My 2003 50th AE Coupe (70K miles) came with the F55 Magnetic Select Ride standard -- as did all AEs. Have loved the ride for years, but lately when the selector switch is in the Tour, the car seems to do a hard bottom-out on large bumps. There is a difference in Sport mode (no bottom-out), though the ride is noticeably stiffer (as expected).

I know about the shock stuffers being left in; that's not the problem.

Local dealer checked for codes (none found), tested shocks ("cycled" electronics?) and checked for leaks. I picked up the car and and ticket simply said "no problem found with shocks."

They act like I'm imagining it, but when the car was new it took hard dips and bumps in stride (in Tour). So what could be the problem? Something other than shocks to check?

 

That's the kind of advice I'm looking for. Thanks!
When I dropped in on the dealer, he just checked the shocks (only) as a courtesy... They requested I schedule an appointment to leave it all day (mid-September) and they would look at other possibilities. So I'm looking for any advice here for other things they should check out.

Also, thanks for the instructions to check the codes myself.

Anything else that could have loosened/broken to affect the ride?

 

I'm NOT knocking the F55... just sayin some have deleted the F55 and upgraded to C6 Z06 shocks and love them... it's an option. The dealership is going to want your right arm to replace your shocks...

 

If the dealer later decides the shocks are the culprit, then (from what I've read) replacing them with new F55 shocks will be hugely expensive.

I've seen C6 F55 shocks available, but not for C5 (apparently). Why is that? If other (non-F55) shocks are interchangeable between C5 & C6, why not the F55's?? Some electrical difference?

For those who've switched F55 to C6 Z06, how does the ride compare? That is, does it feel like something between the "Tour" & "Sport" of the F55, or does it lean toward "Sport"?

 

I have the FE1 suspension and swapped out for the C6 Z06 shocks... so, I haven't ever modified the F45 or the F55... having said that. I'm NOT sure this procedure will work for the F55...
IF it won't would someone chime in and tell me it will work for the F45 but NOT the F55 or even confirm this procedure will in fact work for either...as an alternative delete....

https://www.corvetteforum.com/forums...n-my-98-a.html

 

So when you delete with the Tech II ... you can simply remove the sensors and related brackets, etc...? Then install the shock of choice with no codes...

 

Thanks Chuck!

 

I replaced my F55 with Bilstein Sports. It rides like sport mode now.

 

While not an exact parallel, I just swapped out my F45 (70K miles) for Bilstein Sports last weekend.

Handling with the Bilsteins is better than F45 "Performance" mode, yet the shocks absorb bumps much better than the shot F45s on "Touring". Still it's no Cadillac and big problems will give a good jolt, but you can definitely feel the shocks doing their job.

I called around about 6 dealers to do the F45 deletion and none were opposed to doing the procedure, but all save for one were booked until later in the week. That one ended up charging $145. Abel Chevy quoted $100, but their service dept only works weekdays. One dealer thought the procedure was impossible, but was open to checking out the write up posted here. All the others seemed familiar and willing.

Just for reference.

 

I've never experienced the select ride F45 or F55 enough to give any real world thoughts on ride... our car, our first C5 had the FE1 soft ride... yes it was soft... too soft. With run flats it would jar you when hitting speed bump type road conditions... deep dips would make you suck up and go hmmmff, i think it was bottoming out.. it wasn't a shark whack it just bottomed out... at HARD acceleration the tail of the car would set or dip down... I would get wheel hop if the wheels were spinning so I STOPPED that right away..
Swapped out for C6 Z06 shocks that I got from a fellow forum member... and ALL the above is GONE... they ride, handle the varying road conditions awesome... they are NOT stiff, they are firm, they are NOT soft they are forgiving.
I don't know how they compare to the Bilstein or C5 Z shocks either... haven't tried them...but, I don't think I'll ever know because I am TOTALLY satisfied with the C6 Z06 shocks... hope this helps

 

Did the same on our 03 AE convert., and extremely pleased!

Plasticman

 

The F55 shock has an ORFACE inside the shock. It also contains magneto-rheological (MR) fluids. (Check out link below)

http://www.lord.com/products-and-sol...cal-(mr)-fluid

The suspension control module provides an electrical signal to a COIL inside the shock (around that orifice) When the field is WEAK, the fluid flows through the orifice easily without much effort or restriction.

As the magnetic field increases, the magneto-rheological (MR) fluid gets THICK due to it magnetic properties and the shock stiffens up.


Here is a test that you can do: Disconnect one end of the shock. Test the shocks rebound and compression by hand (ignition OFF) and see what it feels like. Turn the ignition ON and set the suspension mode to each setting and test the shock at each setting. It should get firmer as the settings go from tour to performance.



