Determining Rear End Gears

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Aug 7, 2024 | 09:48 AM

KWRB

Thread Starter

5th Wheeling

Joined: Jul 2024

Posts: 47

Likes: 5

From: Central NY

Determining Rear End Gears

Are rear end gears in the VIN code for 1989? I don't believe they are. How can I determine the ratio?

Thanks!

Aug 7, 2024 | 10:13 AM

Mudsport96

Logistics Pro

Joined: Aug 2010

Posts: 3,716

Likes: 583

From: Chillicothe

By looking at the door jamb sticker and seeing what the AXLE code is and letting us know. Or googling what is printed there

Aug 7, 2024 | 10:22 AM

KWRB

Thread Starter

5th Wheeling

Joined: Jul 2024

Posts: 47

Likes: 5

From: Central NY

Quote:

Originally Posted by Mudsport96

By looking at the door jamb sticker and seeing what the AXLE code is and letting us know. Or googling what is printed there

I am not with the truck at the moment. Is there a decode table available, that you, or someone else, could share?

Thanks again!

Aug 7, 2024 | 10:26 AM

tjc transport

i ain't rite

Joined: Mar 2005

Posts: 65,505

Likes: 5,563

From: Marlboro Mental Hospital.

on top of FTE page is a black bar. in it is "tools" click on that and look for VIN decoder in the drop down menu.

Aug 7, 2024 | 10:44 AM

rla2005

Fleet Owner

Joined: Oct 2005

Posts: 20,786

Likes: 1,751

From: Kentucky

1989 Axle Code table:

Attached Images

Aug 7, 2024 | 10:54 AM

KWRB

Thread Starter

5th Wheeling

Joined: Jul 2024

Posts: 47

Likes: 5

From: Central NY

Quote:

Originally Posted by rla2005

1989 Axle Code table:

Awesome! Thank you!

Aug 7, 2024 | 12:35 PM

1Butcher

Cargo Master

Joined: Mar 2007

Posts: 2,822

Likes: 1,029

Don't forget, the truck is old and unless you have owned it from day one, you really do not know what the gearing is.

My truck came with a 3.55 and now has 4.10. Nobody knows but me and those that can read.

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Aug 7, 2024 | 01:49 PM

Mikulh

Laughing Gas

Joined: Dec 2005

Posts: 904

Likes: 115

From: Laurel, MS

Quote:

Originally Posted by 1Butcher

I agree... My door tag indicates a 2.73:1 ratio, but I changed them out to 3.27:1 years ago (I got them as a low-mileage take-off from a mustang). I wish I'd gone to 3.73:1...maybe some day.

The easiest way to be sure is to put the rear end on jack stands, transmission in neutral (with the front wheels chocked), turn the driveshaft by hand and count how many times you have the turn the driveshaft before the tire turns one full turn. For Example: If you have to turn the driveshaft 3.5 times for the wheel to make one revolution, then that's a 3.55:1 ratio.