Front axles, whats the difference?

[maddog]

All of you who are so wise in the ways of building hotrods

Being the rooky I am, what is the difference between the many front axles that are good to build with? You know, the pros and cons.

Model T
Model A
Fords
Chevys etc.

It seems as tho just about anything can be used, but maybe some spindles or brakes may be very hard to get or too expensive.

Just looking for a conversation on the general ins and outs of the subject.

Thanks as allways

 

[FlatBroke]

I would like some info on this as well.......

 

[Bonehead]

Your best bet is to get a Speedway and or other good catalog. Look at what is available for what. Usually you start with something. Like the look you want, or the width you want. Or the weight of your ride. Remember the original T axle was on a flimsy frame and had a small motor. It was pretty tuff,but....
Anyway in about 32 when the V8 came out the axles where lookin pretty beefy. Nowdays if you order an axle, you get the choice of bolt pattern, Ford or Chevy. The axle remains the same, usually based on a Ford axle. If you are using and old axle there are new parts available for them too. ( Stay away from mechanical brakes) There is a lot more info to consider, like what kind of brakes, bolt pattern, drop,suspension. Big subject. We have not even touched on modern axles, like a dropped I beam early truck axle or Twin I beam style.

 

[maddog]

Thanks Bonehead.

I have an understanding of suspension in general.
Specificly,
The model t is light weight, correct? When did the T end and the A start.
Advantages of the split wishbone.


I have a 29 or 30 stock Ford axle and a round dropped tube (like you would find in speedway)

How about the later fords say the 40's? pros and cons.

I just wanted to get a lively discussion about what you like and why. I think many rooky ratrod builders lurking and reading would like the education.

I think some pics of the different types for identification purposes.

Here are my 2 axles. What can you tell me about these and why.

 

[maddog]

If I could go on.....

Yes there are plenty of catalogs. I have studied and commited to memory a couple like Speedway motors and fatmans. Thats good stuff. I am more interested in the scrounged, scored, scavenged stuff (Hmmm all S's) that the average fabricator can work with.

I know you all have your preferences based on your experiences. I would like to hear what you found, used and how you did it. What you would do different.

More questions - (conversation starters)(I may have drank too much coffee)

How do you straighten an I beam axle?
How do you drop an I beam axle? Who does that If I cant?
Are certain springs better with a perticular axle or can you mix and match based on your fabrication and engeneering abilities?

 

[donsrods]

Bonehead pretty much covered it. To answer your question about the Model T, it is a weird axle and should be avoided for hot rod use. Weak, and the ends accept NO modern spindles.

'28 to '48 Ford all take the same spindles, so you can use '37-48 spindles and get hydraulic brakes or adapters to put discs on them. The earlier (28-34) have the narrowest spring perch mountings. After '35 the springs started going in front of the axle, and the perch holes are further out. The axles also got beefier as the years went on to accomodate heavier cars and more HP.

By far, the most common hot rod axle is the '28-34 style, with the 32-34 being the most popular out of there.

All that being said, I still think one of the SuperBell axles that is already dropped 4 inches is the best value going. It's new, you can drill holes in it with holesaws, and they sell for about $ 200. Anymore you will pay a hundred or so for a used axle, so the new one just makes more sense, and it is already dropped.

As Bonehead suggested, grab a speedway catalog because it explains a lot about axles, and other stuff. BTW, this is a Superbell under my T.

Don

 

[maddog]

Good stuff Don. Thanks.
How do you identify the 28-34 from the later?
Is there a diminesion I can check to tell?
Were there many different widths (Spindle to spindle) ?
No mention yet of other axles. Are they just too few and far between?

OK, so I didnt commit the entire speedway to memory. I will go back and read more about this. It is getting clearer though, thanks for that.

What about wishbones? How does one tell the difference and which ones are better?

 

[donsrods]

Here is a little chart showing the various Ford axles through the years. I'm not sure of the dimensions of each one, but most are about 50 inches kingpin to kingpin.

All I know about wishbones is that they got better and stronger as the years went on. Model A's are ok, but a little spindly compared to later ones. The ones I always use are the ones where the spring was originally out in front of the axle, then I cut off that extension and use it as a regular wishbone, with the spring either on top or behind the axle.

I'll try to dig up more answers and post them as I can. The reason I have only touched on Ford is because that is pretty much all I have any experience with. I do have a dropped axle under the Dodge (aftermarket tube) that uses '49-54 Chevy spindles, but I know of no stock Chevy axle that does that.

Don

Notice that as the years went on, the perch holes on the Ford axles moved outboard more. Also note on the wishbone the shiny spot on top front where I cut off the extension for the spring in front.

