Dear Forum,
First time user...
Bought a new to me 2008 civic hybrid with 96,000 miles...
Love the car, runs smooth and quiet, battery slightly weak but it used to sit a lot...
Previous owner said dealer recommended changing trans mount on driver side...
I could feel some movement from the engine/transaxle assembly during D-N-R changes and on takeoff so I figured they probably were correct about the mount...
I changed the mount, it was slightly (25%) torn, see video...
After the change, the rumbled very badly, especially when turning to the right, see ...
I could use a pry bar against the mount to eliminate the noise...
I tried adjusting the mount in the bolt slots as far to either side as it would go, and noise improved but did not go away...
What is going on, does anybody have experience with this? I suspect the other side mount may be faulty/collapsed... (see pic)
The rumbling is very bad and terrible to drive the car, so bad I want to put the old mount back on!! The main reason I bought a new car is my old 94 civic vx was SO LOUD!!!!

Thanks,

 

It sounds like you have an aftermarket exhaust. Can't tell anything from the video.

Replace the passenger side mount and the torque link.

Kinda an all or none thing.

Begin budgeting immediately for a replacement hybrid battery.

Good luck,

Steve

 

Hi S Keith,

Thanks for your comments on the vid and on the board. The "aftermarket exhaust" sound is the rumbling from the mount, if you listen carefully it goes away whenever I steer to the left.... so confused why this noise was not there before I changed the mount and now it is. Rumbling noise and vibration from my old car's motor mounts is what caused me to sell it.

Couple questions, you mentioned it was easier to pull the fuse box, is there a trick disconnect the wires underneath?

Also, why replace all the mounts, just out of curiosity, do you have experience with this?

Thanks,

 

I could hear the change. My 1st 06 sounds very "rumbly" until it really gets warmed up.

Either you did it wrong, installed the wrong mount, or the new mount has altered the geometry to accentuate the issues with the other two mounts.

The main harness attached at the back inside corner. There is a single zip tie securing everything there. Cut the zip tie and the fuse box bottom can be dropped and the plugs can all be disconnected from underneath the panel.

Because they are all rubber, and they all age/wear.

Yes. Replaced all three on HCH2 #2 before I sold it.

Here's what my tranny side looked like:




Steve

 

Steve,

Mine looked similar except only 50% cracked on that same piece of rubber. How did you know the others were bad? Did you just replace them all together for PM?

 

Process of elimination. I replaced the torque link because it was cheap and easy... no change. I replaced the transmission mount because that's the one everybody says fails... minor improvement. I replaced the engine mount because that's the only one left. Smooth as glass.

The engine is held up by rubber. That rubber won't last forever. All pieces of that rubber are subjected to the same time, thermal cycles and loads. It makes sense that they would all have similar lives.

 

Glad to know you finally got it fixed, I was concerned that you never cured the rumble! A mechanic friend of mine suggested loosening all the mounts and re-tightening after the motor settled in a neutral location, but if I'm going through all that trouble I will replace them, I already ordered the new ones. My only concern is new rubber is harder rubber and if it is so stiff that it causes a rumble / vibration I will be very sad My '94 VX eg had hard race engine mounts that were about double the durometer level of the original rubber, and they were unbearable....

 

As rubber ages, it sags under load, hardens and loses its elasticity/ability to damp vibration. Between tearing, hardening and sagging, it loses it damping ability and transmits more vibration to the unibody. I would make sure the "arm" that connects to the mount isn't somehow impinging on the mount itself.

Did you use OEM parts or aftermarket? I've had mixed results with aftermarket - wrong size threads on top of tranny mount (fixed with tap) and incorrect engine side mount.

I'll be replacing the engine and tranny mounts on HCH2 #1 soon. It's a rumbly bastard, particularly during first start-up on a

 

I only use dealer mounts now out of hardship and experience, I used to run a 3 million dollar shop and ESPECIALLY Honda and Acura aftermarket mounts were never any good. Particularly the electronic and vacuum actuated aftermarket mounts are total crap. Also lots of problems with stripped bolts and studs.

Going to pick up the engine mount and torque mount now will post again with video after installation.

BTW I believe the passenger side engine mount is hydraulic (fluid filled) and they usually do not go bad, however they can collapse and be hard to notice, also they can rupture and fluid comes out in which case it is done.

 

Hope you get it sorted.

Steve