996 997 Transmission Mount Diagnosis and DIY In Your Driveway Urethane Mount Installation

Another good video. If you don't have an air chisel you can use a drift and a hammer at an angle, then there's no chance of saw teeth added to your transmission yoke. Dictator, do you think the solidification on that mount has any detrimental affects, harmonic vibration or the like? Porsche used that same design in the 986, it seems like the heat cycles damage those fine TUV German polymers, they all fail the same way. Seems like there might be more to that design that ride comfort, just my two cents.

A word of caution ⚠ the aluminum alloy used for the housing in which the urethane bushings are "pressed" into are very soft. I was going to use a hammer also but it flexes so much that I personally would not attempt hammering on the aluminum. If feel it will easily deform.

Also, discussing the solidification of the mount, Cantrell also sells a solid version and an even harder urethane so I doubt others are experiencing broken carriers. This mount has been in my wife's daily for a couple of years now and the mount does not appear to have broken.

Finally, I do not recommend installing any harder mounts without doing the engine and trans as a set. Meaning reducing flex in an object that is held in 3 locations can induce breakage.

Not at a severe enough angle with a gentle touch and a small hammer. I have several tiny ones. Certainly, you don't go at it with driving force, if a gentler approach fails you can always bust out the saw blade.

Agreed, we share the same goal, make it better than we found it and do no harm.

Have a blessed weekend

Those bushings look awesome you'll have to let us know if the stiffness is perceptible, after them being broken it's going to be a dramatic change either way. ☮

Boristhespyder said:

Those bushings look awesome you'll have to let us know if the stiffness is perceptible, after them being broken it's going to be a dramatic change either way. ☮

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I did the Cantrell trans mount with RSS engine mounts.

I have done literally thousands of performance upgrades throughout my career and those two pieces on a 996 or 997 are undoubtedly one of the most memorable upgrades you can do to that platform regardless of cost. I realize that is a strong endorsement but I absolutely stand by those words. The ride is ever so slightly harsher but the upside gain in precise handling and road feel aren't even quantifiable, it is a light year of improvement. You'll sweat it's a different car. And by harsher I mean do more so than my GT3 in Sport mode.

I changed everything to urethane in my 280ZX . At that time I thought I could make it a 260Z, I could not. Luckily though, it was an awesome car to do long miles in and I used it that way a lot.

FYI, Rennline offers a urethane transmission mounts that have three different elastomers, in case you don't like the added vibration, you can easily change the rubber part for a softer one, I use these on my 987CS for a few years and was very happy with the results

V=Porsche Rennline Tunable Semi-Solid Engine or Transmission Mount PAIR Rennline Design | Pelican Parts

Gilles said:

FYI, Rennline offers a urethane transmission mounts that have three different elastomers, in case you don't like the added vibration, you can easily change the rubber part for a softer one, I use these on my 987CS for a few years and was very happy with the results

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The mounts Rennline offers are the Cantrell urethane mount that were depicted in the video.

Nice work, thanks for the share.

Moving this to the 911 DIY forum. Congrats! It's earned an Outstanding Technical Contribution attribution!