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Richard
10-02-2006, 04:09 PM
I have in my Hawk a 45B TT Rear Axle. I would like to know the gear ratio. Thanks Richard

1956 Hawk
10-02-2006, 04:50 PM
I take it the 45B is the production order number? If you are trying to figure out what ratio is in the car right now, the easest way is to look at the tag on the back of the differential. It should be under one of the bolts on the rear cover and either list the ratio or the number of teeth on the ring and pinion. If the tag isn't there anymore you can either jack up the rear of the car and turn the tire and count the number of revolutions of the tire and drive shaft, or you can take the rear cover off the diferential and the ratio is stamped on the ring gear.
Hope this answers your question.
David

Richard
10-02-2006, 07:10 PM
The 45B is the tag on the differential. I figured it would tell what the gear ration is.

1956 Hawk
10-02-2006, 07:14 PM
You sure that it isn't 4.56? What engine and transmission are in your Hawk?
David

Richard
10-02-2006, 07:18 PM
Maybe it is a 6 and not a B. Does that mean it is a 4.56 ratio? Hate to say this, but it has a GM in it.

Richard
10-02-2006, 07:24 PM
We used to run 4.11 in drag cars, but never heard of a 4.56

1956 Hawk
10-02-2006, 07:25 PM
I ment what was the original engine and transmission? The 4.56 was an optional gear ratio, but I would be supprised if it came in something other than a 6 with overdrive. By the way what year is the Hawk?
David

bob40
10-02-2006, 07:30 PM
4.56 was a pretty common street gear for the serious guys up here.You could get 4.56 gears in a 6 cyl. 3-spd/od Ch***y in the mid 50's

1956 Hawk
10-02-2006, 07:38 PM
4.56 was the lowest gear offered by Studebaker for the Dana 44 differential. I think all the options were 3.07, 3.31, 3.54, 3.73, 3.92, 4.09, and 4.56.
David

Richard
10-02-2006, 07:38 PM
1960 Hawk. The GM was already in the car when I purchased it. So don't know what was in it originaly. I know it is very low gear. With GM engine it will leave 26 feet of rubber easily.[Both sides leave equal amount] But only get about 12 mpg on the road. I took a 600 mile trip and it was expensive on gasoline.

Richard
10-02-2006, 07:41 PM
Gotta eat supper. Will check back in a few

1956 Hawk
10-02-2006, 07:49 PM
With 4.56s you must be turning about 3500rpm at 55mph. By the way if you want to change the gears you can swap in some 3.73s without to much trouble. Anything higher than that and you would have to change the carrier.
David

Transtar60
10-02-2006, 08:18 PM
45B is a type of Twin traction axle, it is a code that refers to the
angle of the ramps in the TT mechanism , the shop manual refers to this.

The axle ration should be a seperate tag with either one number like
4.11 or 4.56 or two numbers, one over the other.



5E13
7E7
8E7
8E12
8E28
4E2
59 Lark
etc

Richard
10-02-2006, 08:41 PM
I double checked and it is a 45B tag under the bolt head. I haven't seen another tag but could be somewhere other than on rear side of casing which can easily be seen from rear of car. Will do some more looking tomorrow. Richard

Chicken Hawk
10-02-2006, 09:09 PM
I don't think Stude had a 4.56 in the V8 with the 44 housings. The 4.56 is the Chevie gears and Stude used a 4.545 which Stude called 4.55. Also, I think the 4.55 can be substituded with a 4.27, 4.09 or 3.92 but any numbers lower than 3.92 would require a different carrier.