I have never put my hands on a F-55 shock so I can NOT tell you if it nitrogen pressurized or not. Maybe some one who knows can chime in. I know the F-45 shocks ARE pressurized. Found out the HARD way when we broke off a valve on the side of the shock!

The F-55 should also be but don't hold me to that. See if there is a PRESSURE WARNING on the body of the shock. If there is, when you disconnect one end of the shock, it should EXPAND with a good bit of force.

If that shock has THREE different firmness when the selector is changed, the controller and the shock is working. If it were me,,,, I would conduct the test on the remaining three shocks.

IF, you want a used set of F-55 shocks,,, contact VETTE NUTS

(Marc). He MAY,,,,, have some but, its tough to get a good set off a used car.

 

The F55 (at least in my 03) has only 2 settings ("Tour" and "Sport").

Also, they must be pressurized, since they certainly are difficult to compress........

Plasticman

 

Thanks, all, for your experiences and advice. I'll see what the dealer says on the 2nd trip in, though their initial tests didn't indicate a problem.

From what I've read of the F55 shocks dying, it seems that the owners could no longer tell the difference between "Tour" and "Sport". Is that true in all cases?

I'm still able to feel a significant difference between "Tour" and "Sport", so it would seem that the shocks are not dead. Something is going on. The problem is in "Tour," as the car sounds like it is bottoming-out through big dips where it didn't before. "Sport" seems normal.

 

I replaced the F55 shocks on my car, I use the car for track days and road trips so I wanted to keep the versatility of the system. Anyway, there wasn't much difference between modes when the shocks started going. Also the car was very "boaty" yet harsh over bumps. The front end of the car would bounce slightly through some turns.

Hope that helps.

 

SIGH!!!! Going to the STEALERSHIP, will net you either:

SIR,,,, We cant find NOTHING wrong. There are NO CODES and they are not leaking.

OR

We recommend replacing all four shocks! $$$$$$$$$$$$$$$$$$$$$$$$$$$



They are NOT going to try any of the TEST that I recommended unless you are willing to shell out $120+ and hour for them to investigate and that may also cause them to tell you; "We recommend replacing all four shocks! $$$$$$$$$$$$$$$$$$$$$$$$$$$"



Test them your self and decide if you want to get replacements your self at a much lower price than the STEALERSHIP and or install them, your self. See if they are still pressurized and actually change dampening and rebound when you change settings.

The other option is to get rid of the F-55 and run some purpose built performance shocks and maybe up-grade the springs and sway bars to Z51, ZO6 or C6 Z51 equipment. All of which are very doable.

Bill

 

I have to second this. You save about 50% buying new shocks yourself over the internet than through your dealership.

 

My F45s are compressing under their own weight when placed on the ground, the mechanic who replaced them commented about how easily they are "folding", and yet I could still feel quite a difference between the three settings right up until they were replaced. Don't know if that says anything really ..

 

I'm not feeling a "boaty" (bouncy) ride, just bottoms out on "Tour" more easily than when new. I'm also able to distinguish a significant difference between Tour and Sport -- the latter quite firm. So my experience doesn't seem to match yours; or, at least, it says I'm at the earliest stage of failure (or maybe just one or two shocks).

Thanks for your input.

 

The NITROGEN Pressure inside the shock is added to prevent the oil inside from cavaitating when the shock is placed under extreme operating conditions.

Once the nitrogen charge is gone, anytime the shock extends and rebounds, the oil can cavitate as it squeases through the dampening valve orifices and that decrease shocks performance.

Shocks work as designed when they flow hydraulic fluid through the dampening valves inside the shock. Without a pressurized cylinder, that shock hydraulic oil will have air in it and significantly decrease the shocks ability to dampen the wheels motion.

When you test the shock by hand, it still may have some compression and rebound resistance BUT,, When you drive over a really rough road with a LOT of irregular surfaces that cycles the shock through hundreds of cycles per minute, the shock starts to fail as air bubbles and foam form in the oil and you loose wheel contact with the road.

Shocks wear out very very slowly. Then one day when you get a little aggressive in a high speed maneuver and the car looses control or feels like grand dads Buick weaving and bobbing down the road; you wonder why your high dollar sports car handling SUCKS!

When you put new shocks on the car, you will end up saying to your self: HOLY CRAP,,, ,,, Why the hell did I wait so long to do this??

I purchase my C6 ZO6 shocks from Gene or Patrick at Cultrag Performance. Good people and good prices!

C6 ZO6 shocks are 100% bolt in without ANY modifications!
NOTE! (F-45 & F-55 RPO will require BCM RPO modification with the GM TECH 2)

Here is a link to C6 ZO6 Shocks, sway bars and springs:

https://www.corvetteforum.com/forums...rformance.html



Bill