what the heck - tried swapping a 71 rear into a 63 c10 and its not close

from everything ive read the 71 rear was supposed to be a direct swap into the 63. NOTHING lines up - not the panhard bar length, and more importantly only 1 side of the spring perch and ubolts. any advice please? i have now spent 2 weekends essentially making a running truck completely inoperable and i am ready to just post it for sale as is. i am peeved beyond belief. everything says the 70 and up are WIDER and mine is somehow narrower. by at least 3/4 inch. but it IS 5 lug. maybe someone swapped the stock one for something else? but this was perfect in the 71 i got. what the heck is going on?

 

well i just did MORE reading and it seems that the spring perches ARE in diff spots. son of a bitch. i should have just paid the damn shop to do it. instead i spent 500 on a c10 chassis, a weekend cutting it apart, another weekend getting the old rear out and the new one in, and now still need to get a pro to weld in the perch mounts. ugh. i thought i was on the right track.

 

You may also look into an adjustable panhard from http://www.earlyclassic.com/catalog.aspx?category=panhard bars

 

Take a break. Have a beer, and then get down to it. You can make it work.

 

thanks all. im ok with the panhard bar - i can either cut it and shorten and weld it with some plug welds, a sleeve, and then a butt weld with my 110 mig. im not sure i trust my welding tho for something as important as the spring perch or whatever its called that locates the axle with the u bolts. i didnt even think if the pumpkin will line up. obv i can line the pumpkin up and see if even 1 side of the perches lines up. if thats the case then i can bolt in that side, and the panhard bar and be confident that i can cut off the other side axle perch and weld in a new one in the right place if my welder is strong enough.

thoughts?

 

Thoughts?

What was wrong with the one that was in it?

 

the 63 had bad everything lol- 7 to 1 1st gear (or whatever granny gear is), bioth drums needed complete replacing, the axle seal(s) were leaking and shot, etc. all in all other than the outside, it needed nearly everything. i happened upon a 71 that i thought would swap right in. i didnt realize/read that the perch mounts wouldnt line up - which is why i went with the 71 in the first place was to avoid that. maybe i have some hodgepodge thing or maybe i just didnt read carefully enough. either way im not getting this sorted without some welding which ticks me off because anytime i try to save money but researching and doing it myself, it costs me 2times as much and takes 10 times as long lol.

 

You will need to move both spring perches, to the same position (distance apart) they were on the original axle. If you only move one, the axle will be off-center.

You can weld the panhard bar with the 110v MIG. For the spring perches, you can tack them on with the 110v MIG, and have someone with a more powerful welder finish them up. Any welding shop can do it, or a buddy, if you've got one with a 220v welder.

Don't forget to set the pinion angle. You can do this with an inexpensive angle finder you can get at the hardware store. Should be under $10:

 

thanks Gimpy - i am way new to this sort of stuff so does the following seem like a good plan:

1 - cut off stock perches on the 71 donor
2 - hook the pumpkin up to the driveshafy and get a jack under it
3 - cut down panhard bar and tack in place and install it to 71 rear
4 - use jack to make sure pinion angle is correct (by the way what IS the correct pinion angle for the 63? maybe 3 or 4 degrees?)
5 - slide new perches on both sides and lightly snug them in place with the ubolts.
6 - tack them in place and bring to a real welder to final weld

by the way how would i look into an e-brake setup for this now that its a mishmash or 63 and 71 bits?

 

Yup. 3º is a good angle. Just make sure you check with the chassis level, and all of the weight on it.

I am a bit fuzzy on the exact parts for the parking brake. I work on so much stuff that it is all starting to blend. I believe that you can remove the cables from the early rear, and swap them onto the later rear, and then just hook them back up.

Pull a drum off of each and look at where the cable hooks to the lever. They should be similar.

 

thanks again. so why does everyone say to use a 71 or 72 to drop into a 63 if the same amount of work to use that is required to use a 73-87 one? maybe i missing something.

 

Just a note of caution...you may already realize this, though, but you DO NOT have to center the pinion yoke when installing the axle spring perches. Lots of vehicles have off center pinions, that's what u joints are for.

