Pros & Cons POSI vs. Traction Control

[jaywish]

I have had rear wheel drive (rwd) cars with open diffs (od).
I have had rwd cars with posi diffs.
I have had rwd cars with posi & Traction Control (tc).
I have never had a RWD cars with an od and tc.

Like most things, I see posi as being a bit of a tradeoff. Where I live I think it is worthwhile tradeoff due to snow. It is also a worthwhile tradeoff when you have a car powerful enough to warrant putting the power to both wheels so you can maximize acceleration. Also if I lived around muddy roads I think I would find it a worthwhile tradeoff.

The downside to posi is cornering under power, particularly on rough surfaces. It is easier to fishtail. An open rear keeps the power going to the outside tire.

Now my questions:

How good is tc by itself in the snow/mud?
I don't know how it helps with straightline acceleration either?
Also how does it effect turns under power?

Jay

[SVT98t]

TC is okay in my Town Car. It's an open diff. It's doesn't help much if you're stuck, or getting into some bad slush.
Acceleration sucks in the snow. It keeps taking power away when I need to go.
Essentially, I turn tc off in the city, on for the country roads outside the city.

-ryan s.

[johnunit]

Tc doesn't help you find more grip, it just cuts your power enough that you don't overpower the grip you have.

[gadget73]

If you put a limited slip into a traction control car, it basically defeats it. If you lose traction, both wheels will spin and the electronics aren't going to clamp down the brake on one side. It may drop out the throttle on stuff new enough to be fly by wire, or it may not. Before fly by wire though, all it did was apply one brake. You could mash the gas to the floor and it couldn't do a damn thing about it.

[88Vic]

Posi over TC anyday. TC sucks in snow, it just makes you bog down and get stuck, but spinning tires keeps you moving. The extra grip is always worth it, even in corners you'll have more traction and control. If you're spinning around a corner, you're on the throttle too much, in snow you should be on the throttle only enough to make the turn, you should be taking it very slow then more on the gas after you straighten out.

[jaywish]

with a posi & TC car the tc seems to kick in on impromptu burnouts Which can also be problematic in snow.

As far as handling on the turns I was more thinking about dry or wet conditions, maybe dry at higher power

[SVT98t]

I just turn it off when necessary.

-ryan s.

[lincolnlarry]

My 04 Town Car was open diff with TC. It was basically like SVT said plus it didn't like hills in the winter. Seemed like you had to kill the TC in any deep snow situation. Upside is it didn't fishtail during normal driving on slick roads.

[IPreferDIY]

I have open diff and tc in my 2000 MGM. There's only two things I like about tc. First, it lets me know when the wheels are slipping. Second, if I've been lazy with clearing and salting my up-slope driveway, it prevents high revs and wheel spinning on those occasions when I have a chance of making it out. Otherwise, I just throw down some salt to give me better traction.

I work from home, so I usually get to drive at my convenience. In the winters, I only do city/highway driving, and I generally avoid bad conditions. I just use all-season tires, and they've been fine with this approach.

The only time I had significant traction issues on the road was during our first major snow dump this winter. I had things to do and decided not to put them off. I hit a spot on a hill that must have had black ice, and, for the first time ever (apart from my driveway), I couldn't go anywhere with the tc on. The tc was absolutely useless. When I turned the tc off, I was able to spin my way out of that particular spot. I don't like having high revs and spinning wheels, but it was essential on this occasion. I experienced the same thing in a different spot on level ground on the way home and had to turn off the tc again. I would guess that everyone would agree that tc is useless for getting you through challenging slippage situations.

AFAIK, tc would not have any effect on straight line acceleration or turns under power unless one of the wheels actually started to slip. It only works when you start to lose traction. It doesn't actually contribute to the traction until then.