I sent you a PM about a rear end I have available.

 

The easy answer is a 9 inch Ford.Check Ebay there are companys that sell housing /axle kits that are prenarrowed to the width you want,and have 55-57 spring perchs welded on.Add a center section,and what ever brakes you want including discs.Pretty bolt in if not the cheapest.Low buck if you have the skills to do it,8.8 Ford explorer.Might need narrowing.Will need spring perchs welded on.Comes with drum,or disc.

 

Wow, how things have changed. Put a Ford rear end in a Chevy? Sacrilegious. How much money do you intend to spend because upgrades are not cheap. If you absolutely need a bullet proof rear end for a Chevy, check out Fabcraft Metal Works. They have Pontiac units available. Not cheap but, you should compare to those offering bolt in Ford units. Ford differentials have a geometry issue between the pinion and the ring gear and that necessitated the third bearing on the pinion shaft. If you are not drag racing, just an occasional "burn rubber" addict, why not look into a solidly rebuilt Chevy posi unit with 4:56 gears. Bad on gas but absolutely fun in the seat. I have 4:88 backing up my Muncie and my 265 = 7200rpm.

 

The simple truth is that GM 10/12 bolts will run you just as much as a stronger Ford unit. Period. And, that Ford unit will have better support for disc brakes, especially in the case of a 9". If they were so bad, they wouldn't be the choice of hotrodders that have Chrysler and GM cars, as well as FomoCo builds. If you can find a good 8.5" 10 bolt, that's a decent option, but in most cases it'll need a complete rebuild, it'll be an open diff, and it'll have a bad gear ratio (like a 2.56 or 2.73). You'll put a lot of money into rebuilding one unless you can find a good donor and even then, it may need to be narrowed. Forget about a 12 bolt...they cost a fortune.

As far as the Olds/Pontiac rearends go...good luck finding one. And if/when you do, because they're so rare, you'll spend some serious coin on a rebuild, a decent set of gears, maybe axles, posi, and disc brakes will be spendy too...probably well over $3K. That's just to get it to the point that a stock Ford 8.8 out of an Explorer is already at (can be had for about $300 with 31 spline axles, limited slip, disc brakes, and a good gear ratio for a hotrod like 3.55's, 3.73's, or 4.10's). I have an 8.8 behind a 600HP 420ci SBC. It'll be fine behind a 400HP motor.

A Ford 9", bolt-in, can be had for about $2K from Quickperformance.com. Pull the old one out, drop the new one in. Sometimes, convenience is worth money too.

Honestly, if you have an auto, a posi in a stock rearend might be ok too as long as you're not running drag slicks and racing it at the track all the time.

 

Ford 9" is stronger, but it also requires more HP just to rotate the gears, so you need big HP to use one or need one... and you still spell it F O R D....
NOT in my Chevy!

I thought I had chosen an 'easy one'... 72 Nova 8.5" 3.08 Posi unit.. I had to cut the spring perches off (not easy).. grind the tubes down smooth... today I pulled the stock rear (This USED to be easy-ier 30 yrs ago!).. After 10-20 times getting up and down getting the 'right wrench/tool'.. removing the springs (I'm replacing the springs too), disconnecting the emergency brake cable in each drum brake, disconnecting the brake line, disconnecting the driveshaft, disconnecting the rear from the springs (and finding ONE big nut that was screwed up by a prior owner and wouldn't come off).. dragging the rear end out with one spring still attached, flipping the rear end over to try again to remove the nut, finally resorting to the torch to cut the U bolt, then turning around to find that the vent was missing in the rear axle and when I flipped it over, it drained about half the lube onto my 'virgin' concrete (no virgin any longer!).. spending an hour with oil dri, Simple Green, and then scrubbing with wisk/tide/clorox and a brush, before rinsing.. and then scrubbing the grease off my arms so I can have lunch and take a nap!~ as I said earlier.. NOTHING is easy when you're pushing 69.. so after my nap, I had to head out to pick up a friend's trailer so I can go retrieve another Nomad tomorrow morning... ... It ain't Easy.. but it Must be fun.. or I would quit doing it? right?

