Ford 9" rearend, how complicated??

[LynnJr]

Originally Posted by UATahoe

Awesome! So this is what i need? Also, notice it has an electrical plug in on the end of it. Does the factory valve have that?

Doesnt seem like it should be too hard to do. Especially right now while the motor is out. It seems like lately though most guys are having trouble with their rear disc conversions. Really dont want those headaches. I do know right now though, the rear drums seem to catch and sort of lock up really easily in any type of aggressive braking. I am guessing switching to discs would help that along with the prop valve.

If you look closely at my terrible pictures you will see the plug on the factory valve.When you stomp on the brakes and the brake lights come on it is that plug/sending unit completing the path that turns on the lights.You need it on a street truck but don't on a race truck.
On your current set-up locking the rears p this is quite common.As you apply your brakes the suspension compresses in the front and the back of the truck lifts up.As press harder the front really noses down and the back comes up even more shifting all the momentum forward and taking weight off of the rear.You end up locking up your rear tires.
The valve helps balance out that problem but on a factory vehicle it is pre-set and not adjustable.As you modify or change things on your truck like bigger tires a drop kit or a camper your proportioning valve stays the same so your braking is not perfect.
Any time you do a swap there are little gremlins that pop up.
In a swap like this expect to drill a new hole or two for the valve.
Expect the brake lines running into it needing attention like re-bending or different size ends.
Expect to use some solderless connectors to hook your wire to the new one.
Expect to run a custom parking brake line meaning one end will be too long so you will likely need to cut it to fit and then clamp it.They usually come with all the parts necessary.
Expect to buy new U-bolts
Expect a new universal or two.
Expect you might need to use a couple shims to get the pinion angle right especially if your truck is lifted way up.
Usually these are quite easy to do especially since it is already sitting it a chevy.The little gremlins are more annoying than a big deal.

[UATahoe]

Yeah, the little things are what always get me. LOL. You mentioned the universal, just meaning i may need to try a few to find the right one? I guess i was thinking i would just use mine??

Current setup doesnt actually use U-bolts, has the U-straps so good call on that one. LOL. And the truck is at stock height. Not lifted or lowered.

[LynnJr]

I have a driveline shop in my town so doing these things is pretty much straight forward.If the driveline doesn't bolt right up I take the shaft and the yoke to the shop and they give me exactly what I need.
I hate going to parts houses with these kinds of issues as they usually don't have any idea at all about anything out here.

In your pictures the rear-end has "U" bolts on it.

[UATahoe]

Are yout talking about the leaf spring U-bolts? Or are you talking about where the driveshaft bolts up to the differential yoke?

The one in the picture looks just like mine which uses the straps. Couldnt really tell what this one used.

[LynnJr]

Leaf spring

[UATahoe]

Oh ok. Gotcha. I was just going to request those come with the rearend. LOL

[Rufton]

Originally Posted by UATahoe

I think the drum issue could be a faulty install. Just had all of the rear brakes reworked, pretty much new everything. Should have done it myslef. Oh well.

Why do some say you have to change out the master cylinder too? Seems to be a lot of conflicting info out there.

The master cyl bore may be be a slightly different size which affects pedal effort. Some people like hard pedal and some like light. If you wish to change pedal effort then choose different master cylinder bore; etc.

Disc reservoirs tend to be larger in effort to idiot proof them and to add a leak safety factor. In a properly designed system the non-maintained reservoir level should be above minimum level when pad rivets are grinding rotor and caliper piston stroking from new pad to worn pad position. Routine maintenance of fluid level will avoid dry reservoir issue.

Some drum master cylinders come w/ residual pressure valve (coil spring and rubber valve located in port) to hold some pressure to wheel cylinder. Helps keep wheel cyl piston expanded to prevent seepage. In rebuild units I've got this residual pressure valving was long gone. Not difficult to remove. If not removed the discs won't float properly. Can test by spinning wheel by hand when car jacked up after pressing brakes.

[UATahoe]

Thanks for the info! It all tends to get a little overwhelming to where i feel like just sticking with the disc/drum setup. LOL. I am definitely short on experience when it comes to brake work.

[LynnJr]

Put it in and test it out.You can make changes as needed to avoid buying things you don't need.
Also call Willwood before doing anything and tell them your plan.They have worked thousands of people through this process.

[wraprail]

Originally Posted by LynnJr

If you look closely at my terrible pictures you will see the plug on the factory valve.When you stomp on the brakes and the brake lights come on it is that plug/sending unit completing the path that turns on the lights.You need it on a street truck but don't on a race truck..

