Mitchy Posted June 23, 2019 Share Posted June 23, 2019 I was considering forking out $$$ once again for a group N (STI) transmission mount for the Legacy, as I bought one a few years ago and fitted it to the Forester with very happy results. Then I found the remains of the windshield adhesive sealant I had recently used to toughen up the Vivio’s failing engine mounts, and I then dug out the Forester’s old soft transmission mount, still in one piece... ....So I am experimenting with... One original Forester SF trans mount, Two unused hard rubber bushes from a Fiat Panda’s trailing arms, 1/2 tube of windshield adhesive/sealant. - -Thoroughly clean and degrease the mount, and force in the bushes (bench vise did the trick): -Tape up one side to prevent seepage: -Squeeze in sealant from the open side as thoroughly as possible: -Do what you will with the excess, and leave to cure for a few weeks: When it is cured I shall remove the Legacy’s existing mount and compare them both in the hand, before fitting and coming back with an update. I am expecting a firmer mount, though not as stiff as the real STI component. Quote Link to comment Share on other sites More sharing options...
carfreak85 Posted June 24, 2019 Share Posted June 24, 2019 It will be pretty firm. I've got the Group N mounts in my WRX and RX-RA and they're just fine. Filling in the voids will transfer a lot more NVH into the cabin, but the mount will be stiffer, for sure. Quote Link to comment Share on other sites More sharing options...
Mitchy Posted June 24, 2019 Author Share Posted June 24, 2019 (edited) I do not mind a little extra nvh, as it will likely muffle the rattling trim. The SF Forester with the real STI mount only really showed extra cabin noise as a growl under heavy acceleration- sweet! The good lady did not notice any change except for the ‘stiffer knob’ . Obviously. The Legacy feels sloppy in comparison with its 22yo rubber. Edited June 24, 2019 by Mitchy Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 24, 2019 Share Posted June 24, 2019 (edited) not as cheap as DIY I'm sure, but user traildogck makes some trans and motor mounts and some other bushings. I think he sells thru ebay. ?? paging @traildogck Edited June 24, 2019 by 1 Lucky Texan Quote Link to comment Share on other sites More sharing options...
Mitchy Posted June 25, 2019 Author Share Posted June 25, 2019 I’ll have a look... thanks Quote Link to comment Share on other sites More sharing options...
Mitchy Posted June 25, 2019 Author Share Posted June 25, 2019 (edited) This is definitely the cheapest option; The sealant already paid for itself in the repair of a full set of another Subaru’s engine mounts, the two bushes were left-overs from a resto project, and the mount itself is also a left-over, until now sitting on my shelf waiting to be thrown out. Time will tell if it is successful. I may end up putting the DIY part on the beater Forester and using the nice newish STI part (presently on the Forry) on the Legacy instead. Its such a quick and simple job. Edited June 25, 2019 by Mitchy Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted June 25, 2019 Share Posted June 25, 2019 It would be better and cleaner to use pourable urethane. I've used the pourable silicone and urethane from smooth-on and the stuff is amazing. GD Quote Link to comment Share on other sites More sharing options...
Mitchy Posted June 26, 2019 Author Share Posted June 26, 2019 (edited) 90 degrees today so I am hiding under the cars- As I was underneath the Forester changing oil, I thought I might as well take the fairly new genuine STI mount off and swap back the now-modded OEM item. The Forester has a little more room to work underneath than the Legacy, so the Legacy is now getting the real STI group N part, hopefully never to be changed again.... If the modded one fails it is now more convenient to change it on the Forester! Plus I now have the original Legacy mount, which I may try GeneralDisorder’s tip using urethane: On 6/25/2019 at 7:14 PM, GeneralDisorder said: It would be better and cleaner to use pourable urethane. I've used the pourable silicone and urethane from smooth-on and the stuff is amazing. GD So now for a quick bolt-up job on the Legacy with the harder mount, and time go for a spin!! Group N mount vs. original Legacy: Edited June 27, 2019 by Mitchy Quote Link to comment Share on other sites More sharing options...
Mitchy Posted June 26, 2019 Author Share Posted June 26, 2019 (edited) As expected, driving the Legacy is transformed by this simple and highly-recommended modification. The genuine STI (group N) part provides more precise gear changes, gear stick stiffness, the car feels more stable as the transmission is now properly ‘held’ against the g-forces in corners, over bumps on our track, and various other general sounds of ‘looseness’ have been eradicated. If that was not enough, the classic lurching at low speeds whilst coasting in gear has been reduced by about 3/4. If one can handle the NVH; at idle and gentle revs/ low speed, the difference is unnoticeable, but accelerating at and above 3000rpm there is a loud growl. (Smile) This then disappears when cruising at high speed in 5th, though there is a negligible rise in engine noise overall. I love it, I can hear the engine better which I prefer as I can monitor my cars health ‘by ear’, and the modification has as a bonus removed some unwanted rubs and clunks from underneath, those typical noises which could have been.... faulty engine mounts...exhaust hangers... suspension bushes...track control arms.... etc. etc. Edited June 26, 2019 by Mitchy Quote Link to comment Share on other sites More sharing options...
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