4-5/9 ratio Vs 3-7/12 rear end

SuperDave

I just got the 3-7/12 installed in place of the original 4-5/9. The car is a heavy four door 49 super Six. 262 Over Drive with twin H (off a Hornet) and a Pertronics 12 volt ignition. The difference is fantastic! I really don't notice any lack of acceleration power unless I am above 50 MPH. Then it doesn't quite have the throttle response that it used to have. Overdrive shifts in just right, No more early OD engagement.. Boy this car is like a new one! I highly recommend it.. Will see how she does going through the Great Smokey Mountain National park on the way to Pigeon forge this year! I found a speed cop on US-1. Had him check me at 30 and 40 MPH. The speedometer is exactly 6 MPH slower than actual speed. If I had the 4-1/10 speedo gear, that should correct it to 3 MPH error. Don't have one.. hint hint..

If you are running the stock gear in a stepdown OD car.. Consider the 3:58 out of a HydraMatic car. It is a very good combination.

DaveW.

Unknown

SuperDave wrote:

I just got the 3-7/12 installed in place of the original 4-5/9. The car is a heavy four door 49 super Six. 262 Over Drive with twin H (off a Hornet) and a Pertronics 12 volt ignition. The difference is fantastic! I really don't notice any lack of acceleration power unless I am above 50 MPH. Then it doesn't quite have the throttle response that it used to have. Overdrive shifts in just right, No more early OD engagement.. Boy this car is like a new one! I highly recommend it.. Will see how she does going through the Great Smokey Mountain National park on the way to Pigeon forge this year! I found a speed cop on US-1. Had him check me at 30 and 40 MPH. The speedometer is exactly 6 MPH slower than actual speed. If I had the 4-1/10 speedo gear, that should correct it to 3 MPH error. Don't have one.. hint hint..

If you are running the stock gear in a stepdown OD car.. Consider the 3:58 out of a HydraMatic car. It is a very good combination.

DaveW.

not to be a jerk, but the 3:58's don't grow on trees....



i can only imagine the gas mileage and speed obtainable with OD!



I love the fact that it sounds like this works well, and sounds to be a reasonable tradeoff. I had a 4:55 and went to the 4:10, which made some improvement, I would love to find that magical 3:58, but seems everyone and their brother out there has a stranglehold on them. I have even considered jacking hudsondad's 52 hornet up, swapping out the differential, and leaving him with 4:10's hehe... :cool: not like he would notice for some time.... :eek:



What I was curious of is whether anyone ever did a 4:10 to straight 3:07 swap? results?

SuperDave

Once upon a time..I had a 49 Commodore eight Conv. With Overdrive..with a 3.07. Throttle response was not in my vocabulary, but top speed and gas mileage were!

I got lucky and got this 3.58 gear from Dave Nelson in North central Fl. Came out of a 52 hydraMatic car that I think he was installing a later 3.07 into.

Park_W

I found the 3.58 with OD just a bit "tall" for my '51 Hornet. Wouldn't quite pull the hills well in OD. For a couple of other reasons I kind of wanted to go to the Spicer/Dana axle, and I had one, so put 3.73 gears in it (readily available from Reider Racing et al). Found this small ratio change made just the right difference. It pulls most hills readily now in OD which it wouldn't before. True, the gears cost a bit, and I had to pay someone with the right tools to put them in, but it was worth it.

Unknown

We parted out several '51 hydramatic cars and the center section was missing in every one. The engines and transmissions were intact, which were saved. I'm assuming all the automatic '54s are 3.07.

Geoff

Again, not wanting ot put a dampener on things, but just be aware that this is going to put a much greater load on the clutch. If the pedal starts dropping to the floor on a long pull, it would pay to go back to top gear instead of lugging in o/d. Otherwise sounds like a great set-up for long-haul driving. I have a 4.1 c & p which I am going to put in my Hornet (currently 4.55) which should be a good compromise for our hilly terrain. With the standard set up it is riduculously low-geared, and overdrive cuts in at around 20 m.p.h.

Geoff.

Park_W

Geoff, our Hornet convertible ran the 3.58 since probably 1993 or so (installed by previous owner), about 25,000 miles, with no clutch problems at all. Put the 3.73 Spicer in it two years ago. Lovin' it! Park

nick s

hudsonkid wrote:

What I was curious of is whether anyone ever did a 4:10 to straight 3:07 swap? results?

better than you got now but not as good as you could do with dropping the overdrive back in.

to put it in perspective
od and 3.07 f.d. = 2.15
od and 3.58 f.d. = 2.51
od and 4.10 f.d. = 2.87
od and 4.56 f.d. = 3.19
od and 3.73 f.d. = 2.61 (parks combo)

standand tranny (or hydramatic) high gear is 1:1 so final drive matches the differential

i've been wanting to build a 2.72 for behind my hydramatic

so a 3.07 would be about half way between o.d. 4.11 and 4.56
od and 4.10 is a nice combo and comes naturally when swapping in an od to a non od car

Nevada Hudson

I put a 3.07 rear end in my overdrive equipped Twin-H '51 Hornet. Makes it run real quiet on the flats, and it keeps accelerating, and accelerating ! I take it out of overdrive when I go up hills. (No big deal !) Much better gas mileage! I think Bill Albright did the same thing. Check out his mileage on the economy run!

