9" TracLock Limited Slip Rebuild

olddog · #1 (**permalink**) 03-08-2011, 05:52 PM

I think I have a TracLock carrier. It has clutches in it. I'm looking for information on how to determine what might be wrong with it and how to rebuild it. Like what to measure. How can I tell if the clutches are worn?

The reason I pulled it, is that I started to feel it locking and unlocking. Worse than a chatter. Almost like a clunk. I first noticed it when I backed up after setting a few days. Then this fall, it started doing it on right turns, with light power to it. Step down on the gas and it would quit. Within another 25 miles, it started doing it turning left or right. I even felt it coming to a stop sign on a straight stretch. Just pushing it in the garage, as soon as you start a turn you can feel the car clunking.

I don't really see anything wrong with it. The spider gears look good on the sides where they touch. The tips of the gears, where they do not touch anything, have faint lines. Perhaps machine lines from manufacturing, but not sure.

fordracing65 · #2 (**permalink**) 03-08-2011, 05:57 PM

if you do a burnout with it and both wheels spin its fine, you said you have it out, sometimes when they lock and unlock they make a clunk when engaging. I did a tire change and my spring didnt set right. After about 30 miles it went clunk and set back into place, it could be something else.

DAVID GAGNARD · #3 (**permalink**) 03-08-2011, 06:52 PM

There is also an additive you should put in the rear end oil with a Limited Slip 3rd member, it is made specifically for this and will reduce the "chatter" and make you LSD work better.....if it is out and apart, look at the clutches, you should see a "pattern" on the clutches itself almost identical to a clutch disc, if the clutches show no pattern and are smooth, they are worn and I would replace them, otherwise,put it back in the car and add the LSD additive (avaliable at any Ford dealership or parts place) with the rear end oil.....
David

redmt · #4 (**permalink**) 03-08-2011, 07:26 PM

If all the frictions and steels look pretty much the same , run it. Make sure the springs are all OK. When they really start to get bad they will waddle when you back up. All of a sudden you will find it a real chore to back up for any distance in a straight line as the torque will continually shift from side to side.

Rick Parker · #5 (**permalink**) 03-08-2011, 09:48 PM

Check the "Hat" for hairline cracks in the area machined for the heads of the bolts that attach the ring gear (look very carefully). If they are present they will allow the spring pressure to be inconsistant and the hat will eventually fracture, causing huge damage. If you have it apart, time is well spent with a die grinder smoothing out all the sharp edges and corners.

olddog · #6 (**permalink**) 03-09-2011, 04:02 PM

Quote:

Originally Posted by DAVID GAGNARD

look at the clutches, you should see a "pattern" on the clutches itself almost identical to a clutch disc, if the clutches show no pattern and are smooth, they are worn and I would replace them, otherwise,put it back in the car and add the LSD additive (avaliable at any Ford dealership or parts place) with the rear end oil.....
David

The clutch disks have the cross hatch showing. Is there any way to find out the spec on how thick they should be or the total hight of the stack? The clutch pack is setting on shims. I assume there is a reason a shim was added. Not sure if it is for total hight or to adjust spring pressure.

They look good to me, but I'd like to be sure. I don't want to waste money on parts I don't need, but I don't want to have to take it back apart either.

olddog · #7 (**permalink**) 03-09-2011, 04:04 PM

Quote:

Originally Posted by Rick Parker

Check the "Hat" for hairline cracks in the area machined for the bolts that attach the ring gear. If they are present they will allow the spring pressure to be inconsistant and the hat will eventually fracture, causing huge damage. If you have it apart, time is well spent with a die grinder smoothing out all the sharp edges and corners.

I am assuming you are talking about the carrier only. Not the housings.

olddog · #8 (**permalink**) 03-09-2011, 04:11 PM

The gasket between the center section and the rear end housing was leaking. I do not know if it had the friction additive in it, as I bought it used, but I assume it did. I question if the additive may have leaked out over the long winter months when it sits. It should stay mixed with the oil when you drive it, but setting for 4 months? Maybe. Any opinions?

zrayr · #9 (**permalink**) 03-09-2011, 05:20 PM

Quote:

Originally Posted by DAVID GAGNARD

There is also an additive you should put in the rear end oil with a Limited Slip 3rd member, it is made specifically for this and will reduce the "chatter" and make you LSD work better............."

your Ford dealer sells exactly what you (likely) are needing. It's sold under the Motorcraft brand label.

