98 MN6 goes into any gear, but car doesn't move. Help?!
05-29-2017, 12:48 PM
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98 MN6 goes into any gear, but car doesn't move. Help?!
Happy Memorial Day! I have been trying to diagnose an issue with my 98 c5 (full bolt ons 500+Flywheel HP).
My new problem is that now, no matter what gear I put the shifter into 1,2,3,4,5,6th, R, the car will not move. It will shift into gear without any issue but the motor just revs and no movement. The clutch pedal feels like normal and you must press in to start the car, car will not start without clutch pedal pushed in. I know I now have no choice but to drop the entire driveline and look, but wanted to know from you guys what the issue might be? Also, while I’m in there, what else would you suggest replacing. I did have an LS7 Clutch/flywheel/pressure plate/ master/slave/throw-out bearing replaced about 4 years ago when we did the mods.
Below is the original post of what the problem was that I was experiencing before the car wouldn't move.
It is a 98 c5 full bolt ons (75,000 miles). I do have an aftermarket ls7 clutch installed a few years back. The problem is there is a very loud vibration coming from the car around 2500-4000RPM. It is coming from under the dashboard (Behind motor) and right under the shifter (Shifter vibrates on its own). What is confusing to me is that if I shift nice and cruise around, you won't hear anything. I can also shift into all gears without issue. I have also started to experience the "bolts in a can" sound, but this only happened once, and then went away when I let the car sit overnight (normal from what I've read?). I have the vibration sound coming from the back of the motor even if the car is running but not in gear. If I rev the motor to (2500-4500RPM), you can hear and feel the vibration but not as bad as though if it were in gear. Since I am hearing the sound from the behind the motor and even if the car is in gear or not, does this sound like TT bushings? Anything I can on my own check before I find somewhere to bring it into?
To me it feels like a washing machine that is unbalanced and when it is on spin cycle the whole machine shakes around.
What is even stranger being that if I go past 4500RPM, the vibrations become very light and almost disappear.
Do Torque tubes become unbalanced over time?
Any help or direction would be great!
Thanks!
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Old 05-16-2017, 11:48 AM #2
jarnold
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Default Vibration
It could be the shifter rubber mounts. I would pull the trim out and see. That would be hopefully the cheapest and best thing. If they are cracked or worn buy the Zips Urethane kit. Did this on mine to blue print the stocker but I did that to try to fix the hard shift to reverse. Highly doubt this is the problem however. Mine was not vibrating like yours.
If the clutch is working OK then it could be the drive shaft coupling. That is what is sounds like to me. Or it might be the Throw out bearing. You would feel that engaging the clutch. Both basically would be the same labor as the Clutch. If this is either of these then do the clutch and slave cylinder as well. 75K I would. Did a Clutch recently and it was 650.00 in labor and do the same LS7 clutch. I however found out that the Luk Pro Gold type Clutch is the same and for almost half and adding the GM Slave/ Throw-out bearing (Did they replace that earlier) the total was about 450.00 for those parts.
My new problem is that now, no matter what gear I put the shifter into 1,2,3,4,5,6th, R, the car will not move. It will shift into gear without any issue but the motor just revs and no movement. The clutch pedal feels like normal and you must press in to start the car, car will not start without clutch pedal pushed in. I know I now have no choice but to drop the entire driveline and look, but wanted to know from you guys what the issue might be? Also, while I’m in there, what else would you suggest replacing. I did have an LS7 Clutch/flywheel/pressure plate/ master/slave/throw-out bearing replaced about 4 years ago when we did the mods.
Below is the original post of what the problem was that I was experiencing before the car wouldn't move.
It is a 98 c5 full bolt ons (75,000 miles). I do have an aftermarket ls7 clutch installed a few years back. The problem is there is a very loud vibration coming from the car around 2500-4000RPM. It is coming from under the dashboard (Behind motor) and right under the shifter (Shifter vibrates on its own). What is confusing to me is that if I shift nice and cruise around, you won't hear anything. I can also shift into all gears without issue. I have also started to experience the "bolts in a can" sound, but this only happened once, and then went away when I let the car sit overnight (normal from what I've read?). I have the vibration sound coming from the back of the motor even if the car is running but not in gear. If I rev the motor to (2500-4500RPM), you can hear and feel the vibration but not as bad as though if it were in gear. Since I am hearing the sound from the behind the motor and even if the car is in gear or not, does this sound like TT bushings? Anything I can on my own check before I find somewhere to bring it into?
To me it feels like a washing machine that is unbalanced and when it is on spin cycle the whole machine shakes around.
What is even stranger being that if I go past 4500RPM, the vibrations become very light and almost disappear.
Do Torque tubes become unbalanced over time?
Any help or direction would be great!
Thanks!
97Z06 is online now Report Post Edit/Delete Message Reply With Quote Multi-Quote This Message Quick reply to this message
Old 05-16-2017, 11:48 AM #2
jarnold
CF Member
jarnold's Avatar
Member Since: Apr 2009
Posts: 90
Thanks: 1
Thanked 1 Time in 1 Post
Default Vibration
It could be the shifter rubber mounts. I would pull the trim out and see. That would be hopefully the cheapest and best thing. If they are cracked or worn buy the Zips Urethane kit. Did this on mine to blue print the stocker but I did that to try to fix the hard shift to reverse. Highly doubt this is the problem however. Mine was not vibrating like yours.
If the clutch is working OK then it could be the drive shaft coupling. That is what is sounds like to me. Or it might be the Throw out bearing. You would feel that engaging the clutch. Both basically would be the same labor as the Clutch. If this is either of these then do the clutch and slave cylinder as well. 75K I would. Did a Clutch recently and it was 650.00 in labor and do the same LS7 clutch. I however found out that the Luk Pro Gold type Clutch is the same and for almost half and adding the GM Slave/ Throw-out bearing (Did they replace that earlier) the total was about 450.00 for those parts.
