Bought my 06 P74 used. Car has a "traction control" on/off switch. Want to know if ti has an LSD or not. How to check?

If it does not have one, what am I looking at to get the dealer (or me under the shade tree) to install one?

-Cabby

99.9% of me says you dont, because civilian crown vic's only caem with 2.73 or 3.27 open rear ends.

however, just go in the street and light em up. Simplest way to know if you have a limited slip.

Door Sticker Decoder <<<<< -click-

They no longer use an axle tag and the L code for some of the Ford 8.8" rear ends. My GT has a sticker that says "SYNTH LUBE ONLY 3.55"

jack the rear of the car up so both rear tires are off the ground. (Make sure to block the front wheels).

with both rear tires off the ground rotate one of the rear tires. If the tire on the other side spins in the same direction then you have an LSD but if it doesn't then you don't

I have seen an explorer diff with both. the syn only tag and the gear tag. Its a 2001 Explorer sport.

My tag is wrong... I wouldn't trust them...

Traction control is electronic and uses the ABS (low speed) to modulate the spinning rear wheel's brake caliper along with torque modulation by the PCM to reduce wheel slippage.
It is an independent option from traction-lok (LSD)

Traction-lok was not available for your model regardless of gear ratio, so you won't have it.
I was optional for fleet/CVPI models for both the 3.27 and 3.55 axle ratio for your year.


You can purchase one from adtr.net, installation will probably be ~$200-$300 since the pinion won't be touched..


...driveshaft/transmission also needs to be in neutral if it has an LSD for them both to spin. If open it will spin the other side the opposite direction even with shaft locked/park.











The AXLE tag should always be right. The door sticker, OTOH, can't always be trusted. Most who have found discrepancies with the axle tag bought their cars used, and/or with higher mileage from fleet use (police) so the rear axle had probably been opened up at some point. Though, it's not completely impossible but would be extremely rare.

On my car the door tag and axle tag say 3.55 no locker... but when Roylpita ran the OASIS on it 3.55 locked is what comes back... dunno.

Pull the cover and look for the S-Spring. At 100k, you might want to change the gear oil anyhow.

I need to change my fluid and replace the clutches..

Whats and LSD and install cost? Would I need to go to 3.27 gears to be able to use it??

You just swap out the differential carrier. Install cost in new parts:

$230 for new Traction-Lok
$30 for new carrier bearings and races
$10 for new ring gear bolts
$24 for new synthetic gear oil (Redline 75W-140)
$4 for 3 oz of XL-1 Ford friction modifier

Do the 2006 Vics get 31 spline axles? I think Ford went to 31 spline for 2005-up, just like the S197 Mustangs. If so, you cannot use take-off Traction-Loks from 99-04 Mustang GTs.

It will probably cost around $300 for labor at a shop. You don't have to have 3.27's. You could keep your 2.73's if you like. But, if you are thinking about uprading gears in the future, it would be best to get it all done at the same time. You would save yourself the labor costs a second time.

Lick the stamp.