Dana 41 to a Dana 44 in a 1950 Ford F1
 

I am looking for information on swapping out my Dana 41 to a Dana 44 in a 1950 Ford F-1.

The truck has the original 8BA Flathead and 3 speed transmission. The Dana 41 has a 3.92 ratio rear end. The truck has 15" wheels. At 2500 RPM. its going 41 MPH in high gear.

I have asked around and have been told that gears for a Dana 41 have not been made in years that I need to swap it for a Dana 44 which has an abundance of ratios available.

Does anyone know the closest rear end from another car or truck I could get from the junkyard to make this swap. I would like to a rear end that fits with a 3.00 ratio but if I have to change the ratio I can. Getting the rear end to fit is my main goal without a lot of modifications.

Any he;p will be appreciated.

Depending where you live, I have a Dana 44 out of a 54 f 100 you can have. It has 3.92 gears, I went to a 4.27. I'm in southeast PA. Dennis

You must have very short tires? With 28" tires, 2500 RPM and 3.92 gears, you'd be at almost 55 mph.

Using the later ('51-on) D44's still requires putting in a new carrier to get lower than 3.92, total cost gets up to more than $500. You can get a D41 from another 48-50 with the standard 3.73 ratio, usually pretty cheap, and get a decent reduction. Consensus on here is that a Flat V8 with 3.50 gears is a good place to be. With 3.0 you'd burn your clutch up taking off from a stop, and have to slip the clutch going around corners in 2nd.

Thanks guys for the feed back. I am new to the forum and appreciate the response. I originally posted (by mistake) to another thread about "1950 Ford F1 Axle and Gear choice" and got a great web site for a article published in 2004 by the forum users as a group that has worlds of information on what I am looking for.
https://www.ford-trucks.com/articles/...rential-swaps/

According to the article, the 57 to 72 F100 works best with the (5x5 bolt pattern) I plan to contact the junk yards and put a wanted on craigslist for one of these rear end assemblies.

This rear end fits but what the article did not say was what ratios were offered in these F100 truck rear ends. Does anybody know and were there different ratios for these model years? As I stated earlier, according to a calculator I found online a 3.00 ratio is what I need . Someone said this is to high and would slip the clutch. One reason that they may be mistaken is that the tires have been replaced with P225/75/R15 tires which are smaller than original. Anyone have a thought

I'm running P235/75-15's, which I have measured to have a 28.1" rolling diameter. If you haven't measured your tires' diameters, do it this way: mark the bottom of the rear tire and on the pavement next to that mark. Roll the tire forward one revolution, and mark the pavement next to the mark on the tire again. Measure between the two marks on the pavement, then divide by 3.14. That is the most accurate way to get your rolling diameter. You'll likely get a very different answer than the many charts on the internet!

Stock flathead V8's want to be between 2200 - 2400 for extended highway use, depending on whether you live where there are hills or not. They are not powerful enough to pull low-number axles at highway speeds because of wind resistance, unless you aren't climbing any hills or accelerating. With a 3-sp, you can't really drop down to 2nd for a hill unless you drop speed way down too.

Assuming your tires are about 27.5" rolling diameter, here's what different ratios would put your RPM at.

225/75R15 tires are about the same diameter as the original 6.00-16 tires.

3.00 may look good on paper, but it will not drive worth a darn unless you are driving in very flat area and only on the highway. As stated above, a 3.50 ratio is about the best all around option for a flathead.

edit: ALBUQ F-1 beat me to it, and with better information.

Thanks ALBUQ F1,and 38 coupe, with a 2000 to 2400 rpm and a 55 mph road speed looks like the 3.25 would be the best as I get above 55 mph the interstate and at 2185 at 55 mph I could get a little faster and still not tax the engine to much Do you'all agree?

too far away, I am in Georgia but thanks anyway

Welcome to FTE! :-wink

It's always helpful to others on here to be able to see where you're located and what type of truck you have while reading your posts. You can add those things by going to the User CP > Edit Your Details and Edit Avatar and Edit Signature.

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If your engine had the power to pull it, sure, a 3.25 would allow higher cruise speeds at a relaxed RPM. But it really doesn't have the power.

Ross looks like u have the same engine I have with 3 on the tree. What ratio are u running

I sure do appreciate the feedback the forum has given. Here is where I am: I called around to many junk yards in my sof Georgia and asked if they had a dropuot rear end for a 57 to 72 F100 and all were no except one. It happens to be in my home town of Peachtree City. They want $250.00. I asked what the ratio was and he said it was a 3.25. I am now unsure if the 3.25 will be too high given what you'all have said. I did check my tires and they are 88" around or 28" across. I guess the 28" is the number I need to use.

I would appreciate more feedback on the 3.25 ratio before I pull the trigger on the purchase. I did check on Dana 41's and no one has one either junkyard or specialty drive train house has a 3.72 gear for a Dana 41

That brings me to the other delima. I will ask the junkyard to save the spring shackle bolts and the emergency brake cables but I understand the shock perches are different. The are smaller on the Dana 41 but the quesion if I get the shock perches off the Dana 44 which is still in the truck will they work with my 1950 F1 truck? Also I have heard that the drive line on my truck will be one inch to short. If I get the drive line out of the donor truck will it work?

I am looking for information on swapping out my Dana 41 to a Dana 44 in a 1950 Ford F-1.

The truck has the original 8BA Flathead and 3 speed transmission. The Dana 41 has a 3.92 ratio rear end. The truck has 15" wheels. At 2500 RPM. its going 41 MPH in high gear.

Are you seeing that RPM on a tach? If so, your tach is off by a fair amount. Or your speedo is off, actually more likely. With a 3.92 and 28" tires you would be going almost 55 at 2500.

That's a pretty pricey axle, and any axle that old is likely to need some rework. Like said above, most people find the 3.50 is the best choice.

You don't need the e-brake cables from the donor, and you should always use new U-bolts. The donor's spring plate will be for wider springs, so you need different ones. If the donor driveshaft is longer than yours, yes, I'd get it.

DArn it think I will just keep what I have for now.