Manual Trans woes
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,474
Likes: 4
From: Tracy CA
Manual Trans woes
I'm a C4 guy for the past 12 years and finally took the jump to a C5 last week. 
I bought a 2000 Coupe with the manual trans and Z51. Bone stock. It's a beautiful car and does most things better than my 92. I picked it up in Texas and drove it back to California, so I've got plenty of miles under my belt. 
The issue is: The shifter/clutch/transmission is very challenging to operate smoothly. My 92 with the ZF tranny is much easier to operate smoothly and effectively.
I realize that the C5 has a transaxle in the back and that this necessitates a linkage based shifter. When I shift from 1st to 2nd, the engine speed drops so fast that the rpm is below where it would be in 2nd gear at that speed, so the car has a jerky motion as the engine catches up and then the throttle is applied..
The LT1 engine RPM doesn't seem to drop as fast, and the actual shift is quicker so the whole process is just a masterpiece of forward acceleration...
Any thoughts? Is this abnormal and I should be under the car looking for something broken? Does the linkage need lubrication? Is there an aftermarket solution that you all have found?
I bought a 2000 Coupe with the manual trans and Z51. Bone stock. It's a beautiful car and does most things better than my 92. I picked it up in Texas and drove it back to California, so I've got plenty of miles under my belt. The issue is: The shifter/clutch/transmission is very challenging to operate smoothly. My 92 with the ZF tranny is much easier to operate smoothly and effectively.
I realize that the C5 has a transaxle in the back and that this necessitates a linkage based shifter. When I shift from 1st to 2nd, the engine speed drops so fast that the rpm is below where it would be in 2nd gear at that speed, so the car has a jerky motion as the engine catches up and then the throttle is applied..
The LT1 engine RPM doesn't seem to drop as fast, and the actual shift is quicker so the whole process is just a masterpiece of forward acceleration...
Any thoughts? Is this abnormal and I should be under the car looking for something broken? Does the linkage need lubrication? Is there an aftermarket solution that you all have found?
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
First, congratulations and good luck with the new car 
The aftermarket shifter, with the exeption of the C6 shifter, will make it harder to shift and more notchy feeling. I would start with a transmission fluid change, which wouldn't hurt anyhow. Is the problem going from first to second the 1-4 shift gate? I am wondering if you are running into the CAGS gate movement. Is is all gears, or just 1 to 2?
The aftermarket shifter, with the exeption of the C6 shifter, will make it harder to shift and more notchy feeling. I would start with a transmission fluid change, which wouldn't hurt anyhow. Is the problem going from first to second the 1-4 shift gate? I am wondering if you are running into the CAGS gate movement. Is is all gears, or just 1 to 2?
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,474
Likes: 4
From: Tracy CA
The problem is not CAGS. I had the same thing on the 92. It's most noticible with the 1-2 shift (mostly because the gear ratios are lowest.)
As an aside: Can I unplug the CAGS connector on the trans and leave it? Or is the kit required to keep the computer happy?
On the LT1, the only purpose of the kit was to keep the wires out of the way... It had no electrical component.
As an aside: Can I unplug the CAGS connector on the trans and leave it? Or is the kit required to keep the computer happy?
On the LT1, the only purpose of the kit was to keep the wires out of the way... It had no electrical component.
Racer
Joined: Dec 2005
Posts: 407
Likes: 2
From: Mesquite, Texas
Originally Posted by mitchcole
The problem is not CAGS. I had the same thing on the 92. It's most noticible with the 1-2 shift (mostly because the gear ratios are lowest.)
As an aside: Can I unplug the CAGS connector on the trans and leave it? Or is the kit required to keep the computer happy?
On the LT1, the only purpose of the kit was to keep the wires out of the way... It had no electrical component.
As an aside: Can I unplug the CAGS connector on the trans and leave it? Or is the kit required to keep the computer happy?
On the LT1, the only purpose of the kit was to keep the wires out of the way... It had no electrical component.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
WOW! I found that the C5 MN6 tranny shift and gear ratio to be SOOO much better than the C4. What RPM's are you shifting at?? It almost sounds like your shifting too slowly or hesitating between shifts. I can go from 1st to 2nd smooth enough that it almost feels like an automatic!
