[V8] Still Have Vibration & Noise in 91' V8 Help!!

urq urq at pacbell.net
Wed Apr 1 08:28:28 PDT 2009


... the fact the torque mount separated does indicate that one or more
engine/transmission mounts are bad.  I'd recommend that you remove the top
bolt on the torque mount temporarily until you get the problem fixed ...
otherwise you may have another torque mount to replace.  

You may want to crawl around under the front of the car to check clearance
between the oil pan and the subframe ... if there is little or no clearance
it confirms that the motor mount(s) need to be replaced, and there's a good
chance this will resolve the roaring sound ... don't see this as being a
cause for vibration though.  

The V8 mounts are expensive because they are hydraulically damped ... when
the 5000's were new they had similarly expensive mounts.  Please investigate
further, but ISTR that the part number for the I-5 motor mounts cross
references to the V8.  

Allan suggested there may be a different bearing to blame ... I would second
that opinion ... Bearing noises can change depending on the side load on the
bearing, if you notice a change in the rumble turning left vs. turning right
it might point to a wheel bearing.  I had a bearing inside the final drive
fail on my '78 Fox ... this is probably a rare occurrence.  

Does your car still have the belly pan?  If it is not secured all the way
around the periphery it may cause a vibration that is difficult to pin down
... 

Steve B
San Jose, CA (USA)

-----Original Message-----

I have a 91' V8 that has a front end vibration and roaring sound that I'm
trying to solve. So far according to recommendations from folks I've
replaced what was thought to be a bad wheel bearing, which we replaced and
had no effect.  Then we found an inner C/V joint that was very dry - and
replaced the whole axle with one we had - no change with a road test. We've
changed the diff oil (it looked OK when drained if a little low), and
listened with a mechanics stethescope with the car running on the lift right
on the diff and it is not making any noises to suggest bad pinon or carrier
bearings. We did find the front engine mount to be broken (what's referred
to as the "anti-torque" mount) and replaced this forward mount - again with
not much change. I took it to a transmission specialist and they suggested
it could be the drivetrain is still twisting causing contact somewhere along
the line. New engine mounts are very expensive for the V8's vs. the 5 cyl.
mounts - and I don't want to put more money into this car if it isn't the
root of the problem. The sound it makes is a fairly loud dull roar - not
metallic sounding like metal surfaces turning hard like a bad bearing. It's
almost like a really bad tire, but I've rotated them front to back. Any help
out there? Thanks!

Corey




More information about the V8 mailing list