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Old 10-31-2012, 12:31 AM   #1
shipma2
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found this stamped on the ring in rear end

41:11 does this mean 41 divided by 11 which is a 373 gear ratio? is 373 any good for a k10? is a twelve bolt a strong axle?
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Old 10-31-2012, 12:32 AM   #2
shipma2
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Re: found this stamped on the ring in rear end

thanks in advance
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Old 10-31-2012, 12:43 AM   #3
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Re: found this stamped on the ring in rear end

It is a 3.73 ratio. I think 3.73 is a good all around ratio. Decent mileage and still good pep. The 12 bolt is plenty strong.
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Old 10-31-2012, 05:38 AM   #4
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Re: found this stamped on the ring in rear end

thanks so the one out at the salvage yard should fit perfectly i think i may order a rebuild kit too have on hand too
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Old 10-31-2012, 06:56 AM   #5
Keith Seymore
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Re: found this stamped on the ring in rear end

Quote:
Originally Posted by shipma2 View Post
41:11 does this mean 41 divided by 11 which is a 373 gear ratio?
Yes.

If you count the teeth you will find 41 teeth on the ring gear and 11 on the pinion. 41 / 11 = 3.73

K
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Old 10-31-2012, 11:19 AM   #6
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Re: found this stamped on the ring in rear end

3.73 is a good ratio if you have 31 to 33 inch tires, but I can tell you from personal experience, it's lousy with 40 inch tires.
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Old 10-31-2012, 11:31 AM   #7
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Re: found this stamped on the ring in rear end

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Originally Posted by wilkin250r View Post
3.73 is a good ratio if you have 31 to 33 inch tires, but I can tell you from personal experience, it's lousy with 40 inch tires.

Most trucks could use a gearing changes when running anything bigger than 35s, hell my yota had 5.29s
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Old 10-31-2012, 11:36 AM   #8
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Re: found this stamped on the ring in rear end

Yep, that would be 41 on the ring and 11 on the pinion, 3.73. The ring gear is usually stamped with this. For most stock or mildly modified trucks the 12 bolt is plenty strong, now if you are running 37" plus tires and offroading it hard, sure you will need to look for something stronger, but for normal driving, slight offroading and a little playing around it is fine. Better than the 10 bolts.

Quote:
Originally Posted by wilkin250r View Post
3.73 is a good ratio if you have 31 to 33 inch tires, but I can tell you from personal experience, it's lousy with 40 inch tires.
I can imagine, I had 5.13s with 38s and I wanted more
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Old 10-31-2012, 11:57 AM   #9
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Re: found this stamped on the ring in rear end

The weakest link in the truck 12 bolt is the pinion diameter at 1.4". I've snapped mine twice now on the street playing around. Just the grunt of the engine and loafing around a 4,960 lbs. 4x4 blazer takes a toll on it.

Passenger car 12 bolts have a 1.625" pinion so you never see this problem.

I'm looking for a semi float 14 bolt to drop in now for a little more strength so I don't have to keep driving it home in 4hi on the front axle
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Old 11-01-2012, 12:42 AM   #10
shipma2
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Re: found this stamped on the ring in rear end

ha ya im running mine in 4 hi on the front till i can afford another rear end too actually
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Old 11-01-2012, 10:59 AM   #11
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Re: found this stamped on the ring in rear end

I only did that when it broke. Now I just try to be a little easier at the stoplights until I find something better. Although I'm taking it to the dragstrip for club track day this weekend to get a time out of it. Gotta drive it about 300 miles so I better take it easy out of the hole and keep it in one piece
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Old 11-01-2012, 05:17 PM   #12
shipma2
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Re: found this stamped on the ring in rear end

ya gotta love them old chevs
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