Engine Vibration
Tech Contributor
Joined: May 2008
Posts: 2,843
Likes: 16
From: Howell Michigan
St. Jude Donor '09-'10-'11
Hey, that is great news..I been lurking for some time now. Glad to see you will now get some seat time driving. Spend too much time on the underside of the car and you many never get back from the Dark Side!
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Just glad you got it all worked out and all is good. This is one project that you'll not soon forget.
The vibration in your shifter may be from the Pfadt mounts or if used any aluminum couplers in the torque tube.
The vibration in your shifter may be from the Pfadt mounts or if used any aluminum couplers in the torque tube.
Hmmm......in the immortal words of Stewie Griffin........
Just took her for a spin and it was NICE and SMOOTH!!!!!! There was a little vibe coming through the shifter which I'm attributing to the Pfadt motor mounts, but there was not of the teeth loosening RPM related vibration I was experiencing before!!!!!!!!!!! Hallelujah I think we got it!!!! Paranoia seemed to be running rampant yesterday when I fired it up which is why I told myself to put it back together and drive it before making a rash decision. I only needed a quick blast up and down the street to about 50 mph to verify and she was nice and smooth again!
Going to get it to PBJ this week for a little better baseline tune, and do some break in on the motor. First.......she's getting a BATH!!!
I want to offer a sincere thank you to every person who had input during my searching of this issue, and a very special thanks goes out to AJG1915 who kindly sent me a couple of tools to help working on the car. Situations like this is why the place is as great as it is, and I'm truly thankful to be a part of it. Thank you all for your help and support. I only hope I can be as helpful in the future.
Updated thread to come once it's tuned and everything is good to go, unless more problems arise.
Just took her for a spin and it was NICE and SMOOTH!!!!!! There was a little vibe coming through the shifter which I'm attributing to the Pfadt motor mounts, but there was not of the teeth loosening RPM related vibration I was experiencing before!!!!!!!!!!! Hallelujah I think we got it!!!! Paranoia seemed to be running rampant yesterday when I fired it up which is why I told myself to put it back together and drive it before making a rash decision. I only needed a quick blast up and down the street to about 50 mph to verify and she was nice and smooth again!
Going to get it to PBJ this week for a little better baseline tune, and do some break in on the motor. First.......she's getting a BATH!!!
I want to offer a sincere thank you to every person who had input during my searching of this issue, and a very special thanks goes out to AJG1915 who kindly sent me a couple of tools to help working on the car. Situations like this is why the place is as great as it is, and I'm truly thankful to be a part of it. Thank you all for your help and support. I only hope I can be as helpful in the future.
Updated thread to come once it's tuned and everything is good to go, unless more problems arise.
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
Yea!!! I am happy you got it running smooth too. Since I also have the Pfadt motor mounts, I do have a very small vibration at idle, but know I have solid motor mounts, I expected it. I would rather KNOW my motor is held solidly then to have rubber holding it!
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Thread Starter
Race Director
Joined: Mar 2004
Posts: 12,466
Likes: 886
From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
C5 of Year Finalist (performance mods) 2019
2017 C5 of the Year Finalist
2016 C5 of the Year Finalist
2015 C5 of the Year Finalist
Soft stock motor mount on the passenger side appeared to be compressing too much, kicking up the driver side of the motor causing a clearance issue between the T3 flange and the transmission tunnel. New motor mounts evened out the motor and gave me the clearance I needed.
It's going to PBJ tomorrow for some baseline work, then as soon as I can get it in after it's broken in for a full road/dyno tune!
Stay tuned, I'm going to dissect the stock motor mounts under the suggestion of Bill Curlee, and post up what makes them tick in this thread.
It's going to PBJ tomorrow for some baseline work, then as soon as I can get it in after it's broken in for a full road/dyno tune!
Stay tuned, I'm going to dissect the stock motor mounts under the suggestion of Bill Curlee, and post up what makes them tick in this thread.
Thread Starter
Race Director
Joined: Mar 2004
Posts: 12,466
Likes: 886
From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
C5 of Year Finalist (performance mods) 2019
2017 C5 of the Year Finalist
2016 C5 of the Year Finalist
2015 C5 of the Year Finalist
Hey Bill, this one's for you: Motor Mount Dissection!!!
First couple of pics you can see how much fluid is in the mounts. And I spilled some out of the container too. There was a solid 6 oz of fluid in there if not more.
In the third pic, you can see where I had to go to get to the fluid. I'm going to continue that cut all the way around and see if the mount comes into two pieces. What I'm expecting is that the one piece is a big "bucket" per se, with a thin rubber coating over the entire thing. Then the second piece is only a small chunk of metal that sits in a thick rubber end section of the first piece, with fluid filling the center. Not a lot of technicality to it. Definitely has the ability to get saggy though. More to come as I get the urge to cut something up.
First couple of pics you can see how much fluid is in the mounts. And I spilled some out of the container too. There was a solid 6 oz of fluid in there if not more.
In the third pic, you can see where I had to go to get to the fluid. I'm going to continue that cut all the way around and see if the mount comes into two pieces. What I'm expecting is that the one piece is a big "bucket" per se, with a thin rubber coating over the entire thing. Then the second piece is only a small chunk of metal that sits in a thick rubber end section of the first piece, with fluid filling the center. Not a lot of technicality to it. Definitely has the ability to get saggy though. More to come as I get the urge to cut something up.
Thread Starter
Race Director
Joined: Mar 2004
Posts: 12,466
Likes: 886
From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
C5 of Year Finalist (performance mods) 2019
2017 C5 of the Year Finalist
2016 C5 of the Year Finalist
2015 C5 of the Year Finalist
This is the ONLY hairy arm picture that I have. I have LOTS of dirty fingers and hands pictures but,,,,,,,,,,,,,,,,,only ONE hairy arm pic!
