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9" open to limited slip?

Hello,

This is way, way down the line, but.... (this forum needs something)

I swapped some junk ch**y parts for a ford 9" to go in my 56. I can't go pick it up until the truck is drivable again (catch 22?). I don't know the exact year it came out of. It is supposed to be 3.50 gears (is that even offered in a ford?). I thought ford had a 3.73...but what do I know. :redface:

A guy dad works with (I have gotten a lot of parts from him :cooldude:), tried it under a later truck and it was too narrow. He swapped it out with a later (wider) 9" and put his 4.10 gears in the newer one.

Anyway, it is basically a bolt in because it is from an early F-100. They got wider about 72 (or so).

It is an open carrier. Is there an inexpensive way to change that to a limited slip (or whatever ford calls it)? I looked around the net (places like hotrodders) and could not find the information.


thanks,
Brian
 

BKW

Ford Parts Guru
Hello,

This is way, way down the line, but.... (this forum needs something)

I swapped some junk ch**y parts for a ford 9" to go in my 56. I can't go pick it up until the truck is drivable again (catch 22?). I don't know the exact year it came out of. It is supposed to be 3.50 gears (is that even offered in a ford?). I thought ford had a 3.73...but what do I know. :redface:

A guy dad works with (I have gotten a lot of parts from him :cooldude:), tried it under a later truck and it was too narrow. He swapped it out with a later (wider) 9" and put his 4.10 gears in the newer one.

Anyway, it is basically a bolt in because it is from an early F-100. They got wider about 72 (or so).

It is an open carrier. Is there an inexpensive way to change that to a limited slip (or whatever ford calls it)? I looked around the net (places like hotrodders) and could not find the information. thanks,Brian
The rear ends widened in 1973, and Ford used to sell a kit (B9AZ-4880-A) to convert to Limited Slip. Whether Ford sells the kit anymore, I dunno...but someone must. The 3.50-1 ratio~(C9OZ-4209-A) is correct.
 
What is involved in the installation of this "kit"? Is it something that I can do in my driveway with hand tools or does it need too be taken to a shop with special equipment?

I have never been inside a rear end housing.

I assume this is not a spool. I know there are what they call "lunch box lockers" for the 8.8 that can be put in at home fairly easily.
 

BKW

Ford Parts Guru
What is involved in the installation of this "kit"? Is it something that I can do in my driveway with hand tools or does it need too be taken to a shop with special equipment?

I have never been inside a rear end housing.

I assume this is not a spool. I know there are what they call "lunch box lockers" for the 8.8 that can be put in at home fairly easily.
This is a job for a professional, because the rear end has to come apart to install the LS kit, and the lash has to be re-set when it goes together. All the bearings should be replaced while the rear end is apart, as well as the parts needed to reset the lash. Want all the parts numbers? Let me know.
 

BKW

Ford Parts Guru
bkw, do you know if the kit is still available?

Not from Ford, because there haven't been 9 inch rear axles for years...Ford found something cheaper, but in no way as good: the 8.8.


The kit may be available aftermarket, but, sorry dunno.
 

bowtiehatr

Certified Ford Tech
well i am a ford tech so i may be able to track one down. im working on my fsb and havnt torn into the rear yet so i am looking for ls options.
 

BKW

Ford Parts Guru
Good luck, they have been obsolete for over 30 years. The last one I sold was prolly in the early 70's. The clutches (4945/4947) are still available. That's about it.
 
I installed a Power Trax Lock Rite in my 9" It is like a locker in that you can jack up one wheel and the other will pull it off the jacks. It sends power to the wheel with the least amount of traction,
It was around $275 from Jegs.
It was pretty easy to install as you don't have to mess with the gear set up at all. Just follow the directions and mark everything like they say.
It goes inside the differential and replaces the spider gears. Works great
clint
 
I need to go pick up the rear end. Things keep coming up and I can never get up there when the guy is home. :(


The powertrax has good reviews by the ranger and explorer guys on the explorer forum. I didn't know they made one for the 9". Powertrax is owned by richmond gear now.
 