The "plug/sending unit" in the picture is for the brake warning light in the dash. It will sense different pressure between the front and rear systems, moving the internal pistion and activate the warning light.
It has nothing to do with the brake lights.

To the OP,
I just installed a wilwood adjustable combo valve, same one you pictured on my 85 C10 with ford 9 inch and rear disc brakes.
I installed mine in the factory location on the front crossmember.
The bolt holes line up perfectly. I had to add a spacer under both bolts and use longer bolts. ( i used several 1/4 flat washers stacked to roughly 1/2 inch thick)
I did not use the brake switch in the wilwood valve and left the stock switch on the brake pedal. Just leave the wilwood switch disconnected.
You will need to run new 1/16 steel hard line to the rear brakes from the wilwood valve as well as new 1/16 hard line from your master to your wilwood valve.
You can buy these at any auto parts pre cut and flared with 3/8-24 fitting installed. You can bend these lines by hand without any special benders. Just take your time. Its easy. I bent every line on my truck by hand using items like a welding cylinder and large sockets it aid.
As for master, try a corvette master. I use one for many years. Now i'm using a Dodge Daytona (early 90s) 1" bore but i"m using manual brakes.
You will need adapters for hard line connections. Any auto parts has these.
Ford uses U bolts not straps. Auto parts also carry these
Sounds like a great deal. Go for it!
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[LynnJr]

Yep I saw that but unfortunately I can't edit my posts on this site.

[UATahoe]

Thanks for all of the info. Definitely going to go for it. I will just adjust as I go to make it happen. I think I can get it done. Especially with all of the great help from here.
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[jitteryguy]

once you get it all install'd and adjust'd you'll love the 9". I put one in my MonteCarlo with disc and used the same WilWood valve, well worth the time and money.

[LONGHAIR]

Originally Posted by LynnJr

Sorry about that.
Alot of people think there is something special about posi-traction and there isn't.It is simply limited slip and as time goes by it gets looser and looser.
Does the 9 inch have a detroit locker? A Detroit Locker works like Posi or Limited Slip.
In short none of the various names given to rear-ends means much.You either have.
One wheel spinning.
Sometimes two wheels spinning.
Both wheels locked and always spinning.
All the rest is marketing.

That is absolutely not true. A Detroit Locker is very different from a clutch type unit. Very!
They clutch type units work just like an open differential as far as allowing the wheels to turn at different speeds. They just have pressure applied to them which makes the differential action stiffer....thus the term "limited slip". The "slip" is the differential action, like an open rear end.
Yes, the clutches do wear over time, allowing for less pressure, but it takes a lot of time, use, abuse. Most of the models out there are rebuildable anyway, if you would ever need it.

Posi-traction is just Chevrolet's trademarked name for a clutch type "limited slip differential" (lsd) Ford calls theirs Traction-loc. Pontiac= Safe-T-trac, Chrysler= Sure-grip, Dana= Trak-loc......etc.

Posi just became the generic term.

Detroit lockers are a completely locking unit. They do not slip. Their differential action works by un-locking one side from the other. This is a noticeable action, some applications more than others. They drive differently on the street and not for everyone.

[LynnJr]

Longhair
If you put a tire in the air on a detroit locker the springs push against the outside gear and unlock the rear-end making it a one legger.Your supposed to be able to hit the throttle and have the free wheel get instant traction.I have never been able to see this happen with a Detroit Locker.

If your driving down a very curvy road the inside wheel has the power to it as the outside wheel with its greater speed has unlocked the outside gear due to its camming against the teeth and your back to a one legger again.

A detroit locker has clutches as well.

This is how I was referencing the similarities.

If you want both wheels spinning all the time you either use a spool or a Air-Locker as all the others will become open differentials when you least want it.This was my point in the post you quoted.

[KQQL IT]

No clutch in my locker.
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[LynnJr]

Detroit Locker - YouTube

For those without flashplayer
http://www.stangtv.com/news/eaton-vi...rential-works/

[LONGHAIR]

There is no clutch action to a Detroit locker...period. You example of one wheel on the air is not true either, as long as it was locked when the one wheel lifted it will stay locked.They don't unlock as easily as you make it sound. It's the slower wheel that unlocks, but it only does so if the drivetrain is "unloaded". (Coasting/off-throttle) That is why I have always said that they are more unpredictable with a manual transmission. They have a tendency to "push" or "plow"straight when turning, like a spool. The tricky part is if you allow it to unlock in this condition, you go instantly from understeer to oversteer. It takes some getting used to and is just not for everyone.
I am not a huge advocate of lockers on the street, but they are very different from a clutch unit....no clutch action ever.

