[LedHed]

I recently bought a manual 2007 GXP with 27k miles.

There are a few questions I had and maybe, some other experiences will help.

It is taking me some real time to perfect this clutch + transmission, compared to FBodies. At first I am either goosing it, or lunging it for the first week. Finally, I realize there is no reason in normal driving to push the clutch to the floor (unless you are parked and going into reverse). Not to mention, the first 1/3 of the stroke (from the floor) is totally useless in normal driving. However, that is only the start of the quirks of learning this particular car.

For some reason, 4th gear in this car, will occasionally miss if you don't slightly tend to the right. If you want to just flick gears with a few fingers, you better know this, for this vehicle anyway. Also, reverse has about a 50% success rate of going in on the first try, when first cranked and the oil is cold. I will try once and then if it won't go, let the clutch out and push it back in again, always goes in at that point.

What I want to know, is how can you improve these slight issues, on an otherwise great car? I was considering replacing the transmission and differential fluids, possibly flush + replace the clutch fluid too. If I am going to do all of that, I might as well flush the coolant too. I was thinking MT-90 for the trans. Any thoughts on other fluids mentioned, that would improve the experience?

Also, how normal are these for a manual GXP?

Thanks in advance,
Led

 

[kgschlosser]

Reverse and 1st gear share the same syncro. so if you push the clutch in and move the shifter into 1st then take it out of 1st and go into reverse it will go into gear.

The thing you are having a hard time with is not the clutch, it is the cars computer coupled with the dual mass flywheel. The ECM causes rev hang when you shift, so no "flicking" into gears as the syncros won't be aligned properly because of the rev hang. The ECM also take care of stepping on the accelerator for you if the RPMs drop too low.

As far as the placement of the gears and how you have to move the shifter handle you can try changing the shifter out for a short throw. This may help. You also said you bought the vehicle used so who knows how the previous owner drove the vehicle. Doing things like keeping a hand resting on the shifter when not shifting gears causes wear to the shifter assembly and this could be what you are encountering.


it's a learning curve to say the least. For someone that knows how to drive a real manual transmission vehicle the nannies in the solstice tend to get in the way.

 

[kentlarue]

I recently bought a manual 2007 GXP with 27k miles.

There are a few questions I had and maybe, some other experiences will help.

It is taking me some real time to perfect this clutch + transmission, compared to FBodies. At first I am either goosing it, or lunging it for the first week. Finally, I realize there is no reason in normal driving to push the clutch to the floor (unless you are parked and going into reverse). Not to mention, the first 1/3 of the stroke (from the floor) is totally useless in normal driving. However, that is only the start of the quirks of learning this particular car.

For some reason, 4th gear in this car, will occasionally miss if you don't slightly tend to the right. If you want to just flick gears with a few fingers, you better know this, for this vehicle anyway. Also, reverse has about a 50% success rate of going in on the first try, when first cranked and the oil is cold. I will try once and then if it won't go, let the clutch out and push it back in again, always goes in at that point.

What I want to know, is how can you improve these slight issues, on an otherwise great car? I was considering replacing the transmission and differential fluids, possibly flush + replace the clutch fluid too. If I am going to do all of that, I might as well flush the coolant too. I was thinking MT-90 for the trans. Any thoughts on other fluids mentioned, that would improve the experience?

Also, how normal are these for a manual GXP?

Thanks in advance,
Led

View attachment 123082

I'd say the trans can be a little notchy at times but if you stay on top of it it'll cooperate

 

[LedHed]

Reverse and 1st gear share the same syncro. so if you push the clutch in and move the shifter into 1st then take it out of 1st and go into reverse it will go into gear.

The thing you are having a hard time with is not the clutch, it is the cars computer coupled with the dual mass flywheel. The ECM causes rev hang when you shift, so no "flicking" into gears as the syncros won't be aligned properly because of the rev hang. The ECM also take care of stepping on the accelerator for you if the RPMs drop too low.

As far as the placement of the gears and how you have to move the shifter handle you can try changing the shifter out for a short throw. This may help. You also said you bought the vehicle used so who knows how the previous owner drove the vehicle. Doing things like keeping a hand resting on the shifter when not shifting gears causes wear to the shifter assembly and this could be what you are encountering.


it's a learning curve to say the least. For someone that knows how to drive a real manual transmission vehicle the nannies in the solstice tend to get in the way.

Thanks for some insight into what is going on here, you are probably right about the ECM + flywheel being the real issue on learning this car. I am wondering if another symptom I mention below, is related to them, or is this something else?

Sometimes, when I am taking off and I want to go really slow (like a parking lot full of cars), the car seems to shutter/shake for the first few yards (normally, right as the clutch is released). I had my brother in the car (who owns a Cobra and a 2nd Gen Formula), he thought the clutch was chattering (due to the clutch springs). Now I am wondering if this is a symptom of the "nannies" that the car uses. I have stalled it out once (on the first test drive) and that is totally different from this. The car doesn't try to die, it just has a slight shake. I am giving it around 1000-1200 RPM to get her moving, surely that is enough to take off smoothly!

I love the car and I'd like to get a tune from Kappa Customs, but until the car feels solid all around, I won't even consider it.

I'm not against replacing hardware (like the clutch) if it's needed, I just figured fluids were the easiest path to take, which might alleviate some of this.

Thanks again!

 

[kgschlosser]

some of what you may be feeling could be caused by the dual mass flywheel. These cars are designed in an interesting manner. The dual mass flywheel performs quite a bit of the duties of a harmonic balancer and you could be feeling a small amount of surging when the cylinders fire. This would give the feeling that the clutch is chattering.


Is it the same kind of a feeling you would get if you are in too low a gear and the engine shutters because of it? Have you tried to be in second gear when rolling like that instead of being in 1st? if not give that a shot and see if the "chatter" is still there.

I would not be surprised if the clutch is chatter driving at that slow a speed without stepping on the accelerator at all. Reason why is the clutch in the Solstice does not have any dampening springs on it so there is no give to the clutch. The flywheel is made in 2 pieces where one piece is connected to the engine and the other is what the clutch plate rides against. The 2 pieces are attached to each other via large springs. This is a good design to stop vibrations from the engine getting to the transmission and helps smoothing out the transition when releasing the clutch . Once the clutch is engaged it offers little no to dampening of things like clutch chatter. All clutches chatter to some extent., the design on the clutch is what limits how much of it you feel.

I think you need to drive the car around for a while and get used to the clutch. Go and find some steep ass hills and get used to what the car feels like when you take off from a stop on a hill.


I am not sure why GM went with the design they did with the clutch. The rest of the car screams sports car and roadster but the clutch has nothing to offer the driver in terms of a sports car feel. They decoupled the driver from the vehicle too much and lost a portion of the sports car feel when they did that.

When my clutch burns up I will be replacing it with a dual plate clutch masters clutch and putting a single mass flywheel in. An attempt to get back some of what was lost with the OE design.