1977 rear dig swap

[3X3CrewCab]

Hi all,

First time post, been working on cars since I was old enough to hold a screwdriver. I have a friend who has a 1977 1/2 ton and the rear end went out. It seized the pinion bearing. I starting looking for a new rear end if can't rebuild the one they have. The local yards say 73 to 83 fit. What I'm needing to know and can't seem to find answer is could I use newer than 83 rear end ? I know they went went from a 12 bolt to 10 bolt around 83 but is there any difference other than that? One thought was buying a newer 3/4 ton and switching it over.

Thanks for the help.

Also, I'm in the middle of a 6.0 ls swap of my 1984 crew cab. We I'm done I will post some pics along with I've learned along the way.

[daddyjeep]

If it is a 2wd you can pretty much do whatever you want as long as you have the ability to move around spring perches and shock mounts. You could go with a newer axle to get disk brakes, ford 9" even. With a solid axle truck, there really aren't too many restrictions. The same goes for a 4x4....you obviously have to match the gear ratios. as far as bolt in direct swaps I am pretty sure you could use any square body up to 87, possibly even 90's trucks.

[3X3CrewCab]

Thank you for the reply , I should have added it is a 1/2 ton 4x4. I was hoping a newer axel with the correct gears would bolt in. I was hoping to find a newer suburban that's lifted and we could swap everything over. Also I can use some parts for my crew cab ,win win for everyone.

[aggie91]

The 10 bolt rears that are common in the 82 and new C10 trucks will bolt right in. There my be a difference in the flange for the u-joint, as I am not sure about that. I know that the we did one on an '84, we found a 12 bolt with a posi and put it in place of the 10 bolt that was in it. We took out the axles, unbolted the brake backing plates from the axle flange (never took off the hard line from the wheel cylinder), they bolted right up to the 12 bolt, so we did not even have to bleed the brakes. I just don't remember what we did with the u-joint. I think it was the same one...

[3X3CrewCab]

Thank you for the reply, I will do some checking on the ujoint. I need to figure out the gear ratio. All the places I know to look the tags and stickers are gone. With the pinion seized it's going to a chore to get apart.

[LeesTruk]

Swapped an '86 10bolt into my '80 C10 with a bad 12bolt rear. The U joints are definitely different in size, with the 10bolt using a larger joint. You can most likely find a combination joint that will have the correct two sizes. But I also believe that there may be a difference in pinion location, meaning that the pinion flange could be farther aft on the 10bolt vs. the 12bolt, which could affect the driveshaft length. This, I'm not 100% sure, as I replaced my 2 piece shaft with a new single piece shaft (5.3L/4l60E swap). Also, the 4x4's are 6 lug axles, whereas the 2wd's are 5 lug