Uncle Josh

In the words of Old Stan, the Hudson dirt racer, "RPMs don't hurt an engine, Lugging does"

[Deleted User]

Uncle Josh wrote:

In the words of Old Stan, the Hudson dirt racer, "RPMs don't hurt an engine, Lugging does"

I have 3 of the later Dana 44's with Hydramatic 3.07 differentials. I'm going to put one under the '49 with a straight single lever 3 speed. Before I spend any dinero on swapping ring gear/pinion sets, I thought I'd do this swap and see how it goes. It would probably work better on the single lever, due to its lower first gear ratio. We'll see.



For an OD transmission, I'd say Park has the best combo - 3.73:1.



A hopped up 308, or a stroked 308, could probably run with the 3:58 and an OD.



For anybody running a stepdown and considering a ratio change, I'd seriously look into swapping one of the later model Dana 44 rear ends into the car. As Park said, you can buy any ratio you want brand new for the differential. You can also buy new posi-traction carriers that will accept the 19 spline rear axles. The folks at Reider Racing are very helpful and I would fully recommend working with them on your Dana 44 update.



Mark

Unknown

What's involved with putting a later dana 44 in say, a 50 commodore?



Is this a direct bolt in?

[Deleted User]

hudsonkid wrote:

What's involved with putting a later dana 44 in say, a 50 commodore?



Is this a direct bolt in?

Yep, its why I've been promoting them so much. You'll need the

Hudson Dana 44 backing plates for the brakes, other than that - its a bolt in. Same width, same brakes, same universals, same spring perches, and same panhard bar location.



One call to Reider Racing, and you can get any part you want for the differential including a Powr-Lock of original Dana mfg. That is the same 19 spline posi-traction unit in the Studebakers that Clifford ran in his dragsters.



Phil Harris, of Fairborn Studebaker, also has the ability to supply one piece axles/flanges for the Hudson Dana 44. If you have these axles made with 30 spline ends, you can use any modern carrier you desire in your Hudson.



Best thing is, nobody would even know its modified - unless you took off your hubcap and they noticed the lack of a nut holding on your hub.



Mark

SuperDave

The following is the opinion of the writer and should not be considered to be the opinion of the forum as whole...obviously

There have been a lot of opinions expressed here about the reliability of the early rears. Many are from owners that are making modified race cars out of the stepdown . Nothing at all wrong with that. I did it and probably will do it again. That obvioualy. requires a heavier duty rear end.But as a friendly reminder...

I don't want any Newbys to get the wrong idea. As long as the car is used as it was designed and maintained per factory recommendations.There is NOTHING wrong with the Hudson rear end that was installed between 48 and early 52. The newer differential is an improvement, but hundreds of thousands of early rear ends are still in service. Doing quite well, thank you. Now If you are going to make a race car out of it.. by all means change the rear to something bullet proof. The normal use of a Hudson stepdown will not over stress the early rear end. They do have some WEAK points, but those only manifest themselves when the car is abused by not greasing the wheel bearings, dumping the clutch at high RPM, and running with low or no lubricant. I don't want anyone to think that just because they have an early rear end, that they need to start looking for a replacement or worry every time they drive out of town. Some new owners may think that the rear end is not up to modern highway speed standards. Nothing could be further from the truth. If you have one of the early type, make sure the plugs on the bottom of the axle next to the backing plates have been replaced with grease fittings. Give them a shot each time you change oil and lube the chassis. Make sure the pinion and grease seals are not leaking. Check the level and top off each service cycle. make sure your axle nuts are tight.. Go forward with confidence. Still worried? You can carry a new bearing and race (last time I found one it cost $100.00) or Find an extra used axle and bearing out of a parts car, gease it up, wrap it in rags and put it in the trunk. I have been driving, fixing and fussing over Hudsons since the early 70's and never had a rear end failure of any kind. I did break a few drive line parts when abusing a .040 bored out 51 Hornet with Twin H and 3 speed. I managed to destroy Motor mounts, transmission mounts,center drive shaft supports and one companion flange broke due to a failed ubolt on the ujoint. The axles and rear end are still in service.

I think I learned my lesson! LOL

Having said all this.... If I had a choice of early or late type and I HAD to change my rear end, (not my idea of a fun Saturday) I would choose the later "improved" as long as the cost was similar. So far, because of the unwarranted paranoia surrounding the early rear, I have found that those used parts are very cheap. ..Thank You!

The bottom line is, Ask yourself what you are going to do with your Hudson. If you are going to use it as it was intended, don't worry.. spend your time doing some routine service and drive it.. and yes 70 MPH is fine with properly maintained stepdown Hudson. It was designed for it...My father did it back in the fifties (we survived)and I have done it for many thousands of miles also.

