Hello,

I am looking to put a real strong rear end under my truck. (1950 Chevy).
I want to tow stuff and blow import racers off the line at stop lights. I am looking for some recommendations. Please tell me whats worth looking at, and what not to bother with. I will rebuild any rear end, but need to make this cheap, so no custom jobs please. A

Here are my specs.
55 1/4" backing plate to backing plate
71 1/2" tire to tire
Limited slip or Posi
6 Lug Chevy Bolt Pattern.

Its going in a 1950 Chevy Truck with.....
283 rebuilt w/ 650CFM Edelbrock or a Buick 455 w/ Supercharger
Borg Warner -t10 or t65 trans.


I could really use someone's help. All of my hotrodder friends know nothing about rear ends, so I hope you have some experts. I have been in the local junk yards, but need a clue what is quality and what is junk.

Thanks
johnryan

johnryan@myrealbox.com

Ford 9" would be my first thought, but clutch type posis for 9s arnt as good from what I hear because of limited diameter of the clutch plates. I've never had a 9 with a posi, so... Theres so much aftermarket crap for 9s...

You could use a GM 12/10 bolt with an Eaton Posi, possibly crmo shafts to beef it up a bit. The Eaton/crmo combo will make it stronger than stock. The 89 plus (I think) 10 bolts had 30 spline axleshafts, earlier had 28s. If you get new carrier/shafts, you can use an older housing, just order the 30 spline stuff. 12s had 30 splines.

Or a 14 bolt semi floater w/ 6 lug shafts and the Eaton, its heavier duty, but will weigh more. It has a 9.5" ring gear and 33 spline shafts

Or a SF Dana 60. Most, if not all, were 35 spline shafts. Probably about as heavy as the 14 bsf.

Hello,

I am looking to put a real strong rear end under my truck. (1950 Chevy).
I want to tow stuff and blow import racers off the line at stop lights. I am looking for some recommendations. Please tell me whats worth looking at, and what not to bother with. I will rebuild any rear end, but need to make this cheap, so no custom jobs please. A

Here are my specs.
55 1/4" backing plate to backing plate
71 1/2" tire to tire
Limited slip or Posi
6 Lug Chevy Bolt Pattern.

Its going in a 1950 Chevy Truck with.....
283 rebuilt w/ 650CFM Edelbrock or a Buick 455 w/ Supercharger
Borg Warner -t10 or t65 trans.


I could really use someone's help. All of my hotrodder friends know nothing about rear ends, so I hope you have some experts. I have been in the local junk yards, but need a clue what is quality and what is junk.

Thanks
johnryan

johnryan@myrealbox.com


Take a look at Tacoma or Tundra rearends. Probably do fine for your needs. 6 lug, 60 or 65 inches wide, not too heavy, but strong enough for v8 power.

Or a 14 bolt semi floater w/ 6 lug shafts and the Eaton, its heavier duty, but will weigh more. It has a 9.5" ring gear and 33 spline shafts

The 88-98 C2500 (2wd) version is the narrowest... about 63-64" across the wheel mounting surfaces. Usually have 3.42 or 3.73 gears

Nissan H223B is another 6-lug I thought I should mention... AFAIK, they have 4.xx gears.

i would look for a 14 bolt semi-floating rear end with 6 lug wheel pattern. it has a big r&p, big shafts, and you can look to the aftermarket for a posi, or find one with a posi already there and easily find clutchpacks to rebuild them tight. they come mainly with lower gears, which is what you want red light to red light or to tow. (and if your not doing a disk conversion, at least you will have some big drums to stop with).

do you already have expensive rims? your other option would be to run a eight lug wheel on the rear and then your options are much more plentiful. you could go to the junk yard and trip over rear dana 60's ,70's - corperate 14 bolts - eaton -AAM - sterling, ect, ect. all capable of handling a blown big block, with an aftermaket for gears, lockers, limited slips, shafts,disk conversions, ect.


im gonna start a stink here, but i sure as hell would not run a toyota or nissan or a 10 bolt chevy with a blown 455 rocket.

-humper

im gonna start a stink here, but i sure as hell would not run a toyota or nissan or a 10 bolt chevy with a blown 455 rocket.

-humper

No dissent here, I've blown two 10 bolts with a TBI 350...on pavement. Frankly, I don't know anything about Nissan axles but a 'yota axle isn't strong enough to handle a blown 8 and a heavy foot. I think a 14bsf would be your best choice. Go to a yard that knows what they're doing and they'll lead you to a ton of them. I THINK most of them came with 3.42's and 3.73's (that's all I've ever found) but I'm sure there are some 4.10 units out there.

Well, he said it might be a 283, If thats the case you could save some weight with a 10 or 12 bolt rear and be fine, especially with an Eaton posi, which is a much stronger carrier than stock and crmo shafts.

I would get a SF D60 or 14bsf with a blown BB as well. I actually have a blown 496 in my k20, but its a 3/4 ton, so it came with a 14bff :) It kinda depends how much you use that power, I rarely open the secondaries on that motor, its huge overkill, and you should have hearing protection at WOT... But it is fun.

