Hedges

So now that its installed, give us some feedback on it.

whoover

Your description does not match my experience with the OEM LSD. Floor it and it goes, with much better transfer of power to the road. I'm not even sure I can imagine a mechanism for the kind of lag you describe.

avery.whss

maybe my OEM LSD is screwed up, doesn't make any noises though...if i floor it, the tires just break loose and the ESP light blinks like crazy (in esp sport) and then the power gets cut for a few seconds...thats not normal you're saying?

whoover

Yes, it helps with power laydown in straight-line situations, but for me it's most important in helping connect all that power on twisties. I live on a mountain road with a few badly banked curves. There are some where my ESP light would come on unless I really slowed down. Now, I can actually accelerate through those curves with complete control.

whoover

It's your ESP cutting power, not the differential. Why is your traction so bad is the question. Tires? Are they in good shape. Stock size? Larger rears than stock could be throwing off the ESP calibration and making it jittery.

avery.whss

tires are good shape...using p-zero neros...better then the PSS..my car just ate the PSS's apart they crumbled within like 2-3 months, that was on stock rims too..right now I'm on VS-160 20's so yeah it's a bit larger for sure..285 in the rear 25 series tire

Ingenieur

If works when ever there is a load/traction differential
a line or a curve

On corners even at low speed I'd get slip
No more
Just hooks and goes

The power is applied more uniformly and smoother
It seems to help steer the rear around corners

Well worth the money and the car is much improved with it

whoover

That's your problem. Those tires are 2.3% bigger than stock.
http://www.tacomaworld.com/forum/tir...5r18-285-25r20

For proper ESP operation (and even wheel geometry) it's recommended to stay under 1%. Anything over 2% will convince the ESP that you're skidding when you're not because the front and rear wheels are not moving at the same speed (according to its computer).

You can either get below 1% or see if somebody with the right Star equipment will recalibrate your ESP.

avery.whss

skinnier tire or smaller rim?

Ingenieur

Been thru this
That small a diffrence makes no difference

whoover

It's the rolling diameter (the "height" of the tire). You can plug in different sizes using that calculator link and as long as the diameter difference is less than 1% vs. the stock size, you'll be ok. If you still have the stock wheels, you can swap those back on and confirm the problem goes away. I'm sure it will.

I always say that if a different tire size worked better, AMG would have gone with it.

whoover

Right. All the 1% recommendations that I posted are fantasies. And the members with this problem (this is not the first such thread) are unicorns.

This member can go back to stock as an experiment. When his traction control problem goes away you can add him to the conspiracy.

Ingenieur

As I proved before it does not matter
Wear alone is close to 2%

Oem
Front 25.4
Rear 25
~2%

Mfg tolerances are >1%

Ingenieur

Link to bosch engineering handbook
Section on tcs
Slip is 5 to 15% before engagement
2% difference is moot
https://mbworld.org/forums/attachmen...9&d=1398864048

whoover

I know your position. But stock front / rear difference is a variable in search of relevance. The ESP is calibrated with stock sizes. It's variation from expected that's the problem.

I hope we get a followup from the member.

Ingenieur

Not my postion
It is technical fact, I did not write the bosch handbook
It is everyone's who understands it


If the system engaged at 1% the car would be indrivable
At 60 mph there is 3% slip ie difference between static od and rev/ mile
The tire changes >1% with 5 psi pressure
It changes or 'grows' with rotational speed

Ingenieur

Rear tire wear new to wear bars
8/32 x 2 = 1/2"
1/2 / 25 = 2%

Do not be ashamed to admit you just don't understand
It's the first step
An open mind can be filled with knowledge
A closed one, well....

Btw: in the tcs software there is no parameter for tire dimensions
It doesn"t 'care'
Only looks at slip, yaw , throttle position, steering angle, etc

If 1% made a difference every turn would set it off
The wheels are turning at different speeds

Jasonoff

Reeer

Yup, that's more apparent now...

Ingenieur

So we have something in common
Neither of us know

And something not in common
I know I don't know
You don't know that you don't know
You are at least certain in your error

But I do know this
Mine was installed better
And John Shepard knows infinitely more about gear boxes than you
Heck, you don't even know shims may be required if the carrier has end play
And they go on each side
The MB site shows shims to adjust carrier side to side play

Jasonoff

Ingenieur

No doubt
You were mot even aware that shims may be required depending on wear

He 's built 1000"s of gear boxes
You hacked one together
Do the math

Are you saying you lnow more than him about gear boxes?
Now that deserves an 'oh really'
If ignorance is bliss you must be a laughing fool

whoover

Have no fear. I understand everything you say. Often I just don't understand why you say them.

The manual includes this note:
Only use wheels with the recommended
tire sizes. Only then will ESP® function
properly.

Any idea why they say that? (Page 67 in the 2013 C-class manual.)

Ingenieur

I say them because they convey insight
Apparently beyond your grasp

Within a tolerance
And it 's not 1%
A 2% wear difference occurs
Are you saying the system senses wear?

Ingenieur

Btw
It says same size as in the techical specs
NOT diameter

So a wider tire with oem od will foul the system
Hogwash

Oem winter tires are 2% smaller in the front
So the tcs is fouled when you need most?
Using oem spec'ed tires no less

Ingenieur

The tcs is working properly
If the tires spin it cuts power/reduces torque

The lsd has nothing to do with this
Niether does tire od

Even launch control systems allow a bit of slip until rolling
5 to 7% seems to be the sweet spot
Keeping it there is difficult

Different tcs settings ( normal vs sport) increase the limits or allowable slip/yaw/etc

Maintaining the front/rear tire od ratio is far more important than absolute od