Advice or tips for my 9" upgrade

[roddster]

  Just read the Torson information and the 2 user posts, so, I'll put that as a maybe.  On my former 66 with the Detroit locker, it was kind of unsettling in a corner.  Seemed like somebody was pushing and releasing thier push while you are going around a corner.  Didn't like it.
  So, on to the gear ratio choice.  There will be some drag strip runs, and track days, but mostly just cruising.

[Shawn]

     Summit sells the Yukon type center section.  It has the rebuildable plates for the equal lock.
  OK, suggestions welcome

Understand Yukon product is made in India.  It is a fair value for the price.  But I wouldn't put their stuff in my vehicle if you gave it to me.  My firm does business with Mark Williams Enterprises.  In my experience it is the best engineered and manufactured Ford 9" vendor.  Voice of experience, a Detroit Locker can be dicey on slippery pavement.  Good reference in Carroll Smith's book, Engineer To Win.

I purchased and installed a Yukon locking rear and new ring pinion for Ford 9".  This was set up with all new bearings etc.  It was very very noisy we removed and rebuilt again with the same products = same results.  The job was performed by a professional and I will never buy Yukon again.  Cost savings were not worth it

[gt350hr]

  3.50 is a good ratio but there have been some noise issues lately even on genuine Ford gears.
I was factory trained to do Ford diffs in '68 and still can't get some gears to be quiet. Be careful on what you buy.

[mikeh]

+3 on Detroit Truetrac. Quiet & works great behind ~ 550 HP & 5 speed, w/ no maintenance.

[pbf777]

     Note that any of the friction worm gear gear types (as often I refer to as: "Bind-O-Matics"     ) such as True-Trac and Torsens, offer differential function by being defeated, which is fine for street driven and even hard track driven vehicles, but not unlike friction-plate types, when the power applications get high enough, the traction becomes questionable particularly left to right, the units become unreliable for proper expected function.  They also do have a seldom discussed wear-in-to-disfunction behavior which if used hard will require periodic maintenance to recover from.   

     This behavior I'm referring to is that in time, and with use, the worm wheels to worm gears become polished, this reducing the friction function and the intended resistance to the single wheel drive result (one-wheel-peel!   ) until in time the unit provides a greatly reduced "posi-traction" value.  Next, we have experienced the effect of when spinning one wheel, say coming out of a turn under hard acceleration the worm wheels are spinning at a high rate within the carrier housing that they are captured, heating up, until apparently with growth seize and lock, this immediately stops the spinning wheel and snatches the driving wheel free, this transfers the driving torque often in opposite of the previous experience leading up to this event and causing the vehicle to abruptly change direction!  YIKES!     

      In our experience the "fix" is to periodically remove the worm wheels and gears and abrasive blast them to ruffing-up the surface texture, and all will be good again!       

      Be aware that these units are not indestructible, that banner although worn by no one, does hang closest to the Detroit Locker.         

      And:   

Understand Yukon product is made in India.   ......... I wouldn't put their stuff in my vehicle if you gave it to me. 

      Scott.   

[gt350hr]

    FEW (if any) of us use these cars as daily drivers so 10-12,000 mile a year in use just doesn't happen like it used to when they were daily drivers so "longevity" isn't usually an issue unless your car is a dedicated "race car" ( road or drag) where breakage happens more frequently. Because we differ in driving styles and uses , you see a wide variety of opinions and preferences. The smoothest and most positive design I ever drove was the Weisman "sprag style'. These units had a unique locking method but it's $1,500 (1969 cost) price tag was out of the reach of most racers back then. The Ford T/A teams had a couple each , but not every driver liked them. The good old fashion Detroit Locker was still king back then.

[Royce Peterson]

I put the Detroit Locker in my GT-E in 1994 when I restored it. Since then I have been a regular at nostalgia drag racing events with hundreds of passes on the strip. I have also put more than 30K street miles on the car. The engine has been rebuilt twice since then. The transmission once.

