This isn't a question about comfort, as I know they will make the vibrations from the engine more noticeable. But....

Will having stiff engine mounts cause the tranny to receive more stress? I work with my car and I daily drive about 100 miles every day sometimes more. I also like to drive it hard sometimes to get some giggles out of my day, will I set an early grave to my tranny if I go with the stiff engine mounts?

I want the harder mounts since I'll be adding an AST ACROSS carbon clutch and the T1R turbo later down the road and I want to have the most positive shifting action possibe.

 

With the trend in performance suspensions to replace soft factory rubber spring,sway bar, and transmission crossmember bushings with harder polyurethane with no ill effects, my bet is that polyurethane engine mounts will not negatively affect your trans. In fact, less movement will probably have a positive effect on the trans. performance and life span, either AT or MT.

Just my opinion, but I will probably install the polyurethane mounts in my own AT Fit in the future.

 

hard mounts wont wear out the transmission early but it will wear out your interior quickly. you'll start to get creaks and rattles from every possible place on your dash board after a couple months. although the car i had the mounts on was a 95 civic and the fit is a newer car. also depends on how hard of a mount you're talking about. i was running the HAsport hard race bushings which are rated at like 91a. basically like using a skate board wheel for a mount.

 

I plan on going with Innovative 60A rated mounts so I guess I'll have no problems. Thanks for helping me spend my money guys.

 

i can speak from personal experience with the Fit because I have the innovative prototype A/T mounts. I have had them on for over 5K miles and no problems whatsoever.

As for vibrations... the fit interior vibrated before. They did skimp out on insulating the dash so it does vibrate more. when i removed the stereo console to paint it a shuved some foam insulation in the gaps and it did stop it completely for a while but it did come back again (though not as bad) but ONLY when the car is cold on initial start up. Once it warms up it is fine. Much less vibrations than i expected; from what i heard people saying on this forum i thought the whole car would be shaking. Not the case. Only the dash is the problem. I am sure if i took the time to remove it and put some dynamat it would be eliminated for good.

Performance is much better. Especially in S-mode. no more wheel hop either. I have 60A side and tranny mounts and 75A rear mount.

 

It should not cause too much unless it is a "solid" mount (as in solid piece of metal). Then you will feel everything from the motor, but really poly mounts won't introduce much more NVH (noise, vibration, harshness). Good luck
-bix