[carolynmead8463]

I'm looking to replace the third member in my 9". I want to go with 2.73 gears. What models came with the 9" and 2.73 gears? When I call around to different yards they have no idea what they have unless I can give them a year and model.

 

[PSIG]

The problem is that they will not know what gears are in it. From the '60s through the '80s, most mid-size cars were optioned with the 9", and most full-size cars and pickups had them, but each year and model had their own door data plate codes. Most reliable is reading the axle tag, and the 2.75:1 ratio is the closest common ratio to your search. The tag will have "2.75" (open) or "2L75" (limited-slip) stamped on it. Apparently, 2.73s did exist (mostly '80s trucks), but I've been through a lot of these, and don't recall seeing one.

Use care, as 8" are similar appearance, as are the HD 9-3/8". The 9-3/8 will interchange the entire center section into a 9" axle housing with some minor filing or grinding to get it in the hole, but just the gears won't fit a 9" carrier. In that beast, the 2.80 ratio would be closest, and often came with limited-slip in trucks and BIG cars. Service parts are limited to seals and bearings with some searching, and you may need a conversion U-joint to get it in your ride, perhaps a new driveshaft (yokes were shorter in some, especially trucks).

I just put on my grimy clothes, gloves, water bottle, flashlight, eye protection, and extension mirror or endoscope and hit the wrecking yards. Phone calls and attendant opinions are generally unreliable. Be aware many 'yards have some stashed in the back room, pulling them for buddies when they come-in. Be friendly and you might luck-out, but don't bend-over for a bad price. Make your search into a fun outing!

 

[carolynmead8463]

The problem is that they will not know what gears are in it. From the '60s through the '80s, most mid-size cars were optioned with the 9", and most full-size cars and pickups had them, but each year and model had their own door data plate codes. Most reliable is reading the axle tag, and the 2.75:1 ratio is the closest common ratio to your search. The tag will have "2.75" (open) or "2L75" (limited-slip) stamped on it. Apparently, 2.73s did exist (mostly '80s trucks), but I've been through a lot of these, and don't recall seeing one.

Use care, as 8" are similar appearance, as are the HD 9-3/8". The 9-3/8 will interchange the entire center section into a 9" axle housing with some minor filing or grinding to get it in the hole, but just the gears won't fit a 9" carrier. In that beast, the 2.80 ratio would be closest, and often came with limited-slip in trucks and BIG cars. Service parts are limited to seals and bearings with some searching, and you may need a conversion U-joint to get it in your ride, perhaps a new driveshaft (yokes were shorter in some, especially trucks).

I just put on my grimy clothes, gloves, water bottle, flashlight, eye protection, and extension mirror or endoscope and hit the wrecking yards. Phone calls and attendant opinions are generally unreliable. Be aware many 'yards have some stashed in the back room, pulling them for buddies when they come-in. Be friendly and you might luck-out, but don't bend-over for a bad price. Make your search into a fun outing!

Thanks, Not my first parts search, but my first for 9" stuff. The info is good stuff.

 

[5851a]

2.75 very common around here in the big cars with automatics and pickups. 2.73 seemed to be reserved for the 9 3/8 rears in Lincolns/Thunderbirds in the 70's. Manuals seemed to come with 3:25's or 3:00.

 

[Monroepitt]

I know from experience that some of the vans did. I had a leak in a 1969 F100 that I did not know about and ended up getting so hot the pinion shaft bent when I pulled over due to smoke coming out the back. My uncle got me to a wrecking yard, and we pulled a 9" out of a 63 Ford Econoline Van. It was a 2.73 ratio until I bought a ring and pinion and changed it to a 3.25. I then put in a C6 and it worked great with the automatic. We chose the Van because it was upside down.

 

[Bsquared55]

I'm looking to replace the third member in my 9". I want to go with 2.73 gears. What models came with the 9" and 2.73 gears? When I call around to different yards they have no idea what they have unless I can give them a year and model.

I have a 1968 Galaxie 500, base model not XL, 2-door hardtop, 390 2bbl, and 9" open with 2.73:1 gears,
It's an interstate dream machine with those gears. I get 14 mpg combined.
Not sure if that helps you or not.

 

[Bsquared55]

OOPs, my rear is probably the 2.75:1. I haven't been under it in a long time

 

[carolynmead8463]

Thanks, 2.73 or 2.75, Either will work for me. I'm in Michigan so most of the big cars with 9" have rusted and gone to the crusher when the 8.8" came out. Thanks again.