Z.

DAVID GAGNARD · #10 (**permalink**) 03-09-2011, 06:33 PM

"Generally" speaking,if I can still see a decent pattern on the clutches, I don't change them, they are still good.....not sure of any or exact diminsions of the clutch pack, it's put together with shims to fit the carrier.......kinda trial and error,or better yet, expirence.....

My car sometimes sits for 2 or 3 months without moving and when it does, it will occasionally make some weird sounds, seems to go away once I get down the road a few miles and the oil/gears warm up and begin working properly again........
if your not sure, take it to someone that has done these before and let him check it out......
They are pretty stout and can take a lot of abuse. The one in my car came out of my dad's truck, it had 85,000 rough miles on it then and all I did was change the ring/pinion and put it in my 65 fastback...since then, it has seen over 100 1/4 mile drag passes, at least that many hard stop lights starts,about 1500 to 2000 miles on 3 road courses and 25,000 miles of city/highway driving....I change the oil in it every 10 years whether it needs it or not!!!!!

David

olddog · #11 (**permalink**) 03-09-2011, 08:41 PM

After days of searching and reading, I found these instructions on rebuilding Traction-Lok.

I am pasting a link for anyone else who may want to work on one. You may want to print or save a copy of this PDF file before it disappears.

http://www.miraclemustang.com/photog.../V2D749056.pdf

Now all I need to do is find a Shim template that they show!

Rick Parker · #12 (**permalink**) 03-10-2011, 02:53 AM

Yes the crack can be in the Hat/Cover. As David described the mesh pattern is to allow for lubricant between the surface of the friction disc and the smooth metal disc, hence the scontrolled slippage. If the friction discs are worn (pattern gone) they will be thinner, causing the stacked height to be less, thus reducing sping pressure and excessive slippage. Trak lock is not advised for drag racing, it will burn up the clutches in short order. It was devised for controlled slippage in OEM configuration, Deroit Locker works for drag racing, but is rough in everyday driving in a light vehicle such as Cobra Replica, because of the harsh locking qualities.

undy · #13 (**permalink**) 03-10-2011, 04:38 AM

I dumped my 9" LSD for a Detroit True Track and never looked back. It's a great "posi" and it will NEVER chatter our slip.

mdross1 · #14 (**permalink**) 03-10-2011, 07:03 AM

Done right the TracLoc is a good choice.Been rebuilding differentials for a lot of years and set up for it.Having stub axles to check lockup break torque helps.The clutch pack should hold 180lbs minimum.Using the additive is mandatory on a clutch type posi,it can be purchased in a lot of places.Not brand specific.

olddog · #15 (**permalink**) 03-10-2011, 08:29 PM

I just spent some time looking things over (with my glasses off so I can see up close).

The hat is in good shape. No cracks. It might be steel.

I measured the thickness of the clutches. They are between 0.058 and 0.060 inch. The manual says replace if less than 0.085" thickness.

I looked the spider gears over real close. This time I could see better. I can see and feel wear patterns in all the teeth. Some feel like 0.005" deep. The spiders slide up and down on the pins a long way--maybe 1/16". Backlash by eye is around 1/32". I think they need replaced, too.

olddog · #16 (**permalink**) 03-10-2011, 08:36 PM

Quote:

Originally Posted by undy

I dumped my 9" LSD for a Detroit True Track and never looked back. It's a great "posi" and it will NEVER chatter our slip.

Undy, I have looked on Eaton's web site and read up on the True Track. I like what I saw. Moser claims their WaveTrac is better yet, but do not show how it works - patten pending. They claim it will transfer 100% torque to the wheel on the ground with the other wheel in the air.

I hate to spend any more $ than necessary right now. I'll see what parts cost.