When does this breakage occur? Am I about to have trouble? Why are you the first person to say this?

Last time I drove the car was about three weeks ago. As usual I let it warm up as I drive, then after it is warmed up I drive it like I stole it.

  There are also "special" Nascar "left turn" lockers made for easier disengagement on a left turn. Those should be avoided too. An H case locker "works " fine , BUT you must change to the 3.250 bearing , aftermarket , case.  The noise and harshness of an H case locker can be changed by the use of lighter tension springs in a street application. The MAJOR benefit of the H style locker is the "hubs" where the bearings ride are FAR stronger eliminating breakage of the ring gear side hub and or spinning the bearing on that side. This IS and has been a problem with B ( normal) case lockers and earlier "small bearing" units . I've had 30 or more ruined that way. Ford "used" to sell an empty 31 spline locker case and I saved most of them that way.
  Randy

[shelbydoug]

I HAD a detroit locker in my car for a couple of weeks in the early '80s. So that would probably tell you about the model it was. I don't remember.

It was brutal on locking and unlocking especially on tight left hand parking lot type turns. I went as far as to buy a "Ford Motorsport" spring for it. That never got installed and is still in the box in my shop.

I couldn't stand the thing and put back the traction lock.


Now, to what you two guys are grumbling at each other about. Does the case on both the locker and traction lock break? Not on mine BUT in that era, 70-late 80s, there WAS discussion about that and yes I do remember FORD servicing the case halves for a short BRIEF time.

Now if the locker has been civilized some time after the '80s, "power to the people!" Great BUT in my experience the thing was just plain "an uncivilized animal". Opinion? Sure. Just mine from my brief experiences with the locker.


Now. NASCAR. I guess time marches on? In my day, NASCAR ran OPEN 9" rears. THE discussion from THAT ERA, was the reason being, IF the car broke an axle, the car would spin out with a Detroit Locker.


Now Royce. I'm a little older then Randy is and not nearly as experienced. What we both have in common TO AN EXTENT is that we were both "punk kids" and in my case, the "old timers" did not easily share information and in some cases were just plain violent, so what I know from them, that was gained by accident mostly.

Randy had a different technique but it might also be attributed to him being an LA kid and me a NY'er that even the 'Jersey Guys disliked and forget about the Holman Moody Charlotte NC guys. To them the Civil War was still on (and still is).


I personally have not broken a traction lock case, certainly couldn't after two weeks with a detroit locker, and being strickly in a 'bad ass Chevy' area, had to be careful what neighborhood I was going to and disguise myself appropriately if need be and had no other "Ford" guys to talk to, just me, all by my lonesome?

"Your mileage may vary?"

[Royce Peterson]

The Detroit Locker was totally revised in the mid 1970's. Sounds like you had one of the early DL's like Shelby and Ford used on production vehicles. The one I have doesn't do that, nor did any of the many other Detroit Lockers I have installed before or since.

I did drive a '65 Mustang years ago that had the entire driveline from a wrecked '70 Boss 302. That one had a 4.30 DL in the rear end. A very rowdy Boss 2 under the hood with headers, cam and a big 750 DP. It made a wonderful chunka - chunka - chunka noise going around corners and then you could feel when it locked up going straight. Totally different from anything except an H Locker. I don't dislike those but they are a different thing entirely.

I HAD a detroit locker in my car for a couple of weeks in the early '80s. So that would probably tell you about the model it was. I don't remember.

It was brutal on locking and unlocking especially on tight left hand parking lot type turns. I went as far as to buy a "Ford Motorsport" spring for it. That never got installed and is still in the box in my shop.

I couldn't stand the thing and put back the traction lock.


Now, to what you two guys are grumbling at each other about. Does the case on both the locker and traction lock break? Not on mine BUT in that era, 70-late 80s, there WAS discussion about that and yes I do remember FORD servicing the case halves for a short BRIEF time.