 

[emoji106]

Sent from my SM-G930P using Tapatalk

 

I'm in the process of installing a ford 8.8 Just finished putting in a pocket kit and thought it would be fun to narrow a rear end for more tire space. The 8.8 is perfect for my project. It can narrowed 3" ( 2 7/8 to be exact) and no shaft splining required. Just chop the drivers side to match the passenger side. Picked up a passenger axle for $60. 11 1/4 disk, rear way bar, 31 spline and parts are easy to come by. 3.73 gears should work well on interstate with 700r4 w/OD. Fun project if you like a little fab work. I'm making a jig for lining up the axle to weld back together and another for re-drilling axle for 4.75 pattern. Should have about $600 total when done.

 

How are you planning on using the car? A sponsor on here Quick Performance sells 10 or 12 bolt and 9" for a Trifive.
http://www.quickperformance.com/

The cheaper route is a F@rd 8.8 which you could probably have done at a local shop for under $1500 a lot less if you can do some of the work. Here are some links with info about the swap.

https://www.trifive.com/forums/showthread.php?t=40890

https://www.trifive.com/forums/showthread.php?t=21538

https://www.trifive.com/forums/showthread.php?t=151663

http://www.jalopyjournal.com/forum/threads/anyone-using-a-95-01-explorer-8-8-rear.93621/

:anim_25:

 

Three years ago I bought my first 57 Olds 9.3 with 3.42 gears at a Swap meet for $50, My next one I traded a free 8.8 Ford for it to a buddy. The 3rd one I bought a complete 62 Olds car for $300 and parted it out and scrapped rest zero cost. I bought my fourth at a swap meet $75 and 5th one a 62 Pontiac saftytrack at as swap for $150. I run the first one in my 56 with a reman locker from Fabcraft all new bearings and redrilled axles just under $1200 invested including new brakes. Not buying they are hard to find or all that expensive. I could recoup a lot of my cost if I was willing to sell the 12 Bolt Posi I replaced.

 

I think it really depends on what part of the country you're in. Near Denver, the only ones I could find were $300 just for the housing. I looked for two years before I decided to go with an 8.8 which took me one week to find. And still, the only one that's a bolt-in is the one from '57 in the Pontiac...it's pretty limited if you don't have the skillset to modify it yourself. I'd also like to know how expensive it is to put a set of discs on an Olds/Pontiac 9.3...I doubt it's cheap (and the OP stated he wanted discs at some point). On a 9" or an 8.8...it is very cheap to run Explorer discs...I have C5 discs on mine...brackets were about $100 from Kore3.

 

"Easy swap" is relative on yours & friends knowledge and capabilities.

It comes down to
1- How are you going to use your car?
2- How much of the work you & friends can do
3- How much money are you willing to spend
4- How quickly you want it done

Make some phone calls to see what is in your area. The 10 & 12 bolt as well as the 9" & 8.8 will all work and have kits for disc brakes. Stock rear is 60" wide so typically many go for a slightly smaller width 58.5 - 59.75" with stock leaf springs. To get a rear that just bolts in with no major work is possible but it will either take time to find one or money to purchase what you want.

You answer those questions and that will direct you in the path you need to go.

:anim_25:

 

Go ahead and bite the bullet and get you a QP 9" ford for your 55. With 400 hp by the time its over you will wish you had.3::congrats:

 

A no brainer. Cost, strength, availability, option choices, easy gear changes. A 9" wins, hands down.

 

I very briefly considered a Ford 9" with posi and disk brakes set up for my Chevy, but the least expensive I located were between $2200-$3000, and finally decided 'NO Not a Ford part in my chevy'!

