Rear End Gears

[RDF]

I'm thinking of getting some new gears for my car (73 'Cuda).  Right now it's got a 360 in it (auto trans) and the gears are about high 2's.  I was thinking of putting in 373's, but don't know what I would need, where to look, etc.  I've got a good shop down here (a friend of a friend) who will put them in for $200.00, so I was thinking of doing it....  can anyone point me in the right direction?

 

BTW, I've got a 440 that I'm building so that will go in about a year or so down the road.

[Chryco Psycho]

there are a lot of companies that have gear sets , Strange , Eaton , Richmond , Motive , Yukon , Zoom , Check with Summit or Jegs or local speed shop for price on gears & brgs kits

[matt63]

I just got a set of 3.55's from these guys http://www.yukongear.com/
I really like this ratio.  I think anything higher numerically will be a tough go on the highway.  I think you will need a bearing kit too.

[GoodysGotaCuda]

I'd think you would look into some 3.55s or so. You have some short tires and a big block for torque. Should be great to cruise in. Just my 2cents!  Summit or someone should have a kit to set everything up with shims, seals and all that.

You got a sure-grip? You'll want one unless you want that big block doin one tire fires!

[MEK-Dangerfield]

If you have the typical 26" tires, I wouldn't plan on too much hiway travel with 3:73's. It's all in how you plan to drive the car.


  Mike

[Carlwalski]

Doesn't "really" matter where you get them from, most if not all are cut at the same place and boxed in there different labels, or something like that anyhow. So says Dr-Diff and he should know. I got my rear gears from Randys Ring & Pinion the brand was Yukon but who really cut them, who knows.....

[AMXguy]

 Can you use any ratio in any 8 3/4 ? one time I heard there was a high ratio carrier and a low ratio one?

[tactransman]

Yes, you can use any ratio in an 8 3/4. The fact that they use "spanner nuts" instead of shims for the side bearings makes that possible.

[Rare_T_A]

3:55's are a great gear for cruising. That is what I have in the RR. With 275X60X15 tires make them work great. I'm guessing that with these tires I'm close the the 3:23's with the small 14in tires that were on the car origionally. The T/A has 4:88's and they are great in town but not much for highway cruising. 

[kudakidd]

Got 3.54's (Dana) in the kuda. perfect ratio for hwy and acceleration

[73Chally]

I put 3.91s in mine, with slightly taller rear tires.  It's not bad for short highway runs, but if you're looking for more driveability then 3.55 would be the way to go.  I got mine through Summit for something like $190 last year.  I believe they are Richmond.  Many burnouts later they are still working fine.

[moper]

I'm not sure, but the 3.73:1 ratio is not universally available. IIRC its only for the 741 case. There are 489, and 742 casings too. The gears will not interchange in the cases, (pinion gear designs are different) but the differentials will intercahnge and take any ratio. Also budget for a new yoke just in case. Some of the lessor expensive brand may need a different yoke. Cass (Dr Diff) is a great parts source by the way.