Hey guys, Need a little help IDing this rear end. Its a 12bolt GM, and a guy in my area has it for sale. I have a 1965 C10 that I'm looking to put discs in the rear. This axle might be the ticket, but maybe not. Through searching, it looks like a '71-'72 is a direct swap, with the later years being slightly wider, which Im sure can be made up with wheel offset. I just want to make sure that this is something I can use, before I throw him an offer. Heres the specs and the pics: Width: WMS to WMS 64" Casting number: 3896839 NF (Passenger side) GM 53 (Drivers side) Looks like the axle was stamped on the pass side HJ1122 Looks like if this is a usable axle from a 71 or 72 C10 that I'll need to weld new perches for the trailing arms.
Yep.. Good point. Could one be fabbed and added? Has it been done? Still wondering what this rear end is from...
4x4s used 6 lug 12 bolts till the early 80s. And 2wd trucks used 5 lug 12 bolts just as long. Leaf springs on all trucks starting in 73.
With no perches on the axle, how can one tell If this is pre or post '73 5 lug? And, most importantly, would, or could this axle be modded to work on a '65 c10? Thanks for your replies btw..
if you do end up using this rearend,you can buy a longer adjustable aftermarket panhard bar that bolts to trailing arm, which is better in the long run if your planning on lowering because you can center the axle which is needed when lowering, and also it limits the side to side movement of the rearend during the motion of travel...cpp, porter built and some other company's sell them. http://www.porterbuiltfabrication.com/showthread.php?261-1963-1972-Fully-Adjustable-Trac-Bar-149 http://www.classicperform.com/Store/1960_1972_Chevy_Truck/CP32021.htm
If it has the panhard bar mount cast into the center, it's 72 or older...if not (looks like it does not) it is 73 or newer. The rear is a little wider than the 65, so you need to run wheels with appropriate back spacing. They got wider in 1970, and went to 5 lugs in 1971.
It doesn't, so must be post '73. I appreciate the easy explanation. I understand that the 71-72 is the optimal swap, but would this be an appropriate rear end for the '65? Considering that the plan is lowering the truck, and with the links that LostHope provided, its clear that aftermarket models can be retro-fitted, and correct offset on the wheels, would this be a good purchase? Or, would it be better to skip this one, and look for an earlier model? The 5 lug pattern and disc brakes is the biggest draw, but I'm tired of creating more work for myself than necessary. As most projects go, I've done that far too many times lol..
The disk brakes don't do much for me...nor do 5 lug wheels...but if that's what you want, and you can add the perches and panhard bar, it could be a decent swap. Make sure the calipers are good and that you can get the emergency brake working, etc. Also check the gear ratio make sure it's what you want. When I had a 66 suburban, the only problem I had with the original rear was the ratio, so I got another rear out of a van with the right ratio, and swapped the gears and carrier into the sub rear.
It is possible that it is an early '63 housing with the panhard bracket cut off, but I doubt it. The bracket was welded to the right (passenger) tube on the early housings and later switched to the cast in mount from late '63-'72. My guess is it is a '73-later housing. There should be a date code in the lower webbing next to the diff cover. It will have a letter, followed by a one or two digit number, then a single digit number, ex.- B 7 5 (March 7, 1975) or H 24 8 (August 24, 1978). if it is an early rear and you cannot tell where the angled perches were or the panhard bracket, it may be confusing as it will end with the number two or three. If it is a two, early '63. If it is a three, could be a '63 or '73. There is also an I.D number stamped into the passenger side axle tube that will tell year, ratio, and diff type. There may be a website you can type that into to get the information. Most of the early '63's still used 17 spline axles (carried over from the '47-'62 dropout style rear) though as compared to the late '63-up 30 spline axles. I hope this helps identify what you have there!
63 would have a panard bar bracket welded to the right axle tube. That bracket, if you can find one from 60-63, can be used with the matching longer bar, when using a 73 up c-10 rear. There is a slight difference in the P-bar "frame" bracket as far as angle and location, but your 65 is adaptable to the earlier parts. Widths: 1970-up went to a slightly wider rear, about 1.5" or so. That actually fills the wheel well better, and does not require different offset wheels. can't find a 71/72 rear? , then: -If you want 6 lug, go with 73-up 4x4 -if you want 5 lug, go with 73-up 2wd I would not buy that disc rear. you don't need discs-I would never put them on a 60-66 and I've modded dozens of those trucks for other people ....and... i don't see that you even know what ratio it has yet? if you need lower number gears, those were more common by the later 70s pickups. Suburbans seemed to have lower numbers more often, especially loaded ones with A/T and full accy's for some reason.
The Jalopy Journal