Now if the locker has been civilized some time after the '80s, "power to the people!" Great BUT in my experience the thing was just plain "an uncivilized animal". Opinion? Sure. Just mine from my brief experiences with the locker.


Now. NASCAR. I guess time marches on? In my day, NASCAR ran OPEN 9" rears. THE discussion from THAT ERA, was the reason being, IF the car broke an axle, the car would spin out with a Detroit Locker.


Now Royce. I'm a little older then Randy is and not nearly as experienced. What we both have in common TO AN EXTENT is that we were both "punk kids" and in my case, the "old timers" did not easily share information and in some cases were just plain violent, so what I know from them, that was gained by accident mostly.

Randy had a different technique but it might also be attributed to him being an LA kid and me a NY'er that even the 'Jersey Guys disliked and forget about the Holman Moody Charlotte NC guys. To them the Civil War was still on (and still is).


I personally have not broken a traction lock case, certainly couldn't after two weeks with a detroit locker, and being strickly in a 'bad ass Chevy' area, had to be careful what neighborhood I was going to and disguise myself appropriately if need be and had no other "Ford" guys to talk to, just me, all by my lonesome?

"Your mileage may vary?"

[roddster]

  OK, ENOUGH ABOUT the Detroit Lockers. Take it to another thread!

   Now, any other additional advice?  ratios, bearings etc?

[gt350hr]

   The FIRST weak link in any 9" is the crush sleeve or "pinion bearing preload spacer". The "crush sleeve" used by many manufacturers , is a good "automotive production" way of setting diffs up. If a solid , select fit "aftermarket" spacer is used there , "most of you" will not have a problem with even a "standard duty" case. This spacer IS standard issue on Nodular iron cases with "Daytona " pinion retainers. Bearings should be restricted to USA , Mexico or Japan manufacturers. AVOID those made in China. "Production" Ford hardware is super durable and I see no reason to change.
   Serious drag racing or road race ( endurance) is a bit different and if you are doing that , PM me and I'll help.
   Randy

[gt350hr]

   Royce,
      My drag race experience goes back to the '65-66 A/FX Mustangs that had them stock and ran hard wall slicks wit toploaders. The ring gear side hub broke often. the mainly occurs with manual trans cars where the HP is High and the tires are wide. The internal "slack" is not preloaded like an automatic equipped car is. A ten second 4spd car is NOT a good place for a locker. An 8 second automatic ( without a trans brake) is fine simply because the "foot braking" eliminates the internal slack. The highest load is placed on the ring gear side bearing hub as the ring gear tries to wedge away from the pinion gear without sufficient bearing preload or a machined steel "spanner" ,  deflection can cause a failure over time. It also led to "spun bearings on that side. "Most" of the broken units I have fixed were from 4 speed cars including ''road race units" with higher mileage potential and far more "cycling''. This is why Nascar teams "mile" them out before they become a problem
Since you don't "campaign" your car on a weekly basis , the use/abuse is far less than some one  that put a thousand or more passes a year on one like I do. Application and use is very important when choosing parts. Heck I ran ( and literally SAT on) a 31 spline traction lock unit in my 7 second 177 mph front engine Cleveland powered dragster. 50+ runs and never broke a "stock" side cover. I set the clutches up with zero preload is the reason.
   I have used a Detroit locker  since '66 and they are GREAT in the right application. You are one that is using it in a "happy" situation.
    Randy

[Royce Peterson]

Note that Ford didn't use a crush sleeve in the 31 spline applications like the Cougar GT-E or the Shelby Mustangs. 428CJ Mustang / Cougar / Comet / Fairlane, Boss 302 Mustang / Cougar, Boss 429 Mustang / Cougar, Boss 351 Mustang, 429 CJ / SCJ Mustang / Cougar / Comet / Fairlane etc. In those applications it is a solid steel spacer that does not get replaced every time.

