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Greetings,
I have a problem with my 99 Pontiac Sunfire 2.4L Manual Trans. and I hope someone can take the time to read this and help out! I am new here by the way.
It started when the clutch pedal got to the grabbing point, a grinding noise was coming from to left front end, the car won’t move an inch! I put in in 2nd gear, 3rd… it won’t move and the grinding continues. I noticed when I press on the clutch all the way down the grinding noise goes away. When I let it off as if I were to move with 1st gear engaged, the grinding comes back on and, again, the car won’t move. I first thought it was one of the clutch components that was shot so I decided to pull the transmission and I did not see anything wrong with the clutch assembly. I decided, however, to replace the clutch as I was not sure if the Release Bearing/Slave Cylinder assembly failed. I also put on a new flywheel. So new LuK Kit installed, bled the clutch and put everything back together, still same issue. Is it the Transmission? Well, I went to the junkYard and picked up one, they told me it’s in working condition. I installed it, same problem. Is it faulty? What am I missing here? I would also like to add that you can shift to 1st gear, without pressing on the clutch, it grinds a little bit, and I just wanted to try that for further diagnosis and may be an important piece of information that you may need to know.I look forward to any response on this issue, Thank you very much!
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I took 2 short videos today:
Video1: The grinding starts from 03sec while it’s in Neutral. I put it in gear and the grinding completely stops when I press on the clutch:
https://www.youtube.com/watch?v=BbKaoUssvIIVideo2: Under the hood I am slightly pushing the shifter and you can hear the gears or synchros grinding.
https://www.youtube.com/watch?v=CEZzGQQcRE8[quote=”Marigh” post=80779][quote=”Raistian77″ post=80736]Okay, looked it up and yep you have the slave cylinder that bolts up inside the housing, like Ford did for a long time. That slave cylinder is jammed, seen it before. Putting it inside abuses the hell out of them, heat/cold cycles and all the dust just does a number on them. They get jammed up and feel fine pedal wise but wont let the trans fully disengage. The ones Ford used were notorious for leaking so at the shop we replace all internal slave cylinders when we do clutch work.
Try a new slave cylinder before spending any more money, that thing is the true weak link in that system and it’s jamming would explain all your symptoms. The reason it gets quiet when you press on the pedal is it can still move forward just fine but not all the way back. The reason the pedal feels fine is the same reason disc brakes dont feel weird after the pads have worn awhile, they self-adjust. I’ll bet your fluid is a tad on the low side, because a bit more of it is trapped in the slave cylinder.[/quote]
Ok, so I got all the fluid out of the Release Bearing by doing this: Valve open, clutch pedal is pushed, fluid out, valve is closed, pedal is released, kind of reverse of bleeding. I repeated the same process till fluid stopped flowing out. The Pedal was completely loose and down to the floor. By now the Release Bearing should go all the way back. I turned the engine on and grinding did not get any quieter. I put the fluid back in and bled the clutch system, again, the grinding stops completely when I press on the pedal. When I removed the Transmission the 2nd time, the Release Bearing was disengaged completely, and it should especially if the clutch pedal is not pushed and the hydraulic line is disconnected.[/quote]
It is hard to tell if it is all the way back by looking at it. I have seen them jam, just a 1/4 inch forward is enough to push on the clutch fingers and slightly disengage the clutch disc from the pressure plate. If it were mine I would pop the trans back off, pull the slave cylinder and compare it to a new one and see if there is a difference.
[quote=”Raistian77″ post=80790][quote=”Marigh” post=80779][quote=”Raistian77″ post=80736]Okay, looked it up and yep you have the slave cylinder that bolts up inside the housing, like Ford did for a long time. That slave cylinder is jammed, seen it before. Putting it inside abuses the hell out of them, heat/cold cycles and all the dust just does a number on them. They get jammed up and feel fine pedal wise but wont let the trans fully disengage. The ones Ford used were notorious for leaking so at the shop we replace all internal slave cylinders when we do clutch work.
