There have been many threads on this, but when it comes down to replacing the F45 shocks, seriously consider the F55 upgrade.

I went back and forth (86,000 miles on my 2000 C5 convertible with the F45; 50k on the fronts; 85k on the rears).

It's worth every penny -- do not be dissuaded by the cost. The package includes the computer (plug and play, no codes). Install is also DIY with jacks and stands. Having a friend like I did under the car helps.

Remember, the F45/F55 suspension settings change information to the shocks not only the based on the setting of the switch at the console, but also the information being transmitted by on throttle position, yaw sensors, speed, gear, etc. The F55 upgraded computer and algorithms make the car feel like a completely new car (it also firms up the steering) depending on the information received.

None of the other shock replacement options offer so much.

 

So how much is the F55 upgrade?

 

The kit is part number 12499507

you can search the "usual suspect" sites for pricing ..... such as

http://www.gmpartsdirect.com

 

For what they want for those shocks, they better do a lot more than just firm up my ride.

GM MSRP $2994.29
gmpartsdirect $2179.84

 

I got mine from Bob at Fichtner Chevrolet, for under $2,400, which includes the computer and wiring.

When you look at GM Parts Direct, note that they will be almost $400-600 in "shipping," depending on when you ask.

 

Yeah, they actually do more than just firm up your ride ....

The F55 suspension is also known as the MSRC (Magnetic Suspension Ride Control) system. Developed by Delphi for GM it is considered one of the most sophisticated suspension systems in the world.

Chevrolet is using it as the ONLY suspension system for the new ZR1 Corvette ...

Ferrari has licensed the system from GM and uses it for the 599 GTB Fiorano .....

http://www.ferrariusa.com/

Audi has licensed the system from GM and uses it for the R8

http://www.audiusa.com/audi/us/en2/n...s/Audi_R8.html

Honda (Acura) has licensed the system from GM and uses it for the Acura MDX (they try VERY hard to hide the fact this is American technology in a *** car)

http://www.acura.com

If you'd like to learn more about this system read this article (scroll down after the page opens to see the start of the article) ...

http://www.corvetteactioncenter.com/...s+the+50th+Car

GM has some of the best technology in the world ..... but their marketing department should be taken out and shot (along with the engineers who did the column lock for the C5 ....). It is sad how few people know the technology GM can put on the market.

 

 

With the exception of ride selection changing from tour, sport, performance to just tour and performance, why wouldnt I change to C6ZO shocks

On my F-45, I seem to use either tour or performance anyway

I guess what im looking for is what did you notice differant and could it be just that you got new shocks and that made a differance.

I do like the tour ride when taking a cruise and do like the performance when Im playing.

I cant tell much about sport lol

 

Phil --

Around the NYC area, we have potholes all year long, and especially in the spring. "Touring" is a life saver and a car saver -- I'm convinced that over 86,000 miles, my convertible has not been as beaten up thanks to the F45 shocks as it would otherwise be with the Z51 -- it's remarkably noise free and tight for that mileage.

A couple of things were noticeable, and I think I remember the car pretty clearly on the OEM standard feel for the F45 -- that's why my fronts were replaced under warranty when they went south at 33,000 miles. I could really feel it, and it was scary.

The F55 new is a lot more absorbent on bumps and jarring potholes/manhole covers than the F45 new -- It glides "over" them than dropping into them softly like the F45 did. On medium dips, there is very, very little vertical displacement in the body.

In Sport/Perf mode, the F55 has considerably less body roll than the F45 (I played around with various sway bars from stock to Z06 with the F45 so I know the corners and the clearances I had, even when new). Where the front dam used to scrape it doesn't anymore, for example.

In high speed turns (88 mph just today), the F55 is much flatter through an S-transition than the F45 -- this is a series of turns (one way) that I've been taking for twenty years in everything from the then new C5 with the F45 to a '96 Impala SS. In other words -- I know that section of the road pretty well.

Finally, just the computer is about three times the size of compared to the little F45 one. It also has cooling fins that the old one does not.

The F55 is a whole different ball game; it's not just a "new set of shocks." BlackZ06 hit the nail on the head above. It's like having a Cadillac, ZR1, and Ferrari on hand with the flip of a switch.

