I was hoping to get some opinions on this as I have a little more information about the whirring noise in my driveline.
I originally posted (See Previous Post
) about a whirring sound and vibration at speed when the engine and driveline where in "sync". That is to say I had no positive load (accelerating) or negative load (decelerating) between the engine and driveline. So basically I could "coast" at 70mph and hold the engine speed up with the throttle and get this noise. The noise/vibration was also noticeable for only a second as I transitioned from a downhill coast to an uphill climb.
First thoughts and replies on the earlier post were realted to failing carrier bearings and/or u joints. I still have to replace these so they may still be the issue...however on the advice of an RV mechanic I tried something on the last trip that adds a little more information to this noise.
His opinion was that this could actually be in the torque converter or the parking brake...based on my description and the fact that most of the noise and vibration inside the coach seems to be up near the doghouse rather than back by the door (where the first carrier bearing is located).
He suggested that I get up to speed, coast on a downhill and CAREFULLY put the transmission in Neutral. His thought was by "disconnecting" the engine from the driveline and checking for the same noise it would point toward the converter, transmission, parking brake area. Sure enough on my last trip I tried this procedure and the noise and vibration were there and consistent.
So...even though I'm still replacing the bearings and u-joints. Does anyone else think based on this additional "test" that I have an issue in the converter/transmission/parking brake area?