Try a new slave cylinder before spending any more money, that thing is the true weak link in that system and it’s jamming would explain all your symptoms. The reason it gets quiet when you press on the pedal is it can still move forward just fine but not all the way back. The reason the pedal feels fine is the same reason disc brakes dont feel weird after the pads have worn awhile, they self-adjust. I’ll bet your fluid is a tad on the low side, because a bit more of it is trapped in the slave cylinder.[/quote]
Ok, so I got all the fluid out of the Release Bearing by doing this: Valve open, clutch pedal is pushed, fluid out, valve is closed, pedal is released, kind of reverse of bleeding. I repeated the same process till fluid stopped flowing out. The Pedal was completely loose and down to the floor. By now the Release Bearing should go all the way back. I turned the engine on and grinding did not get any quieter. I put the fluid back in and bled the clutch system, again, the grinding stops completely when I press on the pedal. When I removed the Transmission the 2nd time, the Release Bearing was disengaged completely, and it should especially if the clutch pedal is not pushed and the hydraulic line is disconnected.[/quote]
It is hard to tell if it is all the way back by looking at it. I have seen them jam, just a 1/4 inch forward is enough to push on the clutch fingers and slightly disengage the clutch disc from the pressure plate. If it were mine I would pop the trans back off, pull the slave cylinder and compare it to a new one and see if there is a difference.[/quote]
This is a brand new Release Bearing we’re talking about, it came with LuK Clutch Kit. When I removed the Transmission the 2nd time it looked fully disengaged just like how it came in the box, and I was having the exact same issue even before I replaced the clutch. Maybe I should remove the Transmission and put everything back together excluding the Release Bearing, if it is not there and if it is what’s causing all this, I should not hear any grinding and I should not be able to change to any gear from Neutral, right?
True, but if you are going to pull it apart, I would pull the old slave cylinder and run it over to the local parts store and set it side by side with a new one and see if there is any difference in release bearing height.
Similar to your issue
http://www.thetruckstop.us/forum/showthread.php?8985-Internal-clutch-slave-cylinderOther issues with concentric slave cylinders
I’m pretty sure your truck has a concentric slave cylinder, which fits around the input shaft of the transmission. I’ve never heard anything good about them, but most of the manufacturers have gone to them for weight and cost savings.
They live in a horrible environment with heat and abrasive dust. The piston has a large diameter to length ratio, which makes it easy for it to get cocked in the bore. When that happens, the pedal will come up, but the clutch won’t be engaged. In some installations, it’s a long arduous procedure to get the air out of the system.
Some service manuals call for it to be replaced whenever the transmission is removed, even if it’s not yet causing any problems.
It’s truly a design from hell.
[quote=”Raistian77″ post=80903]True, but if you are going to pull it apart, I would pull the old slave cylinder and run it over to the local parts store and set it side by side with a new one and see if there is any difference in release bearing height.
Similar to your issue
http://www.thetruckstop.us/forum/showthread.php?8985-Internal-clutch-slave-cylinderOther issues with concentric slave cylinders
I’m pretty sure your truck has a concentric slave cylinder, which fits around the input shaft of the transmission. I’ve never heard anything good about them, but most of the manufacturers have gone to them for weight and cost savings.
They live in a horrible environment with heat and abrasive dust. The piston has a large diameter to length ratio, which makes it easy for it to get cocked in the bore. When that happens, the pedal will come up, but the clutch won’t be engaged. In some installations, it’s a long arduous procedure to get the air out of the system.
Some service manuals call for it to be replaced whenever the transmission is removed, even if it’s not yet causing any problems.
It’s truly a design from hell.
[/quote]
When I removed the old one, it actually looked fine and the car has 148k miles, so you might think over time, as mentioned in the article, dust, heat, etc will cause them to fail, I agree with that to certain extent. In my case, at 148K, it still functioned as it’s supposed to. I first thought it’s a crappy design but if you think about it, they kind of bypassed the Slave Cylinder, which I prefer over having external Slave Cylinder AND Throwout Bearing in the Bell Housing, but that’s me.
Ok, so I compared it (it’s still new) to another Brand new one and they both looked identical.
Well, that is all there really is.
The likelihood of two identical bad transmission is almost nil. Since changing the trans made no difference to the problem it is unlikely that it is a trans problem. You changed out the clutch components with no change so it is unlikely there is a problem with the clutch. The only thing that seems to have remained since the original issue is the axles, slave cylinder and linkages.
Even if the axles were bad they would not cause the grinding when shifting problem.
You can take the linkages off and you still have the same issue so it cant be them.
You tried it with the line removed so the master can not be causing the problem.
Only thing left to try is the slave cylinder (since it sounds like you have reused the original one) and concentric slaves have a long history of being nothing but problems (there is a reason everyone went back to externals).
One way to rule out the trans is to pull it and manually work it. Slap your axles in the trans when it is out and turn the input shaft by hand and run through the gears. Watch the axles and see if they turn properly.
Normally I would recommend checking the pilot bearing, but according to the parts store websites and Alldate yours did not come with one.
Something is causing your clutch to not disengage all the way, basically it is like you are pushing the pedal about halfway down, enough to be able to shift it with your foot off the clutch.
[quote=”Raistian77″ post=80933]Well, that is all there really is.
The likelihood of two identical bad transmission is almost nil. Since changing the trans made no difference to the problem it is unlikely that it is a trans problem. You changed out the clutch components with no change so it is unlikely there is a problem with the clutch. The only thing that seems to have remained since the original issue is the axles, slave cylinder and linkages.
