Help...will the center section from a 51 Ford car rear end (said to be 3:31 gears) fit or interchange with the rearend from a 51 F-1 pickup? Will the ring and pinion fit? If someone knows or can point me in the right direction to find out I would sure appreciate it. Might be just the thing to take the strain off my old flathead motor and give my beast a little more cruising speed. Maybe I could even keep up with you "darksiders" with the big blocks - not from a standing start to be sure but not getting totally blown off on the highway would be a nice change!

Thanks in advance...Flatheads forever - keep em running!

 

My bad...sorry for the dumb question. I just crawled under the thing and looked and obviously there IS NO CENTER SECTION. Boy do I feel dumb. Every Ford I've ever messed with had a "punkin" but this one (51 F-1) must have the axle I hear you guys call a "Dana". I always thought that was a Mopar term but I'm guessing now it's a style of axle - at any rate it's got a rear mounted cover plate and no punkin. Does anyone make a gear set for this axle with maybe a 3:25? Or are the original ratios all that is available?

 

Yes, they make other ratios and they sold DANA 44's in all kinds of vehicles. Do a Google search.

Another idea is to search this forum for data on swapping a 9" into your truck.

 

I've gotten mixed info on the F1 diff's Latest info was that these are Spicer 41's not Dana 44's and ring/pinion do not swap between the two.

You might do a search on Spicer/Dana and see what you come up with. Let us know what you decide.

I went the 9" route and am very happy with the results. Any 9" out of a 1/2 ton from '57-'72 will swap directly into your 51 and can still be picked up fairly cheap with a wide ratio variety of center chunks.

 

Mtflat my diff is a Dana 44. Dana 44's are as easy to work on as a 9".

 

Tim, can't speak for all the years but the 53-56s appear to have used the DANA 44 according to the parts catalog and shop manual. I've cross-checked the available gear ratios and they match the DANA 44 as well. Course, that could just be coincidence.

Soon as I get home I'll try to look at the earlier years to see what the books say. I'm learning not to trust the parts books too much (thanks Barry), but I might be able to post a couple of pictures of the two rear ends so they can be easily identified.

 

Finally got a few minutes to take care of setting up the rear axle ID info. Check this link:

Rear Axle ID Information

You should be able to find out if you have an original axle, and what type it is. If anyone finds any info on the page that is not correct, please let me know so I don't inadvertently lead somebody astray.

 

Thanks Earl! Pictures are good things. It appears that someone has changed out the axle on my truck from the Ford axle (what it should be per your truck parts data) to a later (54-56) spicer 44. At least it sure looks like the spicer in the picture. I'll have to crawl under it and see what the tag (if its still there under all the "natural preservatives") says about the ratio.

Is this the same thing as a "dana/spicer" that I hear mentioned from time to time or is there no parts interchange between a spicer and dana type rear end? Any info about what ratios were available with the spicer 44s? Probably already on the forum - I'll do a search.

Thanks again! This forum is the best on the web for "newby" restorers like myself and I really appreciate the help!

 

The short answer to your question is that Dana Corporation sells products under the Spicer brand name - they are one and the same. Early on, Clarence Spicer was chief engineer of the Spicer Corporation and Charles Dana was the business guru. The Spicer Corporation sort of morphed into the Dana Corporation, and Dana now sells lots of other brand names like Perfect Circle, Warner Electric, etc. If you are really interested, here is a link to a long and detailed discussion of the relationship between the original inventor, Clarence Spicer, and the businessman, Charles Dana.

Dana/Spicer

 

Great information as always - thanks Earl. And yes, I will take a look at the site you provided as it's always interesting to see how the players in this hobby/industry came to be. Also nice to know that parts are still available for this rear end.

I've always "messed" with the Ford 9 inch but from what I've heard about the Dana rear ends they're also strong and I expect the stocker (Dana 44) under my truck will take care of everything that my flathead V-8 will ever be able to throw at it. So, I see no need to change it out especially if I can get some better suited gears for cruising - probably not a problem & I'll look into it. Thanks for all the help - now I just have to get a shop manual for the later trucks so that I can work on the thing as my 51/52 manual shows a completely different looking rearend.

My shop manual describes it as a "integral housing hypoid rear axle equipped with a semi-floating type axle shaft"... but they never really say Ford or Timkin or Spicer or what. The manual definitely does not show the Dana 44 (and that is what is under my truck) so I can only assume that at some point the original axle "went south" and it was replaced with a donor from a later model Ford F 100.

I'll pick up an appropriate manual from a 53-56 and use that when I change out the ring and pinion.

Thanks again!

 

The 48-52 shop manual is correct. Technically the Dana 44 is a integral housing hypoid rear axle equipped with a semi-floating type axle shaft. Since the 3rd member is part of the case and has semi floating axles. I used my manual to rebuild my '51 axle.

 

Okay...I thought that was the same general type but the pictures in my manual sure don't resemble what's there. They also talk of using a case spreader (???) to get the assembly out and show the same tool in use. Just how hard is this thing to get apart anyway? The 9" "hotchkiss" syle rear end is cake but I have other friends (of the C___Y persuasion) who claim that this style is no big deal either.

The other thing confusing me is the Ford parts manual data that Earl provided didn't mention the Dana 44 in use until the 53 on up F 100s. So is this the correct axle for my 51 or you're just saying that the rebuild data in the 51 manual is sufficient to do the job? I LOVE this hobby! Humbles me by the day but you sure do learn a lot about these old trucks and some of the history surrounding them.

Thanks to everyone for the feedback!

 

Look at the rear of the diff on the bottom passenger corner of the housing it should say 44. I didn't need a spreader. I removed the caps, then the axles and then the carrier rolled out in to the pan oil I had sitting underneath by itself. So remove the axles then the caps. The shop manual worked for me.

 

Many thanks for the feedback - it does have a 44 on the housing and I'll give the manual I've got a try. Wish the ratio tag was still in place - I'll try marking the tire and figure the ratio out as described in another post on this forum.

 

It's much easier if you look at the outer side of the ring gear. It should say 10 47 (3.92.1) or 11 47 (4.27.1). You probally have the cover off and just need a rag to wipe the oil off.