I have a 93 945 non turbo with heated seats and mirrors. In snow or rain if I let one wheel spin while accelerating the rear differential locks up for added traction. That part is awesome but it then won't unlock when I don't need it and it affects my steering. When it is locked the car pulls hard to one side and can even stay locked at high speeds. It takes a sharp right or left turn to get it to disengage. Does anyone have any ideas what it could be?

Dear dv8oliver,

Hope you're well. Here's a description - copied from an on-line listing - as to how the locking diff works:

"The Locker is a speed sensitive design. That is, it reacts to wheel slip by sensing when one wheel is spinning substantially faster than the other.So, when you're cruising along on clean dry pavement, the locker operates like any regular open differential.

But, as soon as wheel slip happens, going forward or reverse, the locker immediately kicks in. Here's how. The differential is set up with a flyweight governor that responds to differences in wheel speeds, and disc packs that are mounted between the side gear and the case.

Whenever one wheel is spinning substantially faster than the other, the governor spins rapidly, causing the flyweight to open. That flyweight then catches on a latching bracket and the lockup process begins.

During lockup, a self-energized clutch system causes a cam plate to ramp against a side gear. This ramping action compresses those disc packs mentioned earlier. The ramping continues until both axles - and therefore both wheels - are spinning at the same speed. This is full lock, and it prevents any further wheel slip.

The entire lockup process takes about a split second, and is virtually unnoticeable by the average driver. When both wheels regain traction, unlocking occurs and things go back to normal."

Hope this helps.

Yours faithfully,

Spook

Dear dv8oliver,

Hope you're well. It could be that old oil has gummed-up the governor, which responds to rotation speed, and locks the differential, when it senses over-speed. When the over-speed condition ends, the governor needs a "shock" to unlock.

The first step is to drain the gear oil - which likely is factory-original and doesn't owe you a penny - and replace it with a synthetic gear oil, e.g., Mobil 1.

Before seeking a replacement differential from a salvage yard - I doubt a re-built is economic - the cost of two quarts of gear oil, is worth risking.

Hope this helps.

Yours faithfully,

Spook