The Stovebolt Site Forums The Shop Area Driveline 1947 propeller shaft

I can now confirm that the 1947 1/2T propeller shaft is a single year part. The oakie bushings being sold do not work for this shaft.
When I ran into this almost 4 years ago on my first 47, I thought maybe it was an anomaly. I had not found any info on that issue anywhere. Now, with an intact original 47 truck, I have come across the exact same propeller shaft issue. I will post more as I work through several options going forward. Hoping this info can save some time for future enthusiasts.

Twin Jimmy's, Does this only apply to the 1947 2nd series GMC's, or does it also impact 1947 2nd series Chevy's too??? Just interested from a knowledge standpoint. I'll be watching for further info.

I am pretty sure it will concern Chevys as well as GMC but my experience is limited to GMC only. I am attaching some pics of my 47 shaft next to a 48 shaft.

On the 47 shaft you can see the diameter steps up a short distance from the end. The 48 shaft(which has the tag on it) has a much longer section which is all the same size. The oakie bushing was designed for this profile. The step up in size on the 47 keeps the oakie bushing from going all the way into the enclosed driveline housing. A seal has to be put in there to stop the trans oil from draining down into the rear end and running your trans and u-joints dry.

Option one was the choice I made the last time I came across this issue. Have the propeller shaft turned down to the correct size for the oakie bushing to work. That was not as simple as it seemed. I had to go a couple towns away to the only shop that could handle that, wait 2 weeks and then pay 200+ dollars. That was almost 4 years ago. I would hate to think how much now.

Option two was proposed that I should just open up the end of the oakie bushing to the proper diameter to make it work. There is one potential problem with that idea which was never fully explored. There are spiral grooves in the bushing and they would be removed when the bushing ID was enlarged. Apparently putting those back in was going to be a problem. I never got that far because that shaft I was working with had a nasty wear pattern with some serious grooves. It would have chewed up the bushing.

Option three was to find a proper seal and bushing, then push them into the housing. After that, cut the oakie bushing in half and use the front end for the u-joint yoke. That could be done but sort of janky, if you will.

Option four I am hoping is going to be the winner. I was given the 48 shaft during the last fiasco but it did not help then as it was 2.25" too short. This was due to the transmission changeover from 47 non synchro to 48 synchro units. I would presume that this makes the 47 enclosed housing a 1 year only part also. The other reason it did not help was because my brain was in a box. I was thinking about this issue when I drove by the driveline shop of Santa Rosa. I called and asked if he could lengthen a propeller shaft 2.25". He sure could. Bingo, back in business. When I got the two shafts side by side, I saw that there are other differences at the other end. Width of the collar and where the internal splines are located. Ugh. The final answer was to take the snout from the 48 and put it on the 47. That keeps the back end intact and correct for assembly. I really feel this is the best option as going forward one could just change the oakie bushing without have to do a complete tear down.

I will let you all know how it ends up. To summarize- if you have a 47 propeller shaft you will need to find a 48 or newer donor shaft to swap the snouts with.

Thanks for coming back and provided such a detailed amount of info on the problem you have come across. Looking forward to seeing how your "solution" turns out!

My 1929-51 Chevrolet Parts Book Group 5.441 confirms 1947 1/2 ton trucks are a one year Propeller Shaft, 65-7/16" long with 17 splines, p/n 3683172.

For comparison;

1941-46 1/2 ton shafts are 61-1/2" long with 17 splines, p/n 3657323

1948-up 1/2 ton shafts are 63-7/8" long with 17 splines, p/n 3694764

Mike B

Here is my GMC shafts one came out of a1949 chev (the oily one)the other is from a 52 gmc .no bump on the early one but both different the newer one is about 1/2 inch longer so that explains why some can drop the tube for changing u joints and other maintanence .i had to take the spring shackles off and push the works back a bit.