You DO want your axle HOUSING centered as mentioned above. As for pinion angle...if you use the angle finder to determine the position of the stock '63 perches, relative to the pinion, just set up the new housing the same way. Just make sure you have both housings sitting in exactly the same position when measuring angles.

Ray

 

You may have a narrower rear. Measure (twice) backing plate to backing plate Check out this site. http://67-72chevytrucks.com/vboard/index.php

 

do you have the 71 trailing arms? can you just swap those instead of changing mounting pads on the axle?

 

trailing arms are all the same.

What I would do is put both rearends next to each other, get them blocked up so they are not going to roll around. Then use the original rear as a model, and make the 71 rear look like it as far as the perch angle and locations.

The parking brakes should be fine with the original cables.

 

What I would do is skip all the swapping of rearend into your truck, and just cut the frame ahead of the trailing arm mount and swap the frame from the '71 into the '63. Then you'll have all the geometry and be able to bolt in a stock '67-'72 rearend or trailing arm if you ever need to in the future.
Might have to fab some mounts for the box to go back on afterwards, but it will be a much simpler swap at the frame than the rearend.

 

Swap the guts of the 5 lug into to the older housing. Measure the flange-to-flange. Same?

 

I put a 72 in my 65, it was a direct bolt in. It is .75 wider per side than the original. You mentioned spring perches, the springs mount on the trailing arms. The trailing arms bolt to the mounts on the axles. I was also able to use the stock panhard bar until I dropped it then I had to switch to an adjustable one. Are you working on a leaf spring rear or trailing arm rear end. I personally have never seen a 60-66 with a leaf rear end. But that doesn't me they don't exist, good luck.

 

Some of the GMC's had leaves.

 

Everyone? No way a 71 will be a bolt in as far as P-bar.

The internet is full of misinformation. They don't realize that the 60-63 had a weld on P-bar bracket on the right axle tube. The later ones had the bar mount cast into the center section.

The bars are totally different length, and run at different angles, which means the L.frame mount for the other side of the bar won't line up right either.


These guys are also huge fans of busting your ass trying to swap in a complete 73 up front crossmember and suspension, just to get discs, and P/S? Huh? The P/S has absolutely nothing to do with swapping in the entire front end, but WTH do I know. You don't need to swap the cross member to get GM truck discs either.

 

If he has a real 63 C10 rear, NOTHING will interchange as far as axle shafts. 63 C10 is a one year only shaft.

Shafts in the 60's for C-10:

-60-62
-63 only
-64-69


in the year 1970, the rear went wider but was still 6 lug on 2wd. In 71, those rears got the new 5 lug axles for 2wd. The 4wd rears had different perches for leafs, but kept the old, 70 style 6 lug, wider shafts.

So, if you have a 70 or newer housing, you can swap from 5 to 6 or 6 to 5, but 69 and older housing cannot use the newer 5 lug shafts because of length.

 

I have a c10 rear end I can get ya info.. Complete 5 lug .

 

Are you sure about that '64-'69 being the same? Wasn't it '65-'69? I think 64 was not a C clip axle, but '65 was. I've got a '69 with 5 lug axles and 5 lug disc brakes. It came this way to me, so not sure if someone swapped the complete rearend, or axle shafts and spindles.
The kits Speedway sells to convert the rear axles to 5 lug are listed as "65-69"
http://www.speedwaymotors.com/1965-1969-Chevy-Truck-5-Lug-Rear-Axle-Conversion-Kit,46263.html

 

F&G is right. 64 to 69 is the bolt in swap. 70 71 is a bit wider. The early (60-63) chassis is different than late (64-66) chassis. CPP makes rear perches for the trailing arms that you can weld to any rear end. I used a ford 9 inch for shits and giggles. There perches already have the trailing arm geometry built in to them(they run at an angle) as I am sure you know by know. Built my own panhard bar.

 

I used a 1973 Buick Estate Wagon rear in my 65 C10. Bought the lower perches from CPP, I think that they were like 30 bucks. Made my own panhard bar mount from 3x3 box tubing. I tool the stock panhard bar , shortened it and threaded it for a heim joint on the axle end. Still working good 70,000 miles later.

