Wayne O

I believe I read the F55 system in the 2007 C6 was improved to offer a greater differentiation between the two settings. I also recall reading there was a re-flash for the F55 system.

With the magnetically responsive F55 suspension system, the state of the MR fluid changes in proportion to the strength of the magnetic field applied. I also realize the F55 system reacts in relation to various inputs such as braking, steering, throttle, lateral acceleration, relative position, relative velocity, vehicle speed, steering angle, lift/dive angle, yaw rate, road inputs, etc. to provide variable force resistance.

What exactly is the F55 re-flash for? I don’t recall reading about any problems with the F55 suspension system so if the re-flash isn’t corrective, is it to improve system performance?

Does the F55 re-flash alter the parameters of the various inputs to increase dampening resistance and/or does it change the electrical current to increase the magnetic field to alter the MR fluid to an even denser state....yielding greater performance-oriented dampening?

Zig

Landru

Might do both, Wayne.
Changing the computer's register values (within the F55 program) would conversely change the output current controlling the dampening.

I'm curious as to why reflash of the entire program was required to start, unless reflashing one (or more) register values couldn't be accomplished without doing 'em all.
"Old" EPROMs used to work like that, but I'd have thought the PROMs used in todays cars would've been of the EEPROM variety.

Now this is a question for "Shopdog" if ever there were.

Mel 2001

jimmie jam

i don't know about a reflash but i will tell you that with my 07 F55 you can tell immediately when you switch from touring to sport, even on a "regular" street. i'm not sure that prior years were that noticable so it may be different.

Miaugi

The Clevite Kid

Shopdog does not have the F55. He has the base suspension with Z51 anti-sway bars, and Bilstein HD shocks. He is QUITE pleased with his setup.

Miaugi

Maybe so, but we're betting he can shed some light on this issue regardless whether his car has F55 or not.

Wayne O

I can discern a difference even on my 2005 F55 system....it's not huge but it is a noticeable difference. Perhaps part of the reason the difference between the tour and sport modes is 'less' is that the inputs to the system are remaining essentially the same. Many factors affect the suspension system....if these factors are fairly constant, the feel of the ride will remain somewhat constant as well. The application of the magnetic field changes MR fluid from a liquid state to a semi-solid state in proportion to the strength of the field applied. In sport mode a greater magnetic field is applied proportional to the many inputs the system receives. If these various inputs remain constant, you will not feel the maximum results of the system.

Again, I wonder what the F55 re-flash is for....to correct some problem I am not aware of or if the re-flash is to enhance performance of the system itself by means of altering the input specs and/or the electrical current/magnetic field.

Hopefully, some of the more qualified tech people will have some knowledge about this. Overalll I'm very happy with the F55 system but if a re-flash would enhance it to an even higher performance standard, that would be great.

RJMan

TTT

I'm interested too.

Mel 2001

ZO6Gal

Can a reflash be done if the car has been tuned? I don't want to do anything to mess that up. Thanks.

shopdog

Sorry, I don't know the answer to this question.

Cosmo Kramer

RJMan

Anyone had the F55 re-flash please jump in. I'm interested in the A6 tranny re-flash too or do either of these even exist?

RJMan

TTT
Anyone?

BigGeek

Usually there's a very large "lookup" table that has parameters for steering, accelerator/brake peddle, g forces, and road conditions (bumps) and so on and so forth. It's not just a simple register change. And changing one spot in the table could throw the adjoining spots off, making for a rough transition.

As I remember the change was actually done for 2006 models to make a greater difference between sport and tour modes.

Zig

how would you compare this to what one get with the z51 bars on the f55 ?

BigGeek

Sorry I couldn't tell you.

I did drive a 2005 vert with F55 for 2 days. It was definitely hard to tell the difference unless you hit a real bumpy road. Even then I considered the difference minimal.

But in the end I got the Z51 for my own car.

Wayne O

I definitely read they changed the F55 system to provide a greater differentiation between tour and sport modes in either the 2006 or 2007 model year. I did read (somewhere here in the forum) there was a re-flash for the F55 system. It seems a mystery so....

I stopped-by my local dealership yesterday and spoke to my service advisor. I asked him (and I put it in writing) when he had time, to confirm whether or not there is an F55 re-flash and assuming there is one, to find out exactly what it does.

I hope to hear back from him later this week.