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Flathead Smith · 07-10-2020, 12:36 PM

To remove the third member you only need to:

1. Drain the gear oil.
2. Pull the axle shafts out about three or four inches... yours are already removed so no big deal.
3. Unhook drive shaft from axle.
4. Put an automotive floor jack under the third member.
4. Remove the 10 or so bolts on the opposite side of the differential cover.
5. slide out the complete third member and drop down.

It is one of the easier axles to work on.

Finding the 4:11 third member will be your toughest part, but if you do, the install is easy.
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As far as the Dana 60 goes, they were supposedly used in C20s from 1964-72. They were used in both coil spring suspensions (like yours) and leaf sprung suspensions. I originally was under the impression they were only used in big block trucks, but I saw one under a 1967 C20 with leaf springs that was a stock install.

The Dana 60 is a bolt in affair, if you get one out of a coil spring truck and you have the pan-hard rod that come with it... with the possible exception that the drive shaft may need to be modified. If you use the leaf spring version you will need to remove the leaf spring perches and use something like one of kits shown in my previous post.

The great advantage of the Dana 60 is that all parts are readily available, as it is still produced today and it will have the greatest selection of gear sets and differential options.
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There is another option and that is to use a A833/NP833/MY6 transmission in place of your four speed (most likely a Muncie SM420), or one of the more modern 5 speeds used in 1988 and up year Chevy/GMC trucks. The more modern five speeds will have a good gear spread and have an overdrive, which will turn your 4:56 into a ≈3:30 in OD, and really may be your best solution.

About two years ago I went looking for a A833 and actually found two on the same day. The A833 transmission was found in 1980-87 Chevy Trucks/Vans/Step Vans. The aluminum cased version of the transmissions was used for sure in the 2WD 1/2 ton with the gasoline engine. The cast iron version was used in the 4WD (MM7) and Diesel 3/4 ton version (and possibly the 1/2 ton diesel version also). I was able to get both the 2WD and 4WD cast iron version, which I prefer.

07-10-2020, 12:36 PM	#22
Flathead Smith Registered User Join Date: Aug 2011 Location: DeArmanville AL Posts: 47	Re: KS10 rear end To remove the third member you only need to: 1. Drain the gear oil. 2. Pull the axle shafts out about three or four inches... yours are already removed so no big deal. 3. Unhook drive shaft from axle. 4. Put an automotive floor jack under the third member. 4. Remove the 10 or so bolts on the opposite side of the differential cover. 5. slide out the complete third member and drop down. It is one of the easier axles to work on. Finding the 4:11 third member will be your toughest part, but if you do, the install is easy. ------------------------------------------------------ As far as the Dana 60 goes, they were supposedly used in C20s from 1964-72. They were used in both coil spring suspensions (like yours) and leaf sprung suspensions. I originally was under the impression they were only used in big block trucks, but I saw one under a 1967 C20 with leaf springs that was a stock install. The Dana 60 is a bolt in affair, if you get one out of a coil spring truck and you have the pan-hard rod that come with it... with the possible exception that the drive shaft may need to be modified. If you use the leaf spring version you will need to remove the leaf spring perches and use something like one of kits shown in my previous post. The great advantage of the Dana 60 is that all parts are readily available, as it is still produced today and it will have the greatest selection of gear sets and differential options. ------------------------------------------------------ There is another option and that is to use a A833/NP833/MY6 transmission in place of your four speed (most likely a Muncie SM420), or one of the more modern 5 speeds used in 1988 and up year Chevy/GMC trucks. The more modern five speeds will have a good gear spread and have an overdrive, which will turn your 4:56 into a ≈3:30 in OD, and really may be your best solution. About two years ago I went looking for a A833 and actually found two on the same day. The A833 transmission was found in 1980-87 Chevy Trucks/Vans/Step Vans. The aluminum cased version of the transmissions was used for sure in the 2WD 1/2 ton with the gasoline engine. The cast iron version was used in the 4WD (MM7) and Diesel 3/4 ton version (and possibly the 1/2 ton diesel version also). I was able to get both the 2WD and 4WD cast iron version, which I prefer. Last edited by Flathead Smith; 07-10-2020 at 01:18 PM.