4.11 front, 3.70 rear, 3.73 front, 3.50 rear, 3.55 front, 3.25 rear, 3.23 front. There will not be a noticeable difference.

Randy's does have the 3.73 gears, along with many other ratios no one else lists, they are for fine tuning the gear in circle track racing.

tomslik

12-20-2003, 10:10 AM

know why they did that?

to take up driveline slack between the frt and rear diffs when in 4X4.

at least thats what they tell me...

12-20-2003, 11:07 AM

My 77 Ford 3/4 ton 4x4 had 4.10 front and 4.11 rear.
The higher gears in front were due to the front wheels traveling at a faster speed on moderately sharp corners and they pulled better on loose surfaces.
Same ratio both ends has the front end plowing on some corners.

19Fordy

12-20-2003, 11:32 AM

THANX guys. Randy's Ring and Pinion In TN. looks good. Will help keep my rear in gear.

porknbeaner

12-20-2003, 11:43 AM

You might try richmond gear. Don't have a number on 'em but if you call Summit Racing they can hook you up.

One of the reasons for slightly higher gear in the front of a 4 wheeler is to keep it going in a straight line in the sloppy stuff. The fronts pull the rears.