   The FIRST weak link in any 9" is the crush sleeve or "pinion bearing preload spacer". The "crush sleeve" used by many manufacturers , is a good "automotive production" way of setting diffs up. If a solid , select fit "aftermarket" spacer is used there , "most of you" will not have a problem with even a "standard duty" case. This spacer IS standard issue on Nodular iron cases with "Daytona " pinion retainers. Bearings should be restricted to USA , Mexico or Japan manufacturers. AVOID those made in China. "Production" Ford hardware is super durable and I see no reason to change.
   Serious drag racing or road race ( endurance) is a bit different and if you are doing that , PM me and I'll help.
   Randy

[shelbydoug]

The Detroit Locker was totally revised in the mid 1970's. Sounds like you had one of the early DL's like Shelby and Ford used on production vehicles. The one I have doesn't do that, nor did any of the many other Detroit Lockers I have installed before or since.

I did drive a '65 Mustang years ago that had the entire driveline from a wrecked '70 Boss 302. That one had a 4.30 DL in the rear end. A very rowdy Boss 2 under the hood with headers, cam and a big 750 DP. It made a wonderful chunka - chunka - chunka noise going around corners and then you could feel when it locked up going straight. Totally different from anything except an H Locker. I don't dislike those but they are a different thing entirely.

I HAD a detroit locker in my car for a couple of weeks in the early '80s. So that would probably tell you about the model it was. I don't remember.

It was brutal on locking and unlocking especially on tight left hand parking lot type turns. I went as far as to buy a "Ford Motorsport" spring for it. That never got installed and is still in the box in my shop.

I couldn't stand the thing and put back the traction lock.


Now, to what you two guys are grumbling at each other about. Does the case on both the locker and traction lock break? Not on mine BUT in that era, 70-late 80s, there WAS discussion about that and yes I do remember FORD servicing the case halves for a short BRIEF time.

Now if the locker has been civilized some time after the '80s, "power to the people!" Great BUT in my experience the thing was just plain "an uncivilized animal". Opinion? Sure. Just mine from my brief experiences with the locker.


Now. NASCAR. I guess time marches on? In my day, NASCAR ran OPEN 9" rears. THE discussion from THAT ERA, was the reason being, IF the car broke an axle, the car would spin out with a Detroit Locker.


Now Royce. I'm a little older then Randy is and not nearly as experienced. What we both have in common TO AN EXTENT is that we were both "punk kids" and in my case, the "old timers" did not easily share information and in some cases were just plain violent, so what I know from them, that was gained by accident mostly.

Randy had a different technique but it might also be attributed to him being an LA kid and me a NY'er that even the 'Jersey Guys disliked and forget about the Holman Moody Charlotte NC guys. To them the Civil War was still on (and still is).


I personally have not broken a traction lock case, certainly couldn't after two weeks with a detroit locker, and being strickly in a 'bad ass Chevy' area, had to be careful what neighborhood I was going to and disguise myself appropriately if need be and had no other "Ford" guys to talk to, just me, all by my lonesome?

"Your mileage may vary?"

This was about 1982. The locker came from Bill Maier racing.

Not only would it spin the left tire on a tight left hand turn, it would wiggle the car at speed like I had bias tires and was catching the joints in the road.


The Traction Lock actually has more of a reputation of breaking the case then the locker does. I think that might be more of an issue with a big block?

[roddster]

  I subscribe to these magazines: Hot Rod, and Hemmings Muscle car.  In the September issue of HMC there is an article about a quiet 9" Ford rear end.  Check it all out at www.johnsindustries.com
  Online choices for options such as read housing, third members (including Detroit Lockers), nodular iron or aluminum castings, axles.  All there on-line plus you can price it out right there.
  If I was to buy their third member with traction lock, and a pair of axles, it would be about $1900.
  And there is a tech line if needed.
   Just another thing to chew on.