Filling an ATX tranny mount

LionheartedSXT · Post by **LionheartedSXT** » Tue Mar 16, 2010 3:36 pm

I have done a numerous amount of searching and found a lot of information but just want to know what would be best in my case. 05 atx, I have agp solid mounts that I will be installing along with this tranny mount. Should I fill the tranny mount with window weld from autozone, liquid urethane from mcmaster & carr or something like that and go with a 60A, 80A or 94A durometer or a home depot brand of polyurethane? I know its pretty much all my preference, but I am already expecting a significant increase in cabin vibration after the install, but in anyone's opinion, what type of urethane do you think filling the mount with would best compliment the solid motor mounts? Thanks in advance.

Post by **occasional demons** » Tue Mar 16, 2010 10:55 pm

Unless you are also filling the center passenger side motor support, I would go with the 60A. You will be transferring the movement to that mount, if all the others are solid/near solid.

LionheartedSXT · Post by **LionheartedSXT** » Wed Mar 17, 2010 1:58 am

I see, so what if I didn't fill in the tranny mount? Wouldn't that cause the vibrations to go over to the driver's side then?

Danteneon · Post by **Danteneon** » Wed Mar 17, 2010 8:56 am

From what I have heard, when you go to "soild" mounts on the passenger side and leave the drivers side (trans) mount stock, you will get more vibration than if you upgrade the trans mount. This has been discussed on SRTfourms quite a bit. I'm in the same boat as you ATM. I still need to fill my trans mount.

As far as the durometer of the poly, I was looking to go with 92. But like you said, it's personal preference.

LionheartedSXT · Post by **LionheartedSXT** » Wed Mar 17, 2010 9:11 am

Well then I guess I will have to fill it then. But I was thinking a harder durometer like you such as 94a to match the solid "torque" mounts. But when OD mentioned that it would transmit vibration to the passenger side center mount that made it seem not worth it to go with as hard and go with like a 60a like he recommended. And to go the center mount out wouldn't I have to take out that tall engine bracket that covers the timing belt? Seems like a bigger pain than doing the tranny mount.

Danteneon · Post by **Danteneon** » Wed Mar 17, 2010 9:33 am

The center mount? Hahahaha!!!!

Okay okay...I'm done now. But yes, that mount is a pita to change. The engine mounting plate needs to be removed completly to get it out, and even then it's tight. You wouldn't know it by looking at it, but that mount is as wide as the frame rail.

I will also tell you that that mount on ATX cars is fluid filled. We found that out when we swapped Juan's car. My frame mount on the ACR was much stiffer...pretty much the same as a SRT.

LionheartedSXT · Post by **LionheartedSXT** » Wed Mar 17, 2010 9:45 am

lol, I actually saw one in the jy about a week ago and the entire motor was removed and I was like I had no idea there was a mount there, it is pretty big. But then I guess it makes sense why there is a pop off cap in the passenger side wheel well like there is in the driver's side

Hmmm interesting. Are all stock frame mounts(pass side) filled from 03-05 atx/mtx? Or maybe it was like that when he got the car? I don't remember seeing that frame mount at the jy filled but then again I didn't inspect it too much...

Danteneon · Post by **Danteneon** » Wed Mar 17, 2010 9:49 am

The ATX frame mount looks pretty much the same as the MTX mount. I didn't know it was fluid filled till we took it out. His was leaking a bit and when you shook it you could hear the oil in it. I pulled mine out when I did my timing belt to compare it. No fluid in mine, just a normal rubber mount, but pretty soild for a stock mount.

Post by **occasional demons** » Wed Mar 17, 2010 10:52 am

The center passenger side mount can be removed without pulling the MM plate. When I upgraded to the SRT mount, I just removed the torque struts, the transmount bolt, the MM bracket bolt, and lowered the engine/trans assembly enough to slide it to the driver side.

It only needs to go as far as needed to slide the center mount from the pocket. You need two floor jacks tho. One on each side to get the tranny lower, and to be able to move it. The exhaust will keep the engine pretty stable, and there is enough play in the halfshafts to let it move over.

Since you are removing the ATX mount, it will be easier to clear the frame rail. But it is handy to have a center mount already done to do this, obviously. IIRC someone sells inserts for the center mount tho.

Just take your time, and it will go well. The car needs to be properly supported of course.

LionheartedSXT · Post by **LionheartedSXT** » Wed Mar 17, 2010 3:22 pm

Idk I'm a little weary of not having the engine connected to anything at all and pretty much just free standing on jacks. I guess pretty much if I do the tranny mount, I might as well do the pass frame mount as well so then they would all be filled. So if I were to go that route, would filling the trans and frame mount with a high durometer urethane be too much? Since there would be very little "flex" I'm guessing being inside of the car would feel ridiculous and eventually be unbearable or would it just feel pretty much like stock except for the instant pedal response?

LionheartedSXT · Post by **LionheartedSXT** » Fri Mar 19, 2010 7:26 pm

Post by **occasional demons** » Sun Mar 21, 2010 2:54 pm

Well it's been a while since I changed the center mount, So I had forgotten how the inside had looked.

As you can see there isn't really much that can be done. I upgraded to the SRT mount, FWIW. I only know that after I installed the torque strut inserts, shortly after, you could tell that the trans, and center mounts were giving. I replaced the trans mount with a new one, and the center mount with the SRT one I got from latief.

So unless you want to spring for the SRT mount/fresh standard mount, I guess don't bother with it. Mine had over 100,000 on them, so it prolly needed done anyways.

5086709AB 2.0 mount
5085184AB 2.4 mount

Edit: As long as the exhaust is attached, the engine will not go too far, provded things stay on the jacks. A good garage floor will help. I placed steel plates under the engine bay in the parking lot. Rough asphalt doesn't make for a good rolling surface.

LionheartedSXT · Post by **LionheartedSXT** » Sun Mar 21, 2010 4:42 pm

If that is the case then I might just leave it and just fill the tranny mount. I think I might try out 80a for kicks to see how it works with the Solid mm's, hopefully it will be bearable.