Help! Possible serious transmission issue!
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Help! Possible serious transmission issue! A few weeks ago I took the car to the dealer for noises in the steering system. They diagnosed a few loose bolts but along the way, they say I have a weak transmission mount (auto tranny). I tell them to go ahead and replace it.
Now I get on it for the first time since, and notice a lot of popping noises (sounds like it is coming from the rear). This is the first time EVER that I experience this. Drivetrain acts normal when I drive normal. Any ideas? Please help!! Thanks!!!!
Now I get on it for the first time since, and notice a lot of popping noises (sounds like it is coming from the rear). This is the first time EVER that I experience this. Drivetrain acts normal when I drive normal. Any ideas? Please help!! Thanks!!!!
Staging Lane
Joined: Nov 2007
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well is it coming from the trans tunnel area??...I know that the newer rubber trans mounts are softer then the original stock ones. Its a softer rubber over all and has more give...This is why I went to a energy suspension trans mount....has just enough cushion but its fairly sturdy so you wont get the trans hopping up and hitting the tunnel. I have been extremely happy with it.....if you decide to get a ES mount make sure you grind down the rubber bumps on it flat( when you get it you will understand) and do not use the pre load plate that comes with it. It can change your shaft angle for the worse....let e know if you need help installing if you get it.....it may not be the problem but it sure sounds like it
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Thanks TransAm11973, sounds pretty believable since I know for sure, not only did this not happen before they changed the transmission mount, but is isn't NORMAL! And yes it sounds like it is coming anywhere from the transmission tunnel to the rear axle (which was previously rebuilt).
I just looked underneath the car and did not notice any evidence of any parts colliding with each other (driveshaft is what I was mostly looking at since I have a driveshaft loop). Where else should I look?
Funny, I don't experience this if I punch it from a complete stop (the tires still spin pretty good). I also don't experience if I am cruising around 40-50 and punch it (downshift into second).
So in actuality, my stock mount they called "weak" was stronger than the new one I have now? I purposely went to the dealer thinking I was going to get exactly what was originally on the car.
I just looked underneath the car and did not notice any evidence of any parts colliding with each other (driveshaft is what I was mostly looking at since I have a driveshaft loop). Where else should I look?
Funny, I don't experience this if I punch it from a complete stop (the tires still spin pretty good). I also don't experience if I am cruising around 40-50 and punch it (downshift into second).
So in actuality, my stock mount they called "weak" was stronger than the new one I have now? I purposely went to the dealer thinking I was going to get exactly what was originally on the car.
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From: Omahaish. Nebraska.
Well if the dealer in question is anything like the local ones here, they'll laugh at you for wanting that piece put in. You are probably better off doin it yourself, or having a buddy who's done those before help. I've "heard" it takes about a half hour tops to install one, so it's not a bad job. window motors are harder to do and I did one myself in about an hour.
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http://www.installuniversity.com/ins...y_mount_m6.htm
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Very easy, jackstands, a jack and some sockets and you can do it in the driveway. Here's a writeup:
http://www.installuniversity.com/ins...y_mount_m6.htm
http://www.installuniversity.com/ins...y_mount_m6.htm
Staging Lane
Joined: Nov 2007
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the new stock mounts are the same as the old ones as far as shape goes but yes it is a softer rubber and it move a lot more.....it may be real hard to see where the trans is hitting the tunnel....it will be on the very top and a small area of contact.....install is easy....get the front on ramps or jack stands.......support the tail end of the trans with a jack( you do not want the trans to drop down once you remove the crossmember bolts, you can really hurt yourself and damage your car), remove the center bolt that holds the mount to the crossmember....remove the crossmember,....remove the mount.....put the new mount on trans, bolt cross member back on, put the bolt that hold the mounts to the cross member back on. make sure you bolts are torqued to specs.......use the install univ. link, it has pictures. Its a good reference. let me knoe if you have more questions
Staging Lane
Joined: Nov 2007
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like i said before though if you get the ES mount...make sure you grind down the bumps on the top so its is flat agaisnt the bottom of the trans. and do not use the preload plate. this will change your drive shaft angle causing future issues
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Quick update:
I went to the dealer this afternoon to demonstrate the issue to the mechanic that worked on the car. He admits the tranny mount is NOT an OEM, but an aftermarket (he said it's supposed to be a good aftermarket replacement).
They agreed to get an exact OEM replacement and swap it out when it comes in.
I am also thinking, could it be the rear? I seem to experience this popping issue mostly when the rear wheels are breaking loose (although this has NEVER happened before replacing the tranny mount).
I went to the dealer this afternoon to demonstrate the issue to the mechanic that worked on the car. He admits the tranny mount is NOT an OEM, but an aftermarket (he said it's supposed to be a good aftermarket replacement).
They agreed to get an exact OEM replacement and swap it out when it comes in.
I am also thinking, could it be the rear? I seem to experience this popping issue mostly when the rear wheels are breaking loose (although this has NEVER happened before replacing the tranny mount).
Staging Lane
Joined: Nov 2007
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if you took it to a pontiac dealer. they are going to install a gm part, no aftermarket...i have a hard time believing that dealer is installing aftermarket part... I am not saying you are bullshitting,....but I think they are....can we get a picture off the "aftermarket" one they put in?
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I'll try to get a picture.
I did get a quick update and was told if this doesn't correct, it could possibly be a u-joint (I assume driveshaft). Then again, as long as I drive normal, everything seems fine.
EDIT -- They say it is about a $50 difference between the OEM and the one that they installed (OEM is more).
I did get a quick update and was told if this doesn't correct, it could possibly be a u-joint (I assume driveshaft). Then again, as long as I drive normal, everything seems fine.
EDIT -- They say it is about a $50 difference between the OEM and the one that they installed (OEM is more).
Last edited by Jeff 97 Formula; Jan 27, 2009 at 03:18 PM. Reason: pictures
Staging Lane
Joined: Nov 2007
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sure looks like a stock 97 trans mount to me. Also did you check you torque arm mount to see if that is bad?? I had the same issue you are describing, and replaced both and no more thumping. Have you checked your u joints? They are on the ends of the drive shaft
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Torque arm, not sure what to look for. It's still there, and is connected.
U-joints -- dealer said if the mount doesn't correct the issue, that's the next thing he's thinking.
http://frugalmechanic.com/auto-part/...ine-mount#fits
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Also, I had it on the highway at 55-60mph with no issues (afaik, this is the speed most f-body owners notice the effects from an unbalanced steel driveshaft). While going 55-60mph, I tried flooring it and it kicked back into 2nd gear, no issues there either.
Last edited by Jeff 97 Formula; Jan 28, 2009 at 08:02 AM.