Do you know if the car has any modifications??? It almost sounds like it has a light weight aluminum flywheel and it's not carrying the rotational momentum of the engine through to allow the shift to happen smoothly. If it has an aluminum fly wheel it will take some getting use to before it feels natural.
BC
Do you know if the car has any modifications??? It almost sounds like it has a light weight aluminum flywheel and it's not carrying the rotational momentum of the engine through to allow the shift to happen smoothly. If it has an aluminum fly wheel it will take some getting use to before it feels natural.
BC
Le Mans Master
Joined: Sep 2004
Posts: 6,018
Likes: 565
From: Conroe Texas
hey...another c5 noob. i myself just upgraded to a c5 from the c4 last week, drove over to austin on friday and picked up a nbm/oak 6-speed with z-51 suspension. the z-51 was a surprise after i started looking at the codes. other than fluids need to be changed, and i mean all of them, the car drives and shifts very nice. the only noise i get is a clunk once in a while if i granny shift, probably in the u-joints. no noise out of the pass seat, she hasn't even ridden in it yet. 
Instructor
Joined: Jul 2005
Posts: 206
Likes: 0
From: Cussing at my car somewhere
If it's an aftermarket shifter, I could see you having problems goin from 1st to 2nd. I bought my C5 with a short shifter already in it, and it was a PITA to get used to. I was also a manual nOOb, which I'm sure didn't help much at the time.
I still miss a 1st-2nd shift now and then. However, it might just be something you'll have to get used to. I can shift the car like an automatic feels now - I even had a co-worker ride with me for a couple miles before she realized that I was shifting the whole time.
I still miss a 1st-2nd shift now and then. However, it might just be something you'll have to get used to. I can shift the car like an automatic feels now - I even had a co-worker ride with me for a couple miles before she realized that I was shifting the whole time.
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Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Originally Posted by Sleazy Rider
hey...another c5 noob. i myself just upgraded to a c5 from the c4 last week, drove over to austin on friday and picked up a nbm/oak 6-speed with z-51 suspension. the z-51 was a surprise after i started looking at the codes. other than fluids need to be changed, and i mean all of them, the car drives and shifts very nice. the only noise i get is a clunk once in a while if i granny shift, probably in the u-joints. no noise out of the pass seat, she hasn't even ridden in it yet.
Richard
Purple Heart,,, (were not worthy) THANKS FOR SERVING!!
C5's don't really have the traditional U joints. The half shafts are CV joints with boots covering the joints. There are not any U joints or CV joints in the propeller shaft inside the torque tube either. I doubt if it's that. It does however have lots of splined shaft joints and the tolerances between all of those splined shafts all add up and cause that noise. The transmission(manual MN6/MN12) also has some almost straight cut gears that can make some noise. It pretty much normal for a C5. If you start the engine, set the hand brake, put the trans in neutral, let the clutch out and shut the key off, you will get a really good example of what I'm talking about. It's referred to as the "marbles in the can" noise. Yep ,,,its normal.
Bill C Retired Navy, E8 FTCS (SS)
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,474
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From: Tracy CA
I think it's probably me getting used to the car. I've gotten better at low speed and agressive shifts, but I have to really concentrate.
I'll change the trans fluid when the CAGS eliminator shows up. Recommendations on the fluid? Heard it's auto trans fluid in the manual...
I'd be shocked if the flywheel is aftermarket. EVERYTHING else is stock. That's a strange place to start making mods.
I'll change the trans fluid when the CAGS eliminator shows up. Recommendations on the fluid? Heard it's auto trans fluid in the manual...
I'd be shocked if the flywheel is aftermarket. EVERYTHING else is stock. That's a strange place to start making mods.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Yep!! Don't get real fancy with the fluid. i used Mobile 1 Synthetic ATF and it worked VERY well. My MN6 and My MN12 Manual trans shift feel improver dramatically!!
It is a very good up-grade!
Bill C
It is a very good up-grade!
