Please let me know if you know for SURE what rear ends are stock for 1954 F-100's. Please let me know HOW you know this (owned one, read it in a specific manual, etc.) Please let me know how you can visually identify these rearends. Also: what 1954 rearends had the cover and bolts on the backside? Thanks. (I have not yet found a rearend shop that knows what rearends are stock for this year, they only deal in the last 20 years or so.)

 

The rear axle prior to 1957 was the DANA early version of today's DANA 44 used on some 4x4 front ends. It can be identified
by the removable rear cover plate. Internal parts are serviced from the back. There are 10 bolts attaching the cover plate and there is a drain plut in the plate. Typically, ratios are high, like 3.92:1 or so depending on engine and year. Changing ratios is not as easy as on 57-87 or so axles that were called Ford 9". To change ratios, some of these also require changing to a larger carrier. On the 9", the cover plate does not remove and the center section is removable from the front so you can swap the entire center section (pig) to change ratios. I have owned a couple F-100's with the Dana axle and have run over 300 HP without any problems. Basically the Dana is a good axle. On mine, I switched over to the 9" to get a locking rear with ratios that can be swapped easily and to be compatible with a rear disc brake kit I installed. Further confusing is the range of Ford axles that might have been swapped into your truck. Some cars used a 8" axle and newer cars and trucks used a 7.5" and 8.8" axle that is similar to the old DANA design. If your axle is original, it would the the DANA.

 

According to my set of Ford parts books, there were 4 ratios availible. There rear was a Dana series 44 as listed in the previous post. The 4 ratios are: 3.92 to 1, 4.29 to 1, 4.09 to 1, and 3.73 to 1. In my experience as a Ford parts man for 20 years, the way I read the listing is there was a early and a late rear end. They both were Dana's, as you can interchange all the ratios I've listed. Initially, the 2 ratios were 3.92 and 4.27 . The later had the 4.09 and the 3.73, plus the early 2 availible to the customer. Unfortunately, they don't give a breaking point as to when they changed to the later rear. If you needed a new housing back then on say a 52 F-1, you got a housing for the later rear end. The guts would interchange. Is there a tag on your rear cover? You need that info to look in the parts books. You have to have experience as a Ford parts man to really understand what they were saying in the books. It's not cut and dry.It's a very easy parts system to master, unlike GM and Chrysler, but it has it's quirks!! Hope this helps. Barry

 

[updated:LAST EDITED ON 11-Jan-02 AT 06:07 PM (EST)]Barry,

I've got the following Gear and Pinion sets listed as available NOS for the F-1/F-100:

Year(s), Gear Tooth Count, Ratio, Part Number
---------------------------------------------------------------------
1948-1950, 41/11, 3.73, 8C-4209
1948-1950, 43/11, 3.91, 8M-4209A
1951-1956, 47/12, 3.92, 1M-4209A
1951-1956, 45/11, 4.09, AB-4209D
1951-1956, 47/11, 4.27, 1M-4209B

These seem to be close to your parts book numbers except the 4.27. Is that supposed to be 4.29 or is my info off?

Don't most of rear end housings have a tag (unless it's been removed) stating the actual gear and pinion tooth count for the gears that are installed? For example, mine has a tag that says 41/9 for a ratio of 4.56 (Mine's a 1956 F-250).

Earl

 

I've checked again in the 3 different set of books I have and they list the sets as exactly as you have listed. They don't show a 4.29 for the F-1 or F-100 series. Yes, all Ford rears are supposed to have a tag on them. Either on the covers with a bolt, or on removeable chucks (9 inch) on a stud. Most likely over the years people don't put them back. Also Ford has a habit of coming out with a whole bunch of different parts and superceding them dowm to a few. The 3.91/3.92 ratios were most likely superceded to the 3.92 for a example. It goes on to this day.

