The Stovebolt Site Forums The Shop Area General Truck Talk How to date a C10 truck from just the frame and engine

I found an axle at the junkyard from a C10 truck that I am more than likely going to purchase for my 54 3100. I'm sure the axle will work for me but it would be nice to know what year it is from if and when I ever decide to buy a ring and pinion. It has independent front suspension and coil over shocks in the rear. It does have a removable third member which to my knowledge is not very common in Chevy axles but I could be wrong. All that is left of this truck is a frame, axle, and engine. Is there a way to tell what the year of the truck is? I already looked for the numbers on the axle and I cannot make them out.

Thanks

The frame (driver side just aft of the steering box) should have a vin. x frame?

Is the IFS coil spring or torsion bar? I believe torsion bar suspension was used from 1960-63 or so? I'm assuming you're buying the rear axle, right? IFS started being installed in 1960, so it's somewhat newer than that. Coil-over shocks would have been an aftermarket addition, such as Gabriel Hijackers, etc. not original equipment.
Jerry

X-Frame with IFS and Torsion bars = 1960-62.
Ladder Frame with IFS and Coil springs started in 1963.

Apparently the GMC trucks did not have the VIN stamped on the frame. Yes, torsion bar front suspension and the X-frame for 1/2 ton trucks for 1960-1962. Then in 1963 they started coil spring IFS and ladder frames. GMC 1/2T trucks had leaf springs in the rear. Chevy used control arms with rear coil springs (up through 1972 I think).

Yes its the rear axle I am after. I want to say its coil over shocks in the front as well but I didn't get a pic of the front end. I will have to go look again at it next time I m out that way. How exactly do you tell a ladder frame from an x frame? Any one have any good sources for ring and pinions for these axles. From my research it seemed like the later 60's axles are much cheaper and easier to find than the early 60's. If I remember right there was some year I looked up the only ratio they listed was a 3.38. I guess that would be ok but I was hoping to get closer to a 3.50 if possible.

Thanks again

If you see anything that looks like a big "X", it's an "X" frame. If you don't, and it looks like a ladder, it's a ladder.
As you know, it doesn't really matter. Drop outs are 55-64.

Coil over shocks is the wrong term. It is coil or coil with control arms or leaf. They did not use coil over shock. They did not have a coil spring with a shock in the center. I personally would pass on a drop out rear. You may have trouble finding the ratio you want and other internal parts. They have a greater leak path area. Go more modern 10 bolt, 12 bolt, D44. The diffs are usually dated. Got to clean and brush and scrape and search the internet. Whatever you get you will have some fabrication to mate to the 54. The width is important. WMS to WMS should be close. Number of lugs is important.

Any diff that you don't see and hear run has to be cheap. Free- $200. A junk yard is not where I would go unless it's a good old boy type. Check local Craigslist. Take off the drums and the diff cover to inspect the brakes and check each tooth on the ring and pinion. Spin it. The ring gear IS marked with the ratio. You could spend $600 more on a rebuild easily.
As the guys have said: Torsion=60-62. IFS and drop out= 63-64.

Ok simple enough. I had to google a ladder frame because I have seen very few of them. This truck is definitely an X frame. By drop out I am assuming you mean third member that comes out? I was told non drop out Chevy axles take a special spreader tool to get the axles out and are expensive and a pain to work on. Is there any truth to that?

I was trying to stay as original as possible but I cannot find the parts I need to connect to this torque tube axle. The axle I found is the correct width and lug pattern which it why I liked it. The 6 bolt lug pattern is not easy to find. I am starting to think maybe I should go a couple inches narrower and plan on using a 5 to 6 lug adapter plate, which would put the wheels to their correct width. The C10 axle looks like it may work with the original 54 brake parts that I already have purchased. Another fear I have is going with a much newer axle you will probably have different volume wheel cylinders. If I do that I will probably need a proportioning valve to balance front and back braking. Not a huge deal, just more time, money, and further away from originality.

Please take what I am about to say as one man's opinion with some experience. See comments below and in red in your quote.


If you have torque tube you need to wait for advice from AD folks as to what is involved with a different differential.
Yes, if by third member you mean it drops out the front, it's a drop out. If a drop out is the originality you want, use a drop out that' from TT.

Why are you needing a new differential? Can you salvage the old or re gear? I missed that part. Seems like you are doing what many have done. Buy an old truck made for hauling on yesterdays highways and want more speed.

There are probably GOBS of info in our search function regarding replacement diffs for 54. Lederman and others know this stuff.
I have found and swapped a few diffs in TF and have rebuilt a 1960 Dana 44. Not much AD knowledge except what I read. If I remember it all correctly.

Jonald posted: "I thought 54 was open? "

No, all the 1954 3100 models had enclosed drive-shafts.
All models higher than a 3100 had fully open driveshafts in 1954.

TC, my apologies. I forgot to red that comment. I fixed it now. It's me not Jonald. Also I was typing when you posted and knew you would respond.
So it's 55.1 that has 3100 open?

Here is a discussion involving using a powerglide car 3.54 diff with 6 lug axles.

Another note, you may have to modify the length of your whole TT (Torque Tube) with this swap. I understand that "Mother Trucker" may have a ring and pinion set that you can install but I also read it's only for up to 53???

I always say this with the understanding it's not universally accepted. ....... Get rid of the torque tube and go open. Different trans required. It's really not that hard or expensive with donor parts from a running donor.

No need to apologize, Bartamos

All's well that ends well. I am finding that I am now posting more corrections/clarifications these days.

Yes, the 1955 1st series Advance-Design truck had an open driveshaft.

Don't forget the 'modern' GM sf 14 bolt with 6 lugs, might be too wide, however. Came on light duty 3/4 ton trucks.

Ed