Bill C
Pro
Joined: Mar 2002
Posts: 732
Likes: 138
From: Allen (DFW) Texas
I'd bet it's mostly just the differences in the cars. I just moved from a 96 LT4 to an 02 Z06 after four years of autocrossing the 96 and find the Z06 shifts to be very "notchy" compared to the smoothness of the ZF in the 96. I'm sure this is due to the linkage, as you noted. The engine responds differently as well, enough to make speed matching very different than the 96 which also sounds like what you're experiencing - probably the difference between the crispness of drive-by-wire versus the "slop" of the cable system on the 96. For me at least it's just been a matter of getting used to the difference in "feel" between the two.
Burning Brakes
Joined: Nov 2004
Posts: 988
Likes: 4
From: Livermore CA
Sounds to me like your tranny has been filled with traditional gear oil 75-80 , which won't hurt it but it will make shifting sluggish. I filled my manual MN12 with Redline DT4 ATF and thought it poured thicker than regular ATF and sure enough my transmission became sluggish to shift. I drained the Redline and refilled with Mobil 1 ATF and it shifted much better. I'm in Livermore so we're only about a half hour apart, PM or e-mail me if you need any help under your car.
Drifting
Joined: Sep 2005
Posts: 1,788
Likes: 2
From: Tallahassee FL
Heck, I've always felt that I am not really all that good at shifting gears in a manual transmission, and I've had several cars over the years to practice on. Just an acquired technique, I guess. But with my '02 Z, I found that I get the smoothest shifts if I do it right around 3K to 3.5K rpm. Sounds like you are winding it up a bit for just street driving, but it just feels better shifting at that point to me. Heck, gives you a good excuse to take it out for a spin so you can practice your shifting skills....... 
Instructor
Joined: Oct 2005
Posts: 172
Likes: 0
From: Atwater Ca
I have the same exact problem your talking about. I have a Kirban shifter and a aluminum flywheel though. If you do the trans fluid thing and it works, could you pm me. I'd appreciate it. I thought that was just how the car was.
Originally Posted by mitchcole
I'm a C4 guy for the past 12 years and finally took the jump to a C5 last week. I bought a 2000 Coupe with the manual trans and Z51. Bone stock. It's a beautiful car and does most things better than my 92. I picked it up in Texas and drove it back to California, so I've got plenty of miles under my belt.
The issue is: The shifter/clutch/transmission is very challenging to operate smoothly. My 92 with the ZF tranny is much easier to operate smoothly and effectively.
I realize that the C5 has a transaxle in the back and that this necessitates a linkage based shifter. When I shift from 1st to 2nd, the engine speed drops so fast that the rpm is below where it would be in 2nd gear at that speed, so the car has a jerky motion as the engine catches up and then the throttle is applied..
The LT1 engine RPM doesn't seem to drop as fast, and the actual shift is quicker so the whole process is just a masterpiece of forward acceleration...
Any thoughts? Is this abnormal and I should be under the car looking for something broken? Does the linkage need lubrication? Is there an aftermarket solution that you all have found?
I bought a 2000 Coupe with the manual trans and Z51. Bone stock. It's a beautiful car and does most things better than my 92. I picked it up in Texas and drove it back to California, so I've got plenty of miles under my belt. The issue is: The shifter/clutch/transmission is very challenging to operate smoothly. My 92 with the ZF tranny is much easier to operate smoothly and effectively.
I realize that the C5 has a transaxle in the back and that this necessitates a linkage based shifter. When I shift from 1st to 2nd, the engine speed drops so fast that the rpm is below where it would be in 2nd gear at that speed, so the car has a jerky motion as the engine catches up and then the throttle is applied..
The LT1 engine RPM doesn't seem to drop as fast, and the actual shift is quicker so the whole process is just a masterpiece of forward acceleration...
Any thoughts? Is this abnormal and I should be under the car looking for something broken? Does the linkage need lubrication? Is there an aftermarket solution that you all have found?
Thread Starter
Drifting
Joined: Dec 2002
Posts: 1,474
Likes: 4
From: Tracy CA
Changed the trans fluid. Someone has got to make a pump that doesn't fall apart. That Napa unit was a P.O.S.
The trans fluid was red - so that's a no go on the gear oil theory.
I'll take it for a ride tomorrow.
The trans fluid was red - so that's a no go on the gear oil theory.
I'll take it for a ride tomorrow.