I have a 14sf on my Burb, the older ones use obsolete axleshafts, the only one I could find anywhere, including junkyards, was from west coast diffs. When I got the axle ($50) it had no brakes, and same story as the shafts with the older 14bsf drum brakes. They dont exist. I did a disk brake conversion just because it was going to cost HUGE $$$ to buy new drum brake parts. The disk conversion went well, so I'm happy overall, despite the obstacles. I'd try and get a newer 14sf, some of them have disks stock as well, not sure of the years, but I think theyre late 90s and on.

My .02's, I putting together a 2x4 '73 Blazer with a 14 ff soon to be a ford 9" because there is alot of combinations out there.(detroit locker) I'll be running a BBB 462
and a s//p t-400.
Dan

Hey Everybody,
I really appreciate your help. I was at the local yard yesterday think i know what i am gonna do. I have 6 lug wheels now, but I will start looking for 8 lugs and put a 14 bolt in it. I am going to start with the 283 engine because it is what is built right now. I am on the trail of a big block though.

Everyone here is great. I appreciate it.

John.


I will forward pics to this as reference for others in my spot.

Wait timeout, there are plenty of 6 lug 14bsf if that's what you're referring to. I swapped one into my daily driver a month ago. If you're talking about a full floater then disregard this.

Go with a semi-float Dana 60 in 35 spline. They can be found in 6-lug under some late 60's maybe early 70's GM trucks.

Yeah, dont go 8 lug for a hotrod. Its much heavier than you need. I'd agree a SF D60 or newer 14bsf is a good combo of stregnth without going overboard. You really dont need a ff 8 lug axle unless you want to tow heavy stuff with it regularly. I'd also seriously consider a disk brake setup as drums are a lot heavier, and theyre rotating mass, a lot of which is further out from the center of the hub than disks, which costs you HP.

In your particular case I wouldn't tell you which way to go for sure, but I can tell you that in hot rodding circles the 9 inch Ford is THE axle of choice for 90% of all serious buildups. They are strong in stock form and can be made nearly indestructible (for street/strip use) with the right parts, they have a HUGE aftermarket following, they are light (especially for their strength), and they have a removable center section for easy gear changes and workbench gear set-up. A stock 9" would laugh at your 283 and could certainly be built strong enough to handle a big blown Buford on street duty.

A Dana 60 SF would also be an excellent and very strong alternative but they are a little heavier. Great in a truck though. Maybe the perfect axle for your needs.

The SF 14 Bolt would be worth thinking about too, but I really don't know how many parts are available. I haven't ever had one and don't know a whole lot about 'em aside from the basics.

A 12 Bolt rear would probably work but it's the weakest I'd use. Just so you know, the car versions have a bigger pinion dia. than the truck versions do, believe it or not, but they only come in a 5 lug bolt pattern. In any case, you'd have to build it up to live behind a blown 455.

A 283 would be fine but a blown 455 would eat a 10 bolt alive if you used the throttle in any sort of unreasonable fashion. The crmo shafts and Eaton case would certainly help but still...

Just my opinion, but a FF 14 Bolt would really be overkill in your case (assuming pure street duty) unless you are gonna put a dump box on your truck and haul gravel! Plus they are big and HEAVY, they only come in 8 lug BP, and as mountain4x4 said, getting all of that weight spinning really eats power and slows driveline acceleration in the stoplight drags.

If it were me, it would be between the 9", the D60, and the SF 14 Bolt (if you can get the parts you want for it). Just my $.02.

Sorry about that, totally omitted the 9". I hardly know anything about the internals since I've never screwed with one, but the aftermarket support for them on the rodding scene is absolutely unparalleled. It appears to be the Warn 8274 of rear axles. Look through a Jeg's or Summit catalog once and you'll see what he means. Also, the 9 is easily upgradable if you want to run the little motor now and a blown beast later.

I would think a 14bsf would be easier to find, but like I said, my knowledge of the 9 is extremely limited and I think both would be excellent choices.

The problem with the 14SF is that the axles have a huge amount of taper to them. That will make them very hard to narrow and you would be best off just buying new axles of the proper length.

Because of the "I want to tow stuff" was why I would recomend the D60 over the 9". I don't think the bearings in the 9" could hold up to the load that the 60 could.

The 9" doesn't have 6-lug axles going for it... so once you start changing stuff... where do you stop?

The ~63" 14SF I mentioned above can be further 'narrowed' with some large (5") backspacing wheels... like the OE ones on 88-up 1/2-ton 4x4s.

The rare D60SF used in the 60's & early 70's GM products has D44 shafts... 30-spline and small tubes. AFAIK the 35-spline D60SFs are all 8-lug.

Didn't realize the 9" didn't come with 6 lug BP. I knew they came in quite a few of the lighter trucks (old Broncos etc...) but I guess they're all 5 lug?

I just have to say, everyone here rocks

I really appreciate everyone's help. It has been a challenge finding a narrow rear end for my truck w/ 6 lugs.

I got one today. its a 10 bolt out of a 56 chevy. 6 lug. The primary reason for this swap is bc the open drive line. My truck has this stupid torque tube thing. It sux. not anymore. I am gonna start with this and my 283. This is enough to learn on. The junk yards around tampa didnt have any 14 bolt semi floating, but that is what i think i am gonna get. I will pass all of this info along to friends in my circles.

Lastly, Every other hotrodder converts to 5 lugs, and I wanted to keep mine because i have nice old school wheels. Otherwise I would do a ford 9".

Again, everyone here rocks. Thanks.
I will be happy to entertain questions on paint, restoration of any parts or rust.