Ted


quote:Originally posted by Richard

I double checked and it is a 45B tag under the bolt head. I haven't seen another tag but could be somewhere other than on rear side of casing which can easily be seen from rear of car. Will do some more looking tomorrow. Richard

Richard
10-02-2006, 09:50 PM
I am going to have to replace it with a higher gear, so was just trying to figure out what I had to start out with. The tag that said 45B was all I could find at first, but will double check tomorrow and see if I can find another tag somewhere. I have enough power for even a 256 or around there. Richard

N8N
10-02-2006, 09:53 PM
45B just means it's a Twin Traction. There should be another tag on there, either with the ratio or something like 41/11 which would be the tooth ratio of ring to pinion (in my example, a 3.73:1 ratio) if the other tag is missing you will have to either count the teeth or else have a helper count revs for you.

good luck,

nate

--
55 Commander Starlight
http://home.comcast.net/~njnagel

Transtar60
10-03-2006, 12:09 PM
quote:Originally posted by N8N

45B just means it's a Twin Traction. There should be another tag on there, either with the ratio or something like 41/11 which would be the tooth ratio of ring to pinion (in my example, a 3.73:1 ratio) if the other tag is missing you will have to either count the teeth or else have a helper count revs for you.

good luck,

nate

--
55 Commander Starlight
http://home.comcast.net/~njnagel


Hey N8 see my post above.
Like someone else said, he could also pull the cover and look for the numbers stamped into the side of the ring gear.

5E13
7E7
8E7
8E12
8E28
4E2
59 Lark
etc

farmhawk
10-03-2006, 10:28 PM
I have the 45B tag on my Dana 44, which is in my 61 Hawk and the gear ratio is 3.54.

Wayen
61 Hawk (Project)

Richard
10-03-2006, 11:22 PM
I wiped the surface clean and found the other tag. It was so flat you couldn't hardly see it, But it said 41/11 3.07 So now I know it is a 3.07??? But if you divide 11 into 41 it comes out 3.72. So I'm not sure????? Thanks alot to all of you guys. Richard.

Transtar60
10-03-2006, 11:34 PM
http://www.ringpinion.com/content/calculators/RPM.asp
Onthis page you will find several calculators.

The ring gear has 41 teeth
the pinion gear has 11 teeth
41 divided by 11 = 3.727272, , rounded off to
3.73

5E13
7E7
8E7
8E12
8E28
4E2
59 Lark
etc

Richard
10-03-2006, 11:48 PM
Why did the tag say 41/11 and under it said 3.07 ???

Richard
10-03-2006, 11:52 PM
I'll double check tomorrow. Maybe it said 3.70 instead of 3.07 Now I'm getting bumfuzzeled. Turned 68 Sunday and my minds probably slipping.

Richard
10-04-2006, 02:41 PM
I took my time and wiped everything real clean and the tag says it is 43/14 and below that says 3.07 So divide 14 into 43 and it comes out 3.07. So now I know for sure what it is. Thanks to you guys I have finally figured out what gear ratio I have in my Hawk. Again Thanks guys. Richard

1956 Hawk
10-04-2006, 03:16 PM
If your differential actually has 3.07 gears in it you should be getting better gas milage. Do you have a tachometer and if so what rpm are you running at 60mph. I would guess that you just need to spend some time tuning your engine.
David

StudeRich
10-04-2006, 04:00 PM
Sure, you never said what's under the hood except GM, it could be a SB 400 with a 750 CFM carb.! Or the axle ratio tag may lie[:0] anything is possible! Either of which would account for the poor mileage, even an incorrect speedo, with an engine swap, that's a good possibility.


quote:Originally posted by 1956 Hawk

If your differential actually has 3.07 gears in it you should be getting better gas milage. Do you have a tachometer and if so what rpm are you running at 60mph. I would guess that you just need to spend some time tuning your engine.
David

StudeRich
Studebakers Northwest
Ferndale, WA

Richard
10-04-2006, 06:03 PM
Got to get me a tach, but I didn't know this, but after driving 400 miles to pick the car up, I asked what is with this motor, and the seller said, It's bored 40, a 5/8 cam, and 600 holley, but the car was in such good shape I took it anyway. Fast little car, but it was 100 degrees outside on the trip I took, and ran A/C all the way, so I guess I shouldn't grip.