Which used rear should I look for? Ford 8.8, GM 8.5 ...?

[crakarjax]

I recently realized that the 12-bolt truck rearend I was going to use on my project is shot. So I started looking around and can't really tell which rear would be best for me. People say that the ford 8.8 is a good fit and I have also seen some rearends out of S-10 Blazers on craigslist. Also saw some members using Impala/caprice rears. I am mostly concerned with the width being correct, but if I am going to buy one I figure I might as well go for one with disc brakes as well.

What models/years should I be looking at for donors? Is there a website with dimensions that I can reference?

TIA

[ChevLoRay]

Rear ends from '60 to '69 are the same width. They got a tad wider in '70.

Do you have leaf springs or coils?

[crakarjax]

I have coils. I have a '72 12 bolt that I was going to put in my '68 so I think that the width difference between my stock 68 rear and the 72 are minimal. I'm looking for 3.08 gears, not sure if that narrows my options down or not...

[crakarjax]

Good info on the Ford 8.8:
http://www.therangerstation.com/tech...plorer8_8.html

[Longhorn Man]

why not stick with a 12 bolt made for the truck?

[crakarjax]

Can't find any, plus I'd rather go to a stock disc/newer rear.

I did find a GM 8.5" out of an S-10 extreme with limited slip for $350. It's about 49" flange to flange but it's drum, which is not then end of the world in any case.

[68Stepbed]

I read in another thread 67-70 rears are 55.5" wide, late 70-72 rears are 57" wide. S10 rears won't work.

If you look for an 8.8, look for them from full size trucks. You can look for a Ford 9", but you won't find any with discs, but kits are more readily available.

You could also look for 99-01 full size Chevy truck rearends. I don't know the widths, but they have disc, but they're also six-lug.

[7T2]

Originally Posted by 68Stepbed

You can look for a Ford 9", but you won't find any with discs, but kits are more readily available.

Ford 9" rear ends out of Lincolns will work, they are the right width, have disc brakes and have the correct 5 on 5" bolt pattern. Not sure what years, but I believe you would look for mid-seventies. I have one of the housings with the axles and bearings, but nothing else. I tried to sell it forever, and finally sold the gears out of it at a swap meet.

[7T2]

http://67-72chevytrucks.com/vboard/s...hlight=lincoln

[crakarjax]

Right on, the 12-bolt in my '72 donor is around 57" wide while the S-10 rear that I just checked out was only 49" wide... should have figured as much since those trucks are so small. So I guess I am looking for 55.5" to about 57" wide.

I'm not looking at ford 9's because I read that they consume ~30hp due to the gear angle or something like that, and also I am not going to be racing or anything, and will have a relatively mild engine.

I would really like to find a database somewhere with rearend specs. I'll look around and post it here if I can find one.

From 7T2's link:
troy54gmc: I researched and found out that the 95-01 explorers came with 8.8 rearends with disc brakes.

I'll follow up with him and see what other details I can find.

[crakarjax]

I found a good writeup on the 8.8 being retrofitted to a TJ, including some fabbed e-brake brackets:
http://www.nwjeepn.com/Axleswap.html

Looks like the width is just about right, plus discs, limited slip, and an easy e-brake install. I'll poke around these forums and see if I can find a writeup from anyone who installed one of these in their chevy.


Door codes:

41 Open 3.27
42 Open 4.10
43 Open 3.08
45 Open 3.55
46 Open 3.73
D4 Limited Slip 3200 3.73
D2 Limited Slip 4.10
L73 Limited Slip 3.73

Axle tag codes:

3L73 = 3.73 LS
4 10 = 4.10 open
4L10 = 4.10 LS

Ford 8.8 specs:

Weight complete: 174 lb.
Axle shaft strength: 6,500 (lb. ft.)
Bolt size (U-joint flange to yoke) 12 x 1.75 x 30 mm

Measurements:

O.D. of tubes: 3.250"
Tube thickness: .250"
Ring gear diameter: 8.800"
Ring gear bolts: 7/16" dia. (qty. 10)
Pinion diameter/splines: 1.625 / 30
Axle shaft diameter/splines: 1.320 / 31
Overall width 59.625"
Hole diameter for ABS sensor in top of housing: .811"
Centerline of housing to C/L of pinion difference is 3.875" toward the P/S.

[crakarjax]

8.8 rebuild:
http://www.explorerforum.com/forums/...d.php?t=144780

[Dave]

Here's another option to think about. At one time a popular conversion was a rear out of a '79 Seville caddy that already has disc brakes and was close in width to the stock rear of the truck. I remember seeing a conversion thread on this a few years ago. Anyone know where it is or have input?

[stich626]

THE FORD 8.8 IS a copy of the 12 bolt..
if you go with that, you can get disc off mid 90's explorers (thats what the SVO disc kit is)
as far as the g.m. 10 bolt chevy rear.. any with the right flange to flange, the b body taxi,cop disc
both have c clips, keep that in mind if your going to the track..

it can't be that hard to find a 70's 2wd ford truck 9" rear
I don't know why you want disc.. are you going to be towing? or is it just for looks

if your not set on wheels, the flange to flange,measurement you have some fudge factor, as the bed wheel houses are big.
depending what your planning (you didn't say) tow/big block power/or just a working rear..?
the 8.8 will be the easyest(read cheap) to get rear disc for if you"have to have it"

[crakarjax]

I'm going to bag the truck eventually, probably 6" drop in back, will probably tow with it intermittently, and since I'm restoring it I might as well go with discs all around, right? I'll have a mild big block 402 and possibly a vortec 5300 in the future, so nothing too powerful.

[crakarjax]

Looks like crown vic police interceptors came with posi 8.8" 3.27 rearends as well. Seems like a good gear ratio for me since this is my daily driver. The Ford 8.8" has a 5 on 4.5" bolt pattern, so the axles would have to be drilled out to accommodate 5x5 wheels.

[crakarjax]

8.8 Build-up article and general comparison of the 8.8 vs GM 12 bolt and ford 9":
http://www.carcraft.com/techarticles...end/index.html

[doaner70]

Rearend out of 90' lincs are disc brake. If you have any guys that rum demolition derbys living around you. We just throw those rearends in the scrap pile. So you could get them cheap. If anyone close to me needs them I can get a crap load of them out of 90's linc and vics. Buddys and I all derby and we just toss them.

[crakarjax]

Old thread I know, but I wanted to update that I couldn't find a suitable 8.8, and came across a solid 5-lug 12-bolt out of a mid-80s truck. I'm going to re-use my housing (coil spring vs the leaf that I got) but use everything else from the leaf rearend. I plan to do a write-up on the rebuild and I'll post it as a different thread when I get it done.