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xfactor
07-22-2009, 07:22 PM
First, let me make a statement. I have driven manual transmissions all my life, first a Honda, then a 5.0LX Mustang, a Toyota truck, a TR-6, a M Roadster, and now my GXP. So, I am not Dale Earnhardt but I am not Mr. Bean either. Here's the issue with as much detail as I can offer.

I began to notice that I had difficultly going to 2nd and a little difficulty going into 3rd. It was about halfway through the shift and felt like a catch but not a grind. It was not consistent and I didn't have the issue all the time. I first thought it was me since it had been about 6 months since I drove the M Roadster. Then I started to think it was the skip shift solenoid not retracting all the way (I am guessing that is how it worked) but never really hung my hat on this one. Then I started to think it was the clutch pressure plate, think I wore it out but couldn't believe this as I don't ride the clutch and it was not consistent. One thing I noticed is that when it is doing it if I push the clutch in while driving 30+ mph and put it in a low gear, namely 1st, but not let the clutch out I could feel some engagement.

I start trying to see when it happened and what was similar about the occurrences. I have noticed that it is much worse when the temperature is below 50 F until the car heats up. One thought I had is that the transmission is low on fluid but it is sealed and there are no visible signs of leakage. I thought this thinking that if it was low after setting the fluid would be on the bottom and not on all the gears and since it was cooler it would be thick and have to heat up to get on all the gears. This didn't make since at that would mean that the gear oil is the consistency of butter, and I don't think it is.

I recently read the thread on the clutch master cylinder. This got me thinking, maybe that is what it is. If the cylinder was bad and had blow by it could very well do this. When the fluid is cold and thicker, then it would have to press harder and the blow by would increase. I checked the level of fluid in the master cylinder (I am assuming that the hydraulic clutch uses the same reservoir) and it didn't appear low. It was not below the bottom of the vertical slot in the reservoir. One thing I did notice is that the fluid is almost the color and clarity of tea. I noticed that this morning it was as smooth as glass, this evening was the same going to the dry cleaners, but going home I could feel it. The last week has been pretty good since the temp has been at least 60 in the morning and high 80's in the evening.

So a few questions for you expert types:
1. Is the master cylinder reservoir used for the hydraulic clutch fluid?
2. Is the color and clarity right for the fluid?
3. What the hell is up with my clutch?

I am going to schedule a visit with the Pontiac dealer but they more than likely haven't seen one and haven't have manual transmission experience in quite a few years so I would like to have my shit together before they try to suggest some crazy stuff.

Thank you all for your input.

X

xfactor
07-24-2009, 09:59 PM
Okay, 66 of you have viewed this but none have commented. I know there are a lot of you that know more about this than I do. The car is going for some warranty work on Monday and I would love to have your input prior to taking it in. I will be going to the PNW:Picnic in the Park tomorrow and will talk with some of you there but any suggestion from those of you view would be greatly appreciated.

Thanks,
X

wreckwriter
07-25-2009, 05:20 AM
Sorry, I know zip about manual trans.

99-LS1-SS
07-25-2009, 05:33 AM
Mine is sometimes notchy when it's cold too. Maybe not to the degree that you are talking about though. My clutch kept slipping and smelling bad. I totally flushed the fluid out and put fresh in and it seemed to cure that part of the issue. It didn't address the notchy feeling though. If you fluid is anything other than clear very pale tan then you might need to flush it.

chuckwi11
07-28-2009, 02:24 PM
I read on here about checking the fluid color and much to my chagrin when I checked mine today it looked like maple syrup. I haven't driven the car hard in the first 1500 miles but I have driven it fast.

Not sure if this has been posted before but there is a really good post over on the Corvette forums by a guy named Ranger. He has a seven minute video on root causes of clutch problems and how to resolve them. The video shows in detail how to change the fluid... not sure if I am allowed to post the link since it is in another forum... after watching the video I don't feel so doomed and the procedure is much easier than I imagined to get the contaminated fluid out.

What is the BEST fluid to run in the GXP? I realize DOT 3 but are they all pretty much the same or are there better ones?

-Ray-
07-29-2009, 05:03 AM
Go ahead and post the link.

JoshHefnerX
07-29-2009, 10:52 AM
Did you get your car into the dealer, and have they found anything?

I did notice on my last 'newer' car w/ a manual that the shifting did get much notchier when the fluid was cold and smoothed out when warm.

If the clutch MS or slave was going bad you would probably notice shifting problems in most or all gears.

Josh

xfactor
07-29-2009, 08:03 PM
I have been travelling and am in Texas. My wife dropped the car off at the dealer on Monday with my hand written laundry list of items I wanted them to address, the main one being this issue. The dealer also is a Chevy dealer so I feel more comfortable since they service Corvettes and should know a little about the xmsn. The mechanic said that the new xmsn has manual gates that they must go through which may be what I was feeling but they were going to check into it. He said he had been reading about this on the web as well. She checked on it today and they said they are waiting on parts (they didn't say which parts, they were replacing the 3rd brake light and sun visor clip) and would have the car ready by Friday, which happens to be the day I return. I will update as soon as I know more.

X

xfactor
08-01-2009, 09:32 AM
No new news. I went by the dealer and talked with him. They are waiting on a piece for the sunroof so I told them to keep it until it comes in. He has a few ideas on the transmission issues but wants to talk to GM to see if anyone else has had the same issue. He believes that there may be burs on the fingers that the shifter pushes causing the problem. I will let you know more as I learn.

Mr. Bueno
10-17-2009, 09:15 PM
keep us informed xfactor. It has been over 2 months.

Mr. B

RWD-V8
01-27-2011, 01:20 PM
Did you ever get this diagnosed? I have the same problem with my 1>2 and 2>3 shifts when cold.

AVIDMOTION
02-18-2011, 02:47 AM
update please