Even if the axles were bad they would not cause the grinding when shifting problem.
You can take the linkages off and you still have the same issue so it cant be them.
You tried it with the line removed so the master can not be causing the problem.
Only thing left to try is the slave cylinder (since it sounds like you have reused the original one) and concentric slaves have a long history of being nothing but problems (there is a reason everyone went back to externals).
One way to rule out the trans is to pull it and manually work it. Slap your axles in the trans when it is out and turn the input shaft by hand and run through the gears. Watch the axles and see if they turn properly.
Normally I would recommend checking the pilot bearing, but according to the parts store websites and Alldate yours did not come with one.[/quote]
Thank you for taking the time to respond, I really appreciate it!
Yes, exactly, I was going to list the steps I took to diagnose the problem and there you listed them. If the axles or splines were bad, I should not be able to shift without pressing on the clutch pedal. Also, it should not grind when it’s in Neutral. I can remove the axles from the transmission and turn the car on while it’s on the lift and the grinding is still present. I inspected all splines, they’re good. So I guess axles are ruled out.
No, I did not reuse the old Release Bearing, like you said, it could be jammed and I can’t visually tell, but it looked like the new one I installed, not cosmetically but it did not have any signs of failure compared to the new one, I still disposed of it and slapped in the new one that came with LuK Clutch kit. I can take the chance of putting everything back together without it and see if I will experience the same problem. It’s not the best way to diagnose but, that’s all that’s left I think. Release Bearing or the Transmission. I will check the Transmission as you described and go from there.
No, there is not a Pilot Bearing to check and when I removed the Flywheel, everything looked dry, there is no leakage anywhere.[quote=”Raistian77″ post=80933]
One way to rule out the trans is to pull it and manually work it. Slap your axles in the trans when it is out and turn the input shaft by hand and run through the gears. Watch the axles and see if they turn properly.[/quote]Back.
I took the Trans. out, installed the both axle shafts in, turned the input shaft by hand and I noticed that the axles were turning in Neutral. Also, when I put it in gear, I can still turn the input shaft forward and backward, which makes me wonder if I am engaging the gears correctly. Check out the pictures.Before I pulled the Transmission, when the car is off and if you engage 1st gear, the car won’t roll forward. On R, it won’t roll back, so I think the gears are ok, something else is messed up, synchros, etc. or the gears do not engage when the engine is on.
If I remember right that should be reverse you have it in.
Due to the differential design, the axles may be funky as you turn the input shaft. What you are looking for is the transmission will go into all gears and turn the axle (one might stay still that is how a differential works) in the proper direction. Make sure you turn the input like the engine would turn it, the gears are helical cut and are designed to spin better in that direction.
[quote=”Raistian77″ post=81343]If I remember right that should be reverse you have it in.
Due to the differential design, the axles may be funky as you turn the input shaft. What you are looking for is the transmission will go into all gears and turn the axle (one might stay still that is how a differential works) in the proper direction. Make sure you turn the input like the engine would turn it, the gears are helical cut and are designed to spin better in that direction.[/quote]
Update:
I did that and the gears still spun in both directions, and as I’ve mentioned I checked everything else. So, I removed the Trans. and returned it, then went and got one from a junkyard, installed it then the car finally moved, no more grinding!!!
2 Trans. with the EXACT same failure symptoms, go figure!Thank you very much for your time and help, very much appreciated.
I’m happy to know that you “got-er-dun”. I don’t know where all of your patience comes from but I bet you can do that job in record time now.
It’s unusual to see the same failure in two transmissions especially in your scenario but If you work on cars long enough you will find out that impossible things are indeed possible.
To me the transmission had to be the problem although others had legitimate possibilities also.
CHEERS!
[quote=”wysetech” post=82359]I’m happy to know that you “got-er-dun”. I don’t know where all of your patience comes from but I bet you can do that job in record time now.
It’s unusual to see the same failure in two transmissions especially in your scenario but If you work on cars long enough you will find out that impossible things are indeed possible.
To me the transmission had to be the problem although others had legitimate possibilities also.
CHEERS![/quote]
Thanks man! It was a tricky one because the guy I bought it from, at a junkyard, said that it was in working condition. So I ruled it out first, and like yous said, other possibilities were legitimate, but they were all checked and proved to be in good working conditions, and that’s when I got lost. I had to drive to PA to pick it up, I live in NY. Fortunately it was only 2 hours drive. These 2.4L are hard to find!! The Trans. I picked up has 90k miles and cost $350 so I went for it after I returned the other broken one. I used GM Acdelco Synchromesh fluid, what a great product they made!
Again, thank you!! CHEERS!
[quote=”college man” post=82356]Glad you worked it out.Thanks for the update and the fix.[/quote]
🙂
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