So its on the floor, just laughing at me. The transmission.


Well, not really. But I do have to clean it up. The transmission mounts are a wear item right? 928intl sells them used and new, so I was thinking that they didn't wear out. I think the do, though, as I was able to make the trans move a bit with my foot when it was still in the car.

I guess I wanted to see if anyone has any anecdotal info on these mounts before I plunk the 140 bucks for something that I might not need.

I mean, technically, all the motion that the rear wheels impart to the half shafts is supported by two rubber mounts.

I wonder if I could have some harder ones made?

 

New tranny mounts are planned for my 87S4. The drive train is only suppoted by the motor mounts and tranny mounts.

 

My thought exactly. I am currently seeing if I can get some more solid ones made.

 

Why get harder mounts? I'm certain that the Porsche engineers designed the mounts to absorb impacts from the drive train and harder ones would not improve handling, but would put the transmission at greater risk.

 

You know me Ernest. Always trying to reinvent the wheel.

I just remember the feeling of the transmission moving, and I could feel it through the gear shift.

 

I've thought of replacing mine with stiffer ones too, but
soft motor mounts and hard tranny mounts may put extra
strain on the torque tube. Some drag racers have sheared trans
mounts under severe stress. Granted, they had 1000hp Chevys,
but at what point does the problem surface?
If you're feeling brave, there's a product called 'Flexane 80' made
by a company called Devcon, if you want to cast your own. It's as
strong as polyurethane, and its' durometer falls between rubber and
the typical poly used for bushings. They use it for undustrial
vibration damping. If I dare use it, I'll cast new motor mounts too,
and let you know. I've played with a can before, and it's WAY strong!

 

you can use poly euathane plates and insert as a plate on the old ones

 

Flexane 80. I will look into that. Thanks Wolf.

How do you mean plates Lizard?

 

Brendan,

I think Wolf is refering to an insert (if you will) that fits into the voids in the standard rubber type flex mounts.

The import scene has been on this for years. Take the factory mounts and insert a void "plug" that has a plate on it to keep it from sliding out under pressure.

A cheap(ish) fix, not as consistent as a completely "recast" mount, but they do seem to function.

Greg

 

Greg described it perfectly

 

I replaced the tranny mounts on my '88 S4 after still experiencing some vibration with new motor mounts. The motor mounts got rid of about 80% of the vibration. New tranny mounts made a significant difference and took care of most of the rest of the vibration. Make sure they are shimmed properly per the manuals.

 

Brendan,
If the old ones lasted 14 years and worked great, why would you want to try something unproven that may transmit more driveline vibration through them and you have no history on its expected life under temperature cycling and with a constant load on it. Not to mention oil soaking if the car leaks. I'm sure Porsche put a lot of engineering time and $ into their choice. Now if they only put that same time and $ into the damn shift handle, we'd all be happier. I would think that $140 for 14 yrs is a good investment. I'm not trying to ruffle any feathers, I just think its a lot of work to do what your proposing. We use Flexane at work for vibration weld nests and if you use it, your going to have to make a mold of your part and make sure it doesn't leak while the Flexane sets up. Not to mention having to encase the metal pieces of the mounts within the Flexane or risk the metal tearing away from it. If it does tear away, your tranny will not be attached to the body and seeing as your tranny mounts are 50% of what holds your driveline to the body, I feel its too risky to chance. Best of luck in your choice, but make sure you give it lots of thought.

 

Your right.

I use Ford mounts for the enigne, and I would us a replacment here, but it looks as though there is nothing that compares very well.