I bought a 3.08 Posi 8.5" Chevy from a '72 Nova that was the correct length for the Trifive (~60"), required no change other than removing/replacing the spring perch with 2" width ones for TriFive. I paid $700 for it and did the mods myself in my driveway. Since then I've bought another Nova 8.5" rear (2.73:1 ratio non posi) for $75. These can be rebuilt with gears of your choice for $300-400. Chevy/GM still uses the 8.5 rears in their half ton trucks!~

PS. Novas/Apollos/Omegas/? from 72 thru 77? will have the stock 60" width needed for a nearly stock/warmed over TriFive and will have the 8.5" gear set! I think these are the best Value for one of our typical street driven, gently hopped up TriFives.

 

PS. Novas/Apollos/Omegas/? from 72 thru 77? will have the stock 60" width needed for a nearly stock/warmed over TriFive and will have the 8.5" gear set! I think these are the best Value for one of our typical street driven, gently hopped up TriFives.

Good info about the GM 8.5, 10 bolts here:https://www.trifive.com/forums/showthread.php?t=186326

 

I just bought a QP 9" with a Yukon Third Member with 370 Gears and Yukon Posi $2100 delivered to my door. It is all brand new and the craftsmanship on the housing is incredible.

Wayne

 

Is that price WITH disk brake package and Park brake??

 

Oh no! No brake kit of any kind.

31 Spline Axles that are a work of art, and the axle housings are 3" DOM tubing, New Big Ford Axle Housing ends. Workmanship is about as good as it gets.

I am going to use C6 Corvette Disc brakes.

Wayne

 

It has nothing to do with the rear end but I would get rid of that glass fuel filter. Those things are notorious for leaking and if a rock should hit it where it is mounted you will have a problem. I am not trying to be a smart azz but I just think those things are a hazard.

 

Notwithstanding that I redid my stock set up with nitro spiders, cross shafts and side gears, new gm clutches, cap strap kit, and Moser axles, and doubt I will have any trouble with that set up, if I was looking for something reasonable, it would be the 8.8 swap. Strength wise it’s like a 12 bolt but better in so far as you can get one with a posi and rear disc brakes for a couple of hundred dollars. Some set up time, axle tube shortening if needed, professional welding if you don’t have the equipment or know how (would be professional for me, lol, as I weld like I drywall, 40 pounds on and sand 39 off), axle shortning and redrilling if needed, I think you are likely to be all in for what, a thousand or less.

I guess for reasonable cost the next on the list would be the 70s 10 bolts, but truth be told, I would redo a stock set up before I would go to the aggrevation of doing that swap.

Yep, I agree, in terms of ease of swapping and aftermarket support, the 9 inch style rear is hard to beat but all in, I would not say the cost is all that reasonable. And yes, the offset nature does not appeal to me so I would want a real housing set up for a trifive. I agree that there is some parasitic loss with a 9 inch but this is not super stock or NHRA comp, al least not for me anyhow, and it’s not like a 9 inch is like having a donkey pulling in the opposite direction. So I think the 9 inch is a pretty good choice if the $$$$ allow that option.

 

I got a low mile 8.8" Ford rear out of a 2000 Explorer from a local junkyard. It had factory posi and 3.73 gears for $250. I opened it up - looked practically new inside from what I could see. It came with disk brakes, rear sway bar and the factory traction bars. I used all that stuff

I blasted it, painted it, welded on new spring perches (left the old ones on there) and bolted it up. I already had an explorer driveshaft from when I put the 5 speed in it. When I did the LS swap - the ls sits fwd of where the SBC was in there - and the drive shaft length was good.

So now I have a fairly strong rear with 3.73 gears and posi with disk brakes, rear sway bar and traction bars. Probably totaled around $400 for everything. I think I got that driveshaft for like $80.

 

You didn't need to re-center that 8.8 rear so the driveshaft doesn't hit the floor?

 

No I didn't - and the rear springs are lowered too. I've even had two adults and two kids in the back seat - but didnt really hit any big bumps yet either.

here's a pic of the ride height with no one in the car.

 

I scored a 3.42 open 57 Olds rear complete at a swap meet and ordered a new Fabcraft Posi . With new bearings redrilled axles and brakes I am in for about $1100 and would not trade it for any FOMOCO junk.