 

Much better explaination.

10 years in NYC, I remember the pot holes all to well.

Sometimes I dont use my car enough, and forget what it does and doesnt do.

I do miss the fun roads of the NorthEast.

 

I just had the F55 ride controller disabled in my car, as the shocks needed replacement and I wanted to go with something other than 1k per corner shocks.... I'd be willing to part with the ESC and the suspension position sensors for very little. Send me a PM if you're interested.

 

So other than putting in new computer and new shocks, what else needs to be doneÉ


(OT...CAn some one tell me what Im hitting on my keyboard to make my questions marks look like this `É` wtf)

 

The kit (shocks and computer) is all you need to "upgrade" from the F45 to the F55 system. If you read the article I linked to above you'll get a better idea of how the computer is faster, and how the shocks adjust electronically rather than mechanically. Those are fundamentally the two changes over the F45 system. In essence GM with F45 had the base technology for this system .... what they lacked was a shock that could "react" as quickly as a computer ..... with the magnetorheologic shock they now have what they need .....

This is the suspension of the future .... you will see other automakers (besides Ferrari, Audi, etc) either licensing it or developing similar systems. With the computing power available today this is the next logical step ... let a computer manage the suspension system (just as computers have come to manage the engine/transmission since the 1980s) to give you the best of both comfort and performance .... with you choosing which way to bias the system .... comfort, or performance.

As to your "?" issue ... what operating system and character set are you using ??? Character set issues get ugly really quickly ....

I was in Europe attending a database conference a few years ago and standing next to a coworker who was talking to a customer. Customer says "What happens if I have a database in Germany running on a Unix system using a German character set (umlaut supported) and a user in Norway inputs a customer address using an Apple computer .... what does a user in China see as the address on his Windows computer ....????"

As my buddy turned to me for help I ran screaming from the room ....

THE reason English (US/UK) is becoming (may even already be) the language of the world is because of computers ..... picture a "Chinese" keyboard ..... approximately 40,000 keys ????? Not gonna happen ....

English and its character set is the language of the world ....

 

You'll also need the wire harness for each shock (F45 does not plug into the same location on the shock as the F55 -- it does on the car, but not on the shock). Total of four harnesses.

 

Is the console switch replaced with 2 position switch in the F55 kit?

 

There is a 2 position switch. I'll happily give up my 2 position switch for a console piece without a switch at all.

Seriously, I want to remove every vestige of the F55 from my car. So, if someone can indicate which harnesses are needed, those can go with the Electronic Suspension Control Module, the Ride Position Sensors, and anything else I can safely pull off.

 

For the same or less money of the F45 or F55 you can get PFATT coil-overs.
The coil-overs offer a huge range of adjustments (soft to hard) just about all of them an improvement over the above mentioned factory setups!
Setup correctly the coilovers offer superior ride and handling!

Plus, you don`t need to replace the computer, just run a small inexpensive simulator at each corner........

And yes, I know this first hand, not parroting what others have said....

 

Rick --

1. You don't need to run simulators -- you can disable the F45/F55 option in the BCM with a Tech II.

2. I like the fact that I can switch settings on the shocks while I'm driving -- the potholes stop, and the twisties start -- I'm set. Correct me if I'm wrong, but with the Pfadt shocks I have to stop, get out, crawl under the car, and start wrenching. Even if it's raining. Yes?

3. I get tired of the ride while on a trip, I can set to touring at 65 mph. While in between exits on the Northway. I can't do that with the Pfadt, can I?

 

Once you get the spring height/rate set you will not need to mess with the springs. From there you can adjust "just the shock settings/valving" which is adjusted from the top via allen wrench.

The beauty of coil-overs is that you can go with an "all around" set up which absorbs bumps/potholes much better than leaf springs and still retain superior handling! That`s the reason I swapped, you get your cake and you get to eat it too........

Comparing the differences of the settings on the adj shocks, the above mentioned coil over set up still offers superior ride and handling without the need to adjust.
The only scenarios I can see needing adj on the coil-overs would be if you`re a "hard core canyon carver," or if you track the car.....

 

I do like the turn of the switch inside the car better than turn of the wrench from the outside.

What kind of sway bars do you have ?

I did the ZO6 sways and bushings