Gears & Axles - Tallest gear for beefy rear end?! (like <= 2.73)




gi8e7oi825
02-23-2012, 10:46 AM
Long story short, the rear end in my Firebird is whining and needs to be replaced. What's the tallest gear I can get in an aftermarket rear end? And, other than "junk yard" and "ebay" where can I buy one? I'm having a difficult time finding shit on the vendors' sites.

I hate going to the track. For me it's absolutely pointless. I do mostly highway driving like an old geezer and want to maintain my 24-25 mpg at 70 mph ... so I don't consider 3.42s or even 3.08s acceptable. I currently have 2.73s in my A4, but if anything taller exists, I'll take that instead! If all else fails I'll get another 10 bolt...

Thanks in advance for your help!


ROCNDAV
02-23-2012, 11:41 AM
You're only getting 24/25 with 2.73s?

I was getting that when I had the stock 323's.

So are you asking where you can buy a Moser 12 bolt or Ford 9 inch with 2.73 or numerically lower gears?

Any sponser should be able help. Most people are usually looking for 3.42, 3.73's and 4.11's so that's probably what you will see listed on most websites. It shouldn't be a problem to get 2.73's, it just isn't as common to request that gearset IMO.

gi8e7oi825
02-23-2012, 11:51 AM
I've called Moser & Strange and they told me to go elsewhere lol. Yes my gas mileage sucks. Maybe 'cause of my 17x10.5s and 315s? Hell if I know, honestly. I suppose I could starting calling up all the sponsors next...


justin hover
02-23-2012, 12:03 PM
God... get rid of those awfull 2.73s...They have no place in any ls1. I would've given you my 2.73s for free with a smile last year.

ROCNDAV
02-23-2012, 12:09 PM
Yeah, I'd call the sponsors. They will put what ever gear set you need.

Carl at CRP
02-23-2012, 12:22 PM
Please give Me a call, I will be glad to answer Your questions and give you a respectable deal on a rearend for Your car.

Carl

Cool28
02-27-2012, 04:09 PM
I have 3.00 in my 9 inch. By efilive with a .75 4th it'll be at 1200 or so rpms at 41mph locked converter and a 25.91 dia tire. So 4l60 are I think .69 4th. So you could run a 3.00 and run alittle taller tire. That's what I'm doing

jimmyblue
02-27-2012, 06:10 PM
Older 10-bolts had a 2.56 option, but I have no idea
whether this is a factory ratio for any 7.5" 10-bolt.
But it's the next sensible even ring/pinion ratio down,
and I've never seen anything lower as a factory option.

Awake455
02-27-2012, 06:31 PM
There were some stupidly tall gears in the 10 bolts in the early 80s, like in the G body cars.

Tallest gear I ever laid my hands on (for a 9") was a 2.50.

b_evans06
02-27-2012, 06:37 PM
Yea my 84 g body cutlass had factory 2.41 gear ratios in the 10 bolt. It was a 6cyl auto car.

69TA
03-05-2012, 09:30 PM
get 2.41's that is the lowest I have seen from a GM rear