Motor mount and shifting

[RandallNeighbour]

For the life of me, I cannot figure out why replacing a worn front motor mount would make shifting smoother. I'm sure the cables leading from the shifter over the motor and to the back of the tranny do move up a bit when the new motor mount is in place, but this shouldn't make that much of a difference... or does it?

Or, is there something totally different of which I am totally unaware?

Somebody smarter than me should now educate me. I'm all eyes and ears on this end.

[ppbon]

When the motor mount cracks, it allows two things that weren't there before:
a) The front of the engine settles down a bit (1 mm to 10 mm).
b) The engine will "twist" sideways as you accelerate.
Both of these movements put undue tension and misalignment into the shifting cables, making it harder to shift gears.
I've seen some cars where you could not shift into 2nd gear because of a bad front engine mount.
Happy Boxstering,
Pedro

[RandallNeighbour]

Pedro I was hoping you would be the one to educate me on this.

I am confident I need a new one. But I want the least amount of vibration, even if the material in the mount goes out again in 25000 miles.

Should I order a factory one?

All the aftermarket ones I read about, including yours, talk of added vibration due to the material used in the bushing to make it more durable.

[kyleturner2020]

Great question Randall, I believe I could use a new one too. I was eyeing Pedro's "enthusiast" version, but not sure the difference to OEM.

Kyle

[Daniel R]

I installed Pedro's Race Mount several months ago, my original mount had almost completely disintegrated.

The Race version of the mount does give more vibration, particularly at 3,000rpm. I don't have a problem with it, just don't cruise at 3,000. I either go faster, upshift or downshift. The vibration is minimal at other engine speeds.

For me, I see the benefit in a rigid engine mount. Less power is lost in hard acceleration, as the torque cannot lift the engine up. Also handling is better as the engine doesn't shift around whilst cornering. I am now considering replacing the transmission mounts with some semi-solid type to really tie things down.

At the end of the day, we own sports cars, if I had wanted a comfortable ride I would have bought a Mercedes.

[Spinnaker]

Replaced my front motor mount a year ago with OEM mount. The old one was totally shot. Shifting improved tremendously afterwards, especially going into second gear. Used to have trouble with it popping out of gear and getting false shifts when going into second gear. It got so bad that I started to shift from first to third, skipping second. New mount got rid of all that.

[kyleturner2020]

Originally Posted by Daniel R

I installed Pedro's Race Mount several months ago, my original mount had almost completely disintegrated.

The Race version of the mount does give more vibration, particularly at 3,000rpm. I don't have a problem with it, just don't cruise at 3,000. I either go faster, upshift or downshift. The vibration is minimal at other engine speeds.

For me, I see the benefit in a rigid engine mount. Less power is lost in hard acceleration, as the torque cannot lift the engine up. Also handling is better as the engine doesn't shift around whilst cornering. I am now considering replacing the transmission mounts with some semi-solid type to really tie things down.

At the end of the day, we own sports cars, if I had wanted a comfortable ride I would have bought a Mercedes.

Could you elaborate on the "vibration" a little bit? Everything rattles, car shakes, etc.?

Thanks-

Kyle

[Pat]

Originally Posted by Daniel R

Also handling is better as the engine doesn't shift around whilst cornering.

You're joking, right?

[Globespy]

I read Pedro's DIY 'Front Engine Mount' article and was wondering if I need to do this on my 2005 987 Boxster S?

I am about to replace a failing water pump and noticed that the article suggested the front engine mount replacement while I was in there.
Not sure if the same issues with the mount apply to the 987?

Thanks.

[yimmy149]

Originally Posted by Globespy

I read Pedro's DIY 'Front Engine Mount' article and was wondering if I need to do this on my 2005 987 Boxster S?

I am about to replace a failing water pump and noticed that the article suggested the front engine mount replacement while I was in there.
Not sure if the same issues with the mount apply to the 987?

Thanks.

It's worth considering, I think they've revised the part some in the 987, but I think it will still fail. When you have all the panels off for the waterpump, you can sort-of see the cylindrical portion mount. If you get enough light shining on one side you should be able to see if it's cracked.

If I were in your shoes, and the car had 30k miles or more, I'd just replace it. You will need something to support the weight of the engine, either an engine support bar or a jack that doesn't leak-down.

-james