what's you opinion on a locker unit

Mosrite · #1 (**permalink**) 02-19-2005, 08:38 AM

I've got a Ford 9in rear, have been thinking about getting a posi in order to burn some double lines. My car is a driver and I don't take it too the track or slalom, but I still want to have a little fun at stop lights. I was given a Powertracks Lockright from a friend still in the box. It was for his Bronco's 9in rear. Can I use this. What would be the advantages/disadvantages. Something I was reading made it sound like this unit actually isn't bad for turns because the tires will adjust rotation in turns. I've heard locker units are noisy though, but my side pipes may drown out any sound... Any help? thanks

blykins · #2 (**permalink**) 02-19-2005, 09:23 AM

A locking diff is good for straight line stuff. Don't expect too good of performance in the twisties though. They're known for being unpredictable upon exiting a curve....They could lock up early and under full throttle acceleration coming out of an apex, you'll have lots of push.

If you're just doing the light to light stuff....it should be fine.

Yes, they're noisy.....but Cobras aren't made to be quiet.

This unit will work in your car if your axle splines match the diff splines....for instance if your diff is 31 spline and your axles are 28....it won't work.

Tinker51 · #3 (**permalink**) 02-19-2005, 09:26 AM

Well I don't have a ton of time with one and it all comes from a early Bronco but here is my two cents worth.

They do make noise, but I doubt you could hear it over the pipes. They work great for an off road or race applications but I am not so sure I would want one in a street car. The few times I have driven said Bronco on pavement have been interesting. The first time it breaks loose when you are going around a corner you will swear on a stack of bibles that you broke something. Loud bang that can be felt through the frame that makes the whole truck jump. Maybe the lighter Cobra won't do that. Again, I have only driven this Bronco on pavement three times but it did it at least once every time I drove it.

Ron61 · #4 (**permalink**) 02-19-2005, 01:17 PM

What all the above said. I went to an Eaton unit with 31 spline axels and had it built up some. It works great on the road course but has enough give that you don't get that wind up of the inside wheel on a short turn. I didn't like the solid locker that I had in another car at all and replaced it with one of the Ford posi-trac units. And the lighter Cobra will do that. Even with my Eaton, when in my driveway I can just hear the left rear tire scoot a little when I turn real short but don't have that big bang at all.

Ron

trularin · #5 (**permalink**) 02-19-2005, 07:09 PM

It is not designed for street use and will cause problems driving.

Put this in and it is no longer a differential.

Just my $0.02

Mosrite · #6 (**permalink**) 02-19-2005, 07:51 PM

so i would want to just get a regular posi unit?

blykins · #7 (**permalink**) 02-19-2005, 07:56 PM

I would....unless you're strictly going to have a drag car.

I have an Auburn Pro in my 9".....It's tight....but it's quiet and it won't slip...

Ron61 · #8 (**permalink**) 02-20-2005, 06:09 AM

Also if you are going to be really banging the unit a lot, they can be built up as I had my Eaton when I had it installed. I ran a standard Ford posi for 5 years and one day the left wheel hit on a really sticky spot while the right wheel was slipping and that tore the stock clutches up. So I decided while I was having it replaced to go with a stronger unit and then have it built some. I didn't go for the titanium gears though as the cost wasn't worth it to me. Also my 1969 Torino Cobra which is a lot heavier has the Ford traction-lock posi in it that came from the factory and it is still just as good as it was new. I only had two choices back then. The locker or the traction-lock and after my experience in another car with the locker, I would only want one for straight line or maybe off road where you are climbing steep hills.

Ron

tpiini · #9 (**permalink**) 02-20-2005, 06:32 AM

Although my Cobra is built "up", as are most, I'm a weenie driver and only get on it when there's no chance of hitting anything should I get it sideways.

That said, I have an Auburn locker with 4.57 gears in a 9". The only time I ever know it is when I'm turning tightly at parking-maneuver speeds. The car will hop a bit the make noise as the rear goes through the cogs.

Oh, and I know it's there when I lay a nice even pair of stripes on the pavement.

I didn't build mine, but if i were to do another I'd probably go with a straight posi instead of a locker.

webebob · #10 (**permalink**) 02-21-2005, 06:40 AM

Saturday I helped a friend pull a locker out of his cobra's 9".

I may be speaking out of turn here, but I think he would love to sell it. The locker is in fine shape. It just is an annoying street diff.

Any takers?

If so, he is a cc member, I'll tell him to check the thread.

FlakMan · #11 (**permalink**) 02-21-2005, 06:51 AM

I have a 9" 31 SPLINE DETROIT TRU-TRAC limited slip on by Mustang. It's a 31 spline Detroit Tru-Trac worm gear style posi traction unit for 9" Ford rearends. It will flat out hook up and launch you. Best straight line work though is a 9" 31 SPLINE DETROIT LOCKER, This a full on locker.

I have a the Currie Stage II Muscle Car rearend in my stang. It is designed for higher horsepower, more abusive street applications. Stage II includes the heavy duty 9" Ford housing and 31 spline performance axle package (CE-0005A), leaf spring pads mounted (CE-7001), Explorer disc brakes (CE-6012) , 3rd. member built in with the 9-Plus nodular iron sportsman case, 9-Plus nodular iron big bearing pinion support, Tru-Trac Differential, gear ratio of your choice, and 1330L yoke. This is a fully assembled rearend that is ready to bolt in!