rear end???

my rear end in my 66 has a lot of slak in it ,what would be a good rear to be looking for to replace it?would be nice if it was a little narrower too.

how many bolts in the cover,,,10 or 12,,,,,,,,,


https://vintage-vans.forumotion.com/t49513-12-bolt-axle

I know it like going to the dark side , but I have a 66-67 econoline 9" ford rear under my 64 gmc. It was a direct bolt in all but the shock mounts needed to be moved. I just cut the mounts off of my 10 bolt and welded them on. Best part is the rear is 1" narrower on each side. Bad part is the bolt pattern is small ford 5 on 4 1/2. I just bought the ford pattern for my rear wheels

What is the drum-to-drum length on our stock rears? I just did a quick check with a tape and it looked about 65"..... Is that right?

Update: re-measured a little more carefully ...... 64 1/2"

Sounds about right.

Track width is 61.5" / 62.5" for front / rear axle.

Add in another brake pad plus some thickness for the drum and that will land you at 65"-ish.

I found that the mounting-face to mounting-face distance (64.5") is exactly the same as the rears in 1991-1996 Gm wagons (Caprice, Roadmaster, and Custom Cruiser)......
What is significant about this is that more than half of these wagons had positraction and it's easy to determine the ratio and posi by looking for specific codes on the SPID sticker in the tailgate jamb....
On the downside, these wagons have a 5on5 lug pattern and four-link coil suspension, so they aren't a direct bolt-in.....
I just bought a complete, good running Olds Custom cruiser for $800 to get the complete drivetrain out of for my van. It's got a 305 TBI roller motor 323 posi, and 700r4 trans....I'll also get the complete wiring harness out of it, as well as power windows and door lock solenoids (great as door poppers!)
I already had some cool 15x10 American 200s daisy wheels, so I'm not sure whether to use adapters, get the axles re-drilled, or slot the lug holes in the wheels for dual pattern....
$50/pair for adapters seems the easiest way to go, but I'm not sure how safe....

Yech, I am very much against adapters since most of them are aluminum. I would not trust them for pure strength.

Hm, good to know that those axles are bolt ins size wise. Too bad you'd have to weld up new perches and shock eyelets though.

azdon your in luck , check out the 4 door sedans of that era. I know that in the 80's early 90's the caprices(2 and 4 doors) where small chevy 5 on 4 3/4(like our vans) while the same caprice wagons where the 5 on 5" pattern . Not sure why they did this , but you might be able to find a non wagon and steel the axles. I ran into this years ago with demo derby cars
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i'm pretty sure that the van rear end center sections are offset to the passenger side, to keep the driveshaft in a straight line with the offset engine placement. be sure to check this before you go too far.

The yoke is 1" closer to the right framerail than the left, meaning it IS offset 1/2" to the right.....The engine/trans is 2" closer to the right meaning that it is 1 inch off-center.......I'm going to move the engine back 18" and was going to center it, although I'd be willing to consider compelling reasons why I shouldn't.....

I moved mine back 8" and moved it 1" closer to the driver side. I have a side mount supercharger on my ls engine and it was sitting where the pass seat was to go

diamond dave wrote:i'm pretty sure that the van rear end center sections are offset to the passenger side, to keep the driveshaft in a straight line with the offset engine placement. be sure to check this before you go too far.

I've read this same thing here before, but for the life of me, I can't figure out why this is important.

As far as I know, the important thing isn't for everything to be lined up exactly, but instead, that the shafts at each end of the driveshaft....the c/l of the tranny output shaft, and the c/l of the rear axle input shaft, are "parallel" with each other.

...you know, looking at the side, if the tranny output shaft c/l is at a 10° angle to the ground, the input shaft on the rear end should be at a 10° angle to the ground. (Which is why they sell tapered shims.) Same with looking at it from overhead....assuming the engine/tranny c/l is centered front-to-back between the "frame rails", and the rear axle is installed properly, squared to the "frame rails", it shouldn't matter if the pumpkin is line up dead center with the tranny output shaft, it's offset an inch or two either way.

Isn't that what u-joints are for?

(I often wonder what some people are thinking when they swerve to avoid a very small anomaly on the road, like a 1/2" high ridge or something....I mean, the car has suspension...that's what suspension is for. Obviously running through big potholes is undesirable, but a bump that can barely be felt?)

The engine is a full inch to the right while the diff yoke is only half an inch to the right....It is CRITICAL only that the engine/trans centerling runs parallel to the chassis so that the phasing angles of the two u-joints (as viewed from above) are the same. It is the same "phasing angle" rule that applies to the horizontal angles of the crank/ trans shaft relative to the pinion shaft centerline.....There is certainly nothing wrong with having all shaft centerines absolutely centered in the vehicle, but it is interesting to note that GM intentionally offset them by half an inch.....

I'm one of those people that avoids un-smooth road surfaces.....violent deflections are REALLY hard on today's crappy tires..... It would be nice to actually wear a set of tires out (like in the good old days) rather than lose them to separations........