As far as I know PowerTrax does not make a locker for the 9". I'm one of the few people who can't recommend them though; I had one in an '87 Chev :eek: 4x4 and I had nothing but problems, went through 7 units (got so good at changing them I could do it on the side of the road at night), eventually the locker totally destroyed the gear set by breaking teeth on both the pinion and the crown gear.... Sorry that's my vent :blah:

Back on topic, if you want a LS unit there are lots of options but you could certainly find one at a wrecker and rebuild it for a pretty reasonable price but if you're not comfortable setting up a rear end stick with an open diff.YelloThumbUp
 
My Power trax is the Lock Rite set up. Maybe it is different then the one you looked for but I do have one. Mine replaced the spider gears and kept the side gears so it fits either 28 or 31 spline axles.
I use my truck mainly for daily driver status but do abuse it with several burnouts a month at least. Always a nice solid 2 wheel burnout with the worry of burning up any clutches if one wheels drifts off the road.
Off road perfomance is great. I can put one wheel in the air and the other would pull me out. Not that my truck gets that far off road. That's what the Bronco is for.
Clint
 
I stand corrected; for some reason yesterday when I did my search I missed the application index on the PowerTrax website :redface: which clearly shows the 9" as being available.

Still doesn't affect my opinion of their product; but obviously I am one of the few unlucky ones.
 
I want to hear as many opinions of the owners (and abusers) as possible. If I get something...it will be quite a while. Money is tight around here.

I have rebuilt many, many automatic transmissions, but have never been inside a rear end. It might be an adventure.....
 
The one thing I like about the Lock Rite is as long as you followed their instructions and marked things like they say, it doesn't affect the set up of the gears.
Everybody cannot like the same thing that is for sure. Be a boring world.
I have heard of 4x4's using them in the front end and welding the backend. Some love them some don't but it seems like more like it.
I wonder if there is a difference between which brand truck they were installed in.
clint
 
Well, if you've been inside lots of automatics doing a rear end should be a breeze, there are a few things about them that are finicky (setting pinion shims...) but by and large they're not too bad.

I haven't had a 9" apart since school but as I recall they pretty straight forward to deal with. Here a link to a how to if you're interested 9" rebuild

I honestly think I'm one of the few who've had trouble with the LockRite product, I'd go the Detroit Locker route if I needed an automatic locker. If funds weren't an issue I'd consider an E-Locker too but personally I like the idea of not having to flip a switch when I need it. For my current project, after researching many different alternatives I believe I will go with Detroit TrueTracs in the front and rear because they will be easier to live with in a daily driver. I've found full lockers to be pretty obnoxious to drive regularly. If you're constantly out in the mud or trails they're fantastic but on dry pavement they're not as much fun as it says in the brochure :)

Just my $.02
 
This is not a 4X4. This is my 56 F-100. 272 Y-block V8, 3 speed on the column.

The 9" is basically bolt in and has slightly higher gear ratio (3.50). It should help slightly with highway driving. I just hate spinning one tire trying to take off uphill in loose gravel.

I was basically stuck on a cruise (car club) a few weeks ago. I had to back all the way down somone's long driveway and get a run at the hill.

Better tires would help, but I want both rear wheels to pull.

We will see what happens. I don't even have the rear end here yet. I have to go get it when I can catch the guy home.
 
That why I'm going to the TrueTracs which are not a locker they are a no clutch type limited slip unit, here's a link. I have never been a big fan of the clutch type LS units, they work but they do wear out and they are not tolerant of shock loads.

The TrueTracs are undoubtedly more $$$ than the LockRite unit but if you have time to save I think your $$$ would be better spent on something that suits your driving style more than the LockRite. Whether that means a clutch type LS unit or a TrueTrac style unit at the end of the day it's your $$$ and your decision.

BTW I've run clutch type LS units in all the rear wheel drive vehicles I've owned and had to rebuild them all from time to time, I've got nothing but good things to say about the Auburn product line as far as the clutch type units go, I just think the TrueTracs are a better product and better suited to my needs. You may be able to find a good clutch style unit at a wrecker for a reasonable price and put some new clutches and springs in it and be totally satisfied with what you get out of it YelloThumbUp
 

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