grinding noise when coasting

[srd]

I have a '05 T4R limited V8, which is all wheel drive. When I let off the gas, there is a grinding noise while coasting that goes away when you accelerate. I've read many threads and all seem to indicate that it is either a grease issue with the drive shaft or U Joints. I replaced the U Joints on the rear drive shaft last weekend but that did not resolve the issue. The rear drive shaft took almost no grease but the front took a lot. That did not eliminate the noise either. I'm now down to assuming that it is the U Joints on the front drive shaft but thought I would check with some experts before I start on that project. Any help on diagnosing this would be appreciated.

 

[Bob J]

I have a '05 T4R limited V8, which is all wheel drive. When I let off the gas, there is a grinding noise while coasting that goes away when you accelerate. I've read many threads and all seem to indicate that it is either a grease issue with the drive shaft or U Joints. I replaced the U Joints on the rear drive shaft last weekend but that did not resolve the issue. The rear drive shaft took almost no grease but the front took a lot. That did not eliminate the noise either. I'm now down to assuming that it is the U Joints on the front drive shaft but thought I would check with some experts before I start on that project. Any help on diagnosing this would be appreciated.

Might also be worth a look at your CV's.... Does the sound change when you are turning to one side or the other?

 

[srd]

Might also be worth a look at your CV's.... Does the sound change when you are turning to one side or the other?

The noise does not change with turns. It only seems to be affected by whether or not I am accelerating. It is most pronounced between 20-40 mph and less noticeable at highway speeds.

 

[Bob J]

The noise does not change with turns. It only seems to be affected by whether or not I am accelerating. It is most pronounced between 20-40 mph and less noticeable at highway speeds.

Ah, not CV's then..... You are back to U joints being the most likely culprit.... The offending one should have noticeably more play in it...

 

[srd]

Ah, not CV's then..... You are back to U joints being the most likely culprit.... The offending one should have noticeably more play in it...

Thanks, maybe it will be apparent once I pull the drive shaft. There is no detectable movement I can feel with it in place.

 

[Jeff S.]

Sorry to bump an old thread, but was this ever resolved?

I have the exact same thing in my V6 '04.

There is a slight grinding sound when I coast, or let off the gas. The faster I'm going the more noticeable the sound. It only happens while in 4hi or 4lo. Doesn't happen in 2hi. How much to replace a U-joint, and will there be any damage done if I wait to replace it?

I've been searching and this thread is the most similar situation to what I'm experiencing, hence the thread bump.

 

[oljedi11950]

"rumble strip noise" this is possible torque converter ! Going to dealership to have mine checked tomorrow .

 

[Stuck CAPS]

I assume its Torque converter, although [MENTION=78968]oljedi11950[/MENTION] never followed up. Its called "converter shudder." Its when the converter is womanly and wont make up its mind about slipping or grabbing.

 

[oljedi11950]

Ya dealership didn't give me any satisfaction on it . Had a pm from a member who told it's def the tc & try stuff called shudder fix , just haven't done it yet . He told me he replaced his & it still came back 5g later so ...... I don't mention his name because it was private but maybe he jump in when he see's this .