Advice or tips for my 9" upgrade

[roddster]

  This is going in my 67 clone so take it easy eh?  428 with a C-6  (That is NOT changing), It'll be a cruiser, not a race car.
   Kind of the plan: 3:50 gears, all new bearings, equa-lock center section with 31 spline side gears, new Moser axles.
   Not locked on the 3:50 gears, don't want to do 3:89 or 4:11's
   Summit sells the Yukon type center section.  It has the rebuildable plates for the equal lock.
  OK, suggestions welcome

[Krelboyne]

Equa-lock? No, you want a Detroit Tru-Trac.

[Royce Peterson]

Personally I prefer a Detroit Locker because they are quiet, maintenance free, and don't require a friction modifier. The Equa Lock was retired by Ford after 1967 model year because they just wear out too fast. The 4 pinion Traction Lock came about in 1968 and was slightly better but not much.

I really think the Equa Lock is marginal if you have a small block. With a 428 it's not any good.

  This is going in my 67 clone so take it easy eh?  428 with a C-6  (That is NOT changing), It'll be a cruiser, not a race car.
   Kind of the plan: 3:50 gears, all new bearings, equa-lock center section with 31 spline side gears, new Moser axles.
   Not locked on the 3:50 gears, don't want to do 3:89 or 4:11's
   Summit sells the Yukon type center section.  It has the rebuildable plates for the equal lock.
  OK, suggestions welcome

[2112]

Do they make a Torsen for a 9"?

I think they are considered the best by most road racers.

[roddster]

  I had a Detroit Locker in my former 66 Mustang.  Didn't like it, so, no way on a locker.

[Rukiddin]

I agree with Royce.....The Detroit Locker made recently is quiet and ultra reliable. You probably had the early DL that had a rough ratchet on corners. Then again,if just cruising and staying off the gas (yeah,right) go with Ford Trac-Loc . You won't break it with an auto trans

[gt350hr]

  No such thing as a 9" 31 spline "equa lock" , ALL "clutch type" 9" 31 spline units were Traction locks , built after '67.

[Kent]

I think Ford Racing had a Torsen for 9" and I had one in a 8.8" and believe me that was the best differential I ever had for drifting, cornering and accelerating also 1/4 mile was great with the torsen.

[Kent]

https://torsen.com/product/ford-9-31-spline-t1/

[2112]

https://torsen.com/product/ford-9-31-spline-t1/

Thanks for that Link. I have a Torsen in a different GT500 (8.8 rear) and it is incredible at putting power to the pavement coming out of a turn.

Zero noise, ratcheting or any other issues.

[vtgt500]

     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.

[2112]

That Torsen direct site is new. From their info page;

Welcome to Torsen®. Since 1984, we've provided class-leading helical gear, torque-sensing differentials to premiere auto manufacturers. From the military AM General HMMWV to Audi Quattro sedans and SUVs, Torsen differentials provide the traction and handling that you need. Enthusiasts will recognize the advantages, with respected performance cars like spec-series Miatas, the Mustang Boss 302, and the recent Chevrolet Camaro Z/28 all running Torsen® products.

Our seamless operation integrates flawlessly with modern electronic chassis control systems, like traction and stability controls, as well as anti-lock braking. That means that your chassis systems work less often, with less intrusive behavior, and the overall experience is even better. Safety, performance & reliability – progress requires traction, and that is what we deliver.


Mine is the Ford Factory installed unit.

[1109RWHP]

I took out a NASCAR version Detroit Locker and put a Detroit Truetrac in my 9". Much smoother than any Detroit locker street or NASCAR version.

[Royce Peterson]

Nascar racers use the H series Detroit Lockers which are quite harsh and noisy, much like what Ford used from 1970 - 71. The ones made after 1979 or so have a different locking pawl assembly and spring. So any regular series Detroit locker made in the last 40 or so years is quiet and smooth.

Stay away from the used H series Detroit Lockers they are often for sale on eBay for $250 or thereabouts as Nascar take offs. The Nascar boys replace the axles, bearings and differentials every race.

I took out a NASCAR version Detroit Locker and put a Detroit Truetrac in my 9". Much smoother than any Detroit locker street or NASCAR version.

[gt350hr]

  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