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Can you adjust motor mounts?

Yesterday on my 2004 CRV 2wd I changed out the upper trans mount and front motor mount. Both of which were badly cracked and causing a vibration/rumble when turning and accelerating. This seems to have fixed 90% of the issue, however when I turn Left, and only left while giving the CRV moderate gas I still get the vibration/rumble. So my question is, is it possible I have the trans mount out of adjustment?? (the motor mount seems to only install one way, so I think Im ok there). It looks like the trans mount can be moved slightly, so if it can be adjusted does any one know how?? Any other ideas on what can cause a vibration/rumble when turning left only when giving it gas??


CV joints.

Thanks MT, but it does not click if you go in circles (left or right)… THE ONLY time I hear it is if when turning left I give it moderate gas. If I am very light or idle thrugh, then I get nothing…

Before you completely dismiss “MT”, you should check the CV joint boots. If they are intact, then the CV joints should be good, but the clicking only occurs after severe wear. It could still be the CV joints.

You may have a motor mount called a dogbone, or a vibration damper that goes between the engine and the firewall. This could be bad as it is usually the first motor mount to suffer damage. Some of the vibration dampers are a mini shock absorber where a dogbone is a rubber mount that looks like a dog bone.

In a previous post (of your’s) I suggested it might be CV joints and I suggest it again.

More specifically: inboard CV joints.
Bad outboard joints click in turns.
Inboard rumbles.

OK, If it was the inboard CV joint would it make the noise unloaded on a lift?? How can I test this theory so I dont just thow money at the problem?? THANKS GUYS !

Since it only happens on turns, I don’t see the inner CV joints causing this issue. They are not affected by steering.

Actually, Keith, I would argue that they are. The length of the axle may change a bit in turns just as it does when the hub is traveling through its suspension path. The three bearings on the inner portion slide a bit out of their atatic location in the inner CV housing.

Just turning the wheel doesn’t change the axle length, that is a function of the change in the vertical angle of the control arms, i.e. the body going up and down. It is true for most vehicles that when in a turn, the body rolls which results in a change in the vertical angle of the control arms, but then so does going down the road and hitting bumps and even the normal vertical oscillations of the body.

If it was the inner CV joint, I would expect that the vibration/rumble would also occur while going in a straight line, but it would be very short duration with a steady periodic rate of occurrence plus when ever hitting a bump. I still think its the outer CV joints but it could be the dogbone or equivalent.

Now if gsragtop tries a full throttle acceleration where the whole vehicle tends to raise up, or at least the front rises, and the vibration/rumble occurs, then I fully agree on the inner CV joints. Or he could jack up the front end so that the axles are at their max length and put it in gear and see if it happens at a low speed. Using jackstands and wheel chocks of course.

I might add something to mountainbike’s comment about the inner balls or bearings as the case may be changing their static position.

On a few occasions when finances were an issue and someone had a borderline inner joint I’ve removed the snap ring, flipped the inner race assembly around, and reassembled it. The tiny amount of offset would cause the balls or bearings to sit in a slightly different orientation and the joint would be snugged up due to the wear area moving ever so slightly.
This is really not a good practice but it can work. I even did this on a Subaru of mine once and got another 40 or 50k miles out of that shaft.

Thanks again guys… I put the car on a lift at work, and with the wheels off the ground and CRV in gear I got no noise even while giving it gas… Even if the wheel was turned… So it seems to only happen when the suspension is loaded and turning “force” is being applied to the drive line. Again it has to be moderate to hard acceleration on a left turn only. Prior to the new motor mounts, it would make this same sound while accelerating straight or turning right as well. With the new mounts it only does it on left turns…

It is something I can make happen, or just as easily not make happen… Other then that the truck drives amazing for 230,000 miles.

Keith, I disagree. The axle length is a function of the distance between the outer CV joint and the output shaft. That can vary both as a function of vertical movement of the axle thrpough the arc established by the control arms and as a function of the rotation of the axle assembly around the axis of the upper and lower ball joints…or a combination of both. One of the inner CV joint’s two principle functions is to allow changes in the axle length as the suspension and steering arcs and angles interact while still transmitting torque. It also allows limited articulation,

Said diferently, the CV joint’s vertical axis of rotation is not and does not need to be exactly the same or even coaxial to the horizontal axis of rotation of the ball joints. The inner CV joint allows the axle to change length to allow for freedom of the axes to be different.

The only way the wheels could turn without changing the axle length would be if the outer CV joint’s vertical axis of rotation were exactly in line with the axis of rotation created by the upper and lower ball joints.

I stand by my post.

“The only way the wheels could turn without changing the axle length would be if the outer CV joint’s vertical axis of rotation were exactly in line with the axis of rotation created by the upper and lower ball joints.”

It pretty much is.

“Pretty much” isn’t good enough. It would need to be exact. And it isn’t. From a design standpoint, it doesn’t need to be. The inner CV joint is there to take up the difference. And it does.