[68Timber]

Originally Posted by LONGHAIR

There is no clutch action to a Detroit locker...period. You example of one wheel on the air is not true either, as long as it was locked when the one wheel lifted it will stay locked.They don't unlock as easily as you make it sound. It's the slower wheel that unlocks, but it only does so if the drivetrain is "unloaded". (Coasting/off-throttle) That is why I have always said that they are more unpredictable with a manual transmission. They have a tendency to "push" or "plow"straight when turning, like a spool. The tricky part is if you allow it to unlock in this condition, you go instantly from understeer to oversteer. It takes some getting used to and is just not for everyone.
I am not a huge advocate of lockers on the street, but they are very different from a clutch unit....no clutch action ever.

^What he said.

[LynnJr]

Longhair
I wish I had you set up my Detroit Locker.
Mine would not lock up both wheels when one wheel was in the air.
I have no idea if it was locked or unlocked when the wheel went into the air.
This is my own real world experience not what the brochures that come in the box say should happen or what the guy selling it at a shop tells his potential customer..
I belong to a 4X4 club and some of the guys do like them.I sold mine after it performed as described above and went with the Air-Locker.I don't know if you've set up any air lockers but in my experience they are a far far superior set up.I base all my opinions on what I have personally seen,driven or experienced not what I see posted on the internet.

There is no clutch action to a Detroit locker...period.

I guess I am not phrasing it correctly but the locker I had would switch back and forth from wheel to wheel.You could hear it and you could feel it.It might not have been a clutch action but in the posted videos above you can see the clutch assembly being pushed away from the spider gear and that is when it would clunk and switch sides.

[KQQL IT]

Dog clutch maybe.
I have a used NASCAR locker and it has no dampner like some have. Its so loud that people think there is something broken.
Put lubrication engineers 140 in it and its still loud.
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[LynnJr]

Dog clutch maybe.

In the video Eaton labels it a clutch assembly.I have no idea why Eaton would do that.

[LONGHAIR]

Yeah, I don't know why they would call it that either? Makes no sense to me.
The actual clutch type units look much like a miniature version of automatic transmission clutches and steels and they progressively slip depending upon how much pressure is on them.
Lynnjr, I really feel for you. It sucks when you have something like this and it just will not perform as expected. It seems like the clunking you heard/felt is normal. Mine was the same way and it worked flawlessly for me. This was in a 454 sm465 with 40" tires.
Most of the guys I have ever heard complain about them were driving manuals , but I never had problems with mine. Automatics seem to keep more load against the drive teeth, so they don't act as harsh.

[LynnJr]

Longhair
My truck is a 1990 5 speed just my luck.
All my buddies own old mustangs with 427 sideoilers and 428 Cobra Jets so the clunking was expected.
My biggest problem was the truck would have two tires touching earth and I couldn't move forward or reverse.
With the Air Locker you still get 2 tires off the ground and still get stuck but all 4 wheels are moving.

[UATahoe]

Originally Posted by wraprail

The "plug/sending unit" in the picture is for the brake warning light in the dash. It will sense different pressure between the front and rear systems, moving the internal pistion and activate the warning light.
It has nothing to do with the brake lights.

To the OP,
I just installed a wilwood adjustable combo valve, same one you pictured on my 85 C10 with ford 9 inch and rear disc brakes.
I installed mine in the factory location on the front crossmember.
The bolt holes line up perfectly. I had to add a spacer under both bolts and use longer bolts. ( i used several 1/4 flat washers stacked to roughly 1/2 inch thick)
I did not use the brake switch in the wilwood valve and left the stock switch on the brake pedal. Just leave the wilwood switch disconnected.
You will need to run new 1/16 steel hard line to the rear brakes from the wilwood valve as well as new 1/16 hard line from your master to your wilwood valve.
You can buy these at any auto parts pre cut and flared with 3/8-24 fitting installed. You can bend these lines by hand without any special benders. Just take your time. Its easy. I bent every line on my truck by hand using items like a welding cylinder and large sockets it aid.
As for master, try a corvette master. I use one for many years. Now i'm using a Dodge Daytona (early 90s) 1" bore but i"m using manual brakes.
You will need adapters for hard line connections. Any auto parts has these.
Ford uses U bolts not straps. Auto parts also carry these
Sounds like a great deal. Go for it!
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Can i not just install the prop valve and retain the original brake lines? Just cuious why i would need new lines to the rear.