 

Gentlemen: Thank you VERY much for this information! I really really appreciate it! I was asking around before this and getting a lot of guesses and getting nowhere. I found the specs plate on my truck ( havent owned it that long) and it says the rearend ratio is 3.92, which certainly seems to match up with the Dana mentioned, unless Ford also made a 3.92.
Any idea what sort of top speed, or regular cruising speed, is reasonably possible with this rearend and a Chevy small block V-8 in front of a turbo 350 automatic trans? Basically, I wonder if I will be able to drive on the highway with the other traffic without having the engine at 5000+ revs all the time. As this truck is down for some engine repairs (got it that way, including with the Chevy engine trans combo)) I have no idea what it will be like to drive with this combination. I dont know if the fellow who dreamed this combination up actually drove it to work, etc. or just wanted to race from stop light to stop light, but thats how it is. Sure, I want to be able to be fairly fast off of the line, but I also want to be able to drive it more than on just weekends.So...while I am saving up for engine parts, I am wondering if I shuld look at possibly changing to that 3.73 Dana instead of the 3.92 I seem to have, for better gas mileage, but I dont want to put the performance in the toilet. Any thoughts?

 

When I bought my '51 it sill had the original 3.91 gears.(evidently a Dana 44) I run a 302-2bbl. w/ automatic, fairly stock (but not for long). Drive it every day.

 

Eric - How is the truck at highway speed with this rearend? Is it maxxed out at about 60mph? What top speed is with that 302 and that rearend ratio? Would you change it for something else, and if so why?

54guy

 

Sorry that I can't give you alot of the information that you are after.....I haven't put a tach in, yet. However, on the highway, I run it up to 60-65 mph without it screaming. I usually stay off of the highway though, and keep the speeds down over long distances. Not because of the gearing......I need 2 rebuild the steering box. I have 2-3" of slop and no more adjustment. But back to the rear......I plan on keeping it til it blows. I have no complaints. I hear parts are high dollar and tuff to find, so when it goes out, maybe a 9". I'll cross that bridge when I come to it.
Sorry this is so long, but I guess what I'm getting at is, if your gears are turning - I'd keep 'em.

 

54Guy,

If you decide you do want to change ratios the info in my earlier post is straight out of the JobLot Automotive (718-468-8585) catalog. It says they may not have all the gear sets in stock but those they do have will be unused NOS for $250 per set. That is still some $$$ but not a king's ransom.

Keep in mind that you can only go down to 3.73 with stock parts so starting with your 3.92 set you'll only see a 5% (3.92 / 3.73 = 1.05 approximately) decrease in engine RPM at any given speed. For example, if you're running 3000 RPM at 60 MPH then changing to the 3.73 ratio will only reduce your engine speed to 3000 / 1.05 or about 2850 RMP at the same 60 MPH. This is just an example but you can plug in your numbers and see what different ratios will do at different engine speeds.

Let us know what you decide to do and how it works out. Happy trucking!

Earl

 

I had the original 3.92 rear in my 53 with a c4 and 351c. Most people, including myself, are used to newer cars and trucks that seem to cruise effortlessly down the road. If you are expecting this with that rear gear, I can tell you you will be disappointed. It does rev high, but it will not blow the engine. Have you ever driven an automatic where you had to push on the gas going downhill? This is what it will be like. And if you have the idle set a little high, and stock non-power brakes, the brake pedal will require alot of effort to keep the truck still with the stock torque convertor. On the other hand, if it will be a playtoy, with stop light to stop light runs, it can't be beat. Tire spin is hard to control and it will chirp the tires when the auto goes into 2nd gear (shifting automatically). It's all in what you want. If the engine will be all hopped up, and you put a stall convertor in the trans, the 3.92 gear will be what you want. If you want to drive it on a long trip or everyday on the interstate, you won't want it.

By the way, for comparison, I used the stock plastic speedometer gear and cable that came with the c4. It was calibrated for the 73 torino rear gear/tire size it came out of. I retrofitted this to the original 53 speedometer that was calibrated for the original gear/tire setup in 53. The speedometer would read 75 mph when I was doing 55 mph. It is a big difference. I bet the torino had a 2.80 or in that neighborhood gear in it.

 

If you want to get that speedo to actually read 55 and not 75 when you're going 55, you need to get a speedo gear with 1-2 more teeth on it, than what is in there now.. Pull the cable from the C4 tranny and count the teeth. Most dealer stock some of the gears or can order you one. They run 7-10 bucks.Adding a tooth equals around 10 MPH.