 

thanks for everyones insight. i do appreciate it. maybe i just have the 1 year odd truck i am not sure. everything is a learning experience for me so chock this up as yet another one. i really tried to do my homework and get the right parts etc. this truck has proven to me that between me and the internet there is a huge gap. i tried putting power steering on it and that has been a cluster. trying to find the correct pow steering pump and bracket has been fun. now the damn rear axle thing is getting comical.

ive been up since 4am with my son so my brain has been going over this. is there a chance that i can "pinch" the trailing arms together after hooking the driveshaft to the pumpkin? the truck is 60 years old - MAYBE the trailing arms got somewhat tweaked and thats why the pads dont line up? im just trying to come up with something.

i get that the web is full of misinfo but in all honesty i truly think the people on here who have offered me assistance did so with best intentions. numerous people said the 71/72 was a direct swap into the 63 at least as far as the perches are concerned. i know i can get this solved by bringing the axle to the custom shop near me and having them set the pinion and perch mounts etc but i had really hoped to do it myself - hence why i bought the 71 chassis. it will get sorted and i wont trust anyones life to my welding on the axles. im more interested now in figuring why so many people thought the 71 would direct swap? maybe mine is just a bastard year?

 

If you look close at my first reply, I said it was not a bolt in, as far as the P-bar issue.

Now, it's been over 10 years since I got out of 60-66 customer work. I do know that the perches are welded in different total width when comparing 60-62 to the 63-up. That was because the 60-62 had a wider frame.

Now,... I am trying to recall if I ever bolted a 67-72 later body style rearend into a 63-66 as far as trailing arms. I don't know if I did, but if I had to make a bet, I think it "should" be the same perch location.

Have not re-read your earlier posts today; so is it possible someone welded in a different rear end into yours?...and maybe got the locations wrong?

Can you put up pics of your mis-fitting problem?

as far as a 63 being a bummer mongrel, it's not really true IMO. I prefer the 63 P-bar bracket being welded on as a "removable part". That let's you be able to cut that off the 63 and weld it to any 73-87 2wd or 4wd rear to be able to get those great highway gears on the newer ones in that body style....and gives you the choice of 5 or 6 lugs! Towards the late 70s they started using some great gears for MPG, and the center section on those housings were enlarged a lot, to have the "fat" pinion gears to fit. So, it's not like you can use a 2.50-2.70-something ratio ring/pinions gears in a early housing, because the pinion is just too huge.

 

thanks F&J - i think everything on my 63 is stock. the only other idea i came up with is perhaps the 63 is a late 62 and thus the wider frame (possibly). or else maybe i can install the pumpkin into the driveshaft and see if i can "pinch" the trailing arms a bit narrower to get the ubolts and axle pads located? maybe the trailing arms twisted tho i dont think they did. ill check my vin and see if i can find if its a 62 but everything else says its a 63. 12 bolt rear, panhard bar, 283 etc etc.

 

To tell if it's a 62 or 63: 62 had torsion bar front end, but I suppose someone could have swapped in a 63-up front end, but the frame on a 62 would be a heavy X center section. A 63 has a normal looking truck frame without that X.



The possibility of twisted trailing arms: Look at the upper coil spring mounts on the chassis and those should line up centered over the spring mount hole in the trailing arm. I would pull the arms to where they line up with your new rear end, and see if those points now line up.

But if you move the arms to line up to your new rear, and the coil springs look really mis-aligned, then something is wrong.

 

If i read it right, you have a 71 chassis there now? If so, go measure the center-to-center distance on the upper coil spring mounting points on the frame, and compare that to your 63 chassis.



...and if you do have a donor 71 chassis, those 71 discs are a bolt on for your 63. 71-71 spindles are the only disc spindles that use the small taper hole for the earlier small tie rod ends. I believe all you change is the lower ball joint, or swap the lower arms in also. I can measure some 71 spindles here to compare with your 63's. I don't have any of those 63-66 spindles, to see if you really need a longer stud on the lower joint or not, but we could find out by measuring.