Grinding / rumbling noise when I let off the gas - 2011 Trail

My 2011 Trail Edition is making a grinding noise when I let off the gas and it