DaveW

[Deleted User]

SuperDave wrote:

I don't want any Newbys to get the wrong idea. As long as the car is used as it was designed and maintained per factory recommendations.There is NOTHING wrong with the Hudson rear end that was installed between 48 and early 52. The newer differential is an improvement, but hundreds of thousands of early rear ends are still in service. Doing quite well, thank you.



DaveW

I'm going to agree with this, and appreciate the wisdom contained therein.



I must say that I haven't any experience with the older type rear end. The only one I have is currently in the '49 and I've never had it out to examine it.



I know the weakness, as is with the later model rear end, is the tapered hub/axle arrangement. The most expensive and threatening thing about the early stepdown rear is the cost of the axle bearings. I intend to play around with the early rear end once I transplant the newer one in.



I have to admit, Dave makes the point that several of these rear ends are out there - and cheap. I'm looking forward to getting one out and being able to put it under the microscope to see what can be done to keep 'em on the road. I don't "hate" the early type, as of yet - I just don't understand it. I've understood the Dana 44's for a long time - and jumped for joy to find out they were original equipment for the mid52 onward Hudson.



Mark

Park_W

I certainly agree with Dave on the matter of robustness of the '48-'51 Hudson axles, and for an OD car the 4.10 ratio is pretty good. If you experience a bearing failure "on the road" you're not likely to have access to a press, so the "axle and bearing assembly" is, I think, what to have in the trunk as a spare. That said, when you can buy a Spicer 3.07 for the cost of a couple of the bearings for the earlier axle, that's pretty appealing. My own (former) '51C8 with 3-speed and 3.07 was really nice on the road, though it required a little clutch slippage when starting out on an incline. I eventually changed to a 3.58 under it. Recently I've driven a '49 coupe with the 262 and 3-speed with 3.07, then later the same car with a strong Hornet engine in it. The Hornet really handles the 3.07 well; the 262 did OK, though of course not as peppy and with a little more throttle required for the hills. Finally, Josh, I can't agree with your statement about RPMs without some qualification. The long stroke "splashers" with soft babbitt bearings are definitely threatened by sustained higher RPMs. But the 4.10 axle with OD is an easy and entirely satisfacory arrangement for them.

Geoff

And another plus for the earlier rear end, they are much easier to do anything with as far as maintenance is concerned. You can remove the pumpkin, put it on the bench and replace the gears. No housing spreader required. No need to take the whole rear end out. And you don't need a press to remove the axle bearings, just a blunt punch and a heavy hammer against the collar of the bearing does the trick. I agree that it's a good idea to carry a spare axle shaft if going on a long trip. I broke an axle on my '50 Pacemaker many years ago, chewed off right inside the spider gear. The later rear ends are much more difficult to change out the gears.

Geoff.

[Deleted User]

Park W wrote:

Recently I've driven a '49 coupe with the 262 and 3-speed with 3.07, then later the same car with a strong Hornet engine in it. The Hornet really handles the 3.07 well.

I'm glad to hear this. I'm hoping my '49 Hornet equipped coupe will like the 3.07. One reason for attempting it was the lower first gear ratio of the single lever transmission.



I love this board.



Mark

Unknown

I have had a dana 44 with 3.07 gears for 4 years in my 33 T8 Coupe. Little shakey being as I have a 9" clutch tho. Now that I am in Iowa its a little more flat, so problem not as bad. But it sure is nice, Of course with a light car and a lot of 8 cylinder torque I can even start of in 2nd gear with no problem as low and 2nd are closely spaced. Speedo is off 10mph.

Park_W

Mark, please note that only the Drivemaster-equipped '49s had the lower first and second gear ratios. Probably done since the Drivemaster mode actually had you starting out in 2d gear. In 1950 or '51 they went to the lower gears on everything, maybe because the cars had gotten a little heavier.

Nevada Hudson

My '50 Commodore 6 once had Supermatic, which was removed by a previous owner. 1st gear is really low. Stump pulling low! I start out in 2nd gear, which does not strain the clutch at all. Much different than other step-downs I've owned.

[Deleted User]

Park W wrote:

Mark, please note that only the Drivemaster-equipped '49s had the lower first and second gear ratios. Probably done since the Drivemaster mode actually had you starting out in 2d gear. In 1950 or '51 they went to the lower gears on everything, maybe because the cars had gotten a little heavier.

Park,



You're right, I really didn't make myself clear. I actually meant compared to the dual lever of the later stepdowns. First and second gear in the single levers is lower than the dual levers. I'm not really sure what the 1st gear in a Drivemaster is.



Single Lever 1st=2.88:1, 2nd=1.82:1, 3rd=1:1

Dual Lever 1st=2.571:1, 2nd=1.684:1, 3rd=1:1



That's all the information I have, and match the transmissions of each type I currently have torn down. The differences in 1st and 2nd in the early transmissions probably help the 3.07 do better in the earlier stepdowns.





Mark

mars55

Actually, the single level transmission came in two different gear ratios. For Drive Master and service replacement parts the ratios are listed above. For cars without Drive Master the ratios are as follows:



1st=2.61:1, 2nd=1.65:1, 3rd=1:1