 

[donsrods]

Here, I borrowed this from another forum:



Most of you will find that your eyes will glaze over before you finish reading this, but here is the full scoop regarding the differences between the FACTORY STOCK 35-36 axle and the FACTORY STOCK 37-41 axle.
First, it is important to note that the kingpin holes and the wishbone holes are both angled on both axles. As a result, you get a different measurement depending if you measure them at the top surface of the axle or at the bottom. Bottom measurements are significantly wider. In my description, I'll use the measurement at the top.
The 35-36 axle has kingpin centers of 50 3/8 inches. The 35-36 axle has wishbone pin centers of 36 3/4 inches. (Note: the kingpin measurement is at the top of the axle, NOT the top of the kingpin. Again, that would be different, narrower, due to the angle of the kingpin).
The 37-41 axle has kingpin centers of 48 1/2 inches. The 37-41 axle has wishbone pin centers of 38 1/2 inches.
Now remember, these are measured at the top of the axle.
This would lead you to believe that the 35-36 front track is wider than the 37-41 track. It is NOT WIDER. The reason is that the 35 and 36 brake drums have a smaller offset than the 37 thru 48 drums. This makes the track the same.
If you put 37 thru 48 drums on a car with a 35 or 36 axle, your front track will become almost 2 inches WIDER than stock.
The drop height of the two axles are also different, but this is also not the whole story here. You will find that the wishbones are also different, and that there is a vertical dimension difference between the spring shackle pin and the place where the wishbone rests atop the axle. This though, can be the subject of yet another post.


Don

 

[donsrods]

And this coupe shows the spring in front of the axle, as used on '35-'48 Ford cars.

Don

 

[Bonehead]

The other thing you asked about was setting a larger drop in an existing axle.
There used to be shops that did this kind of work on a regular basis. I can't think of the name but I have seen their work. I am sure they set up a jig and put the axles in a forge and re- shaped them. The old axles were drop forged, which is similar to how I beam and channel iron is shaped hot, but is still mild steel. (If you have a cast iron axle don't try to re shape it.) I think most stock axles have about 2 inches of drop in it from the factory, so a 4 inch drop is really only 2 inches more than stock. You asked how to straighten an axle, I am guessing it is bent. Heat would be the answer.

As far a split wish bones go, totally different from hairpin, (or curtis) vs a 4 link, or 4 bar set up. So we are really talking about 3 different ways to locate the front axle. The wish bone, or bone style is a heavy bar that runs to the axle, and opens into a "c" around the axle at the end, and a single mount on the frame. The split refers to the old factory style which located the frame mounts inward towards the center of the car. the modification was to seperate these to the ouside of the frame. A hairpin set up runs generally the same route but usually goes to a bracket welded to the axle and seperates the front mounts further apart. A 4 bar set up carries the separation at the mount on the axle to two mounts on the frame. These are in order from oldest to newest.
It is a matter of opinion on which is best but most modern set ups tend to go to a 4 bar style. I feel it keeps the axle more straight in a suspension situation.
If I missed on any of these points someone please correct me, as these opinions mine and not copied from anyone, this is just the way I have always understood them.

 

[35Mastr]

Maddog,Here is a site that has alot of info on this with good pics.After you get it up go to the left and you will see the Ford axle info.Just click on it and you will get alot of info that you are lookin for.



roadsters.com

 

[maddog]

Now thats an education!
Thanks all of you for taking the time to post.
I'm sure I am not the only one here that will put this info to good use.

I went to my car club meeting tonight and the first person I asked sold me a 40 ford axle, hubs, spring, and wishbone for $20.

I now have 3 axles to choose from.
I am sure I can split that wishbone and make good use of it.

Love that diagram showing all the axles,Don.

 

[Bonehead]

Something I forgot to mention. The round tube axle is not set up for bones.
The reason bones work is by twisting the I beam style front axle. The flex is part of the suspension. I just got to thinking about this axle info and thought I should pass this on.

 

[buckeyedon]

Maddog, Bonehead

Thanks for the info. Have a few axles now I can I.D. them. Good stuff!

 

[maddog]

You dont have to thank me, all I did was ask another question.
It was all the other brothers with the info.
These guys know stuff. It is good.
I too, like the pic that Don posted. I now have 4 front axles and can easily identify them.

Maddog, Bonehead

Thanks for the info. Have a few axles now I can I.D. them. Good stuff!

 

[sakustoms]

can I use a Ford axle on my 36 chevy PU? It has front leafs now and it seems as though I could get it lower with a ford axle and spring setup with a taller perch.

 

[Bonehead]

Roddguy just posted his front end in the 37 packard build of Rusty wrench. I like that one.

 

[sakustoms]

Roddguy just posted his front end in the 37 packard build of Rusty wrench. I like that one.

I saw that one. That's what I want to do with my truck. The only thing is I really don't wanna swap out brake setups. Maybe I'll just Z the frame.

 

[doghousedevil]

hey don,

how much does this way lower the car? how hard is this to do? i have a '37 axle and springs, and i dont know what year the split wishbone is from. here's a pic of my car so far. we temporarily welded the doors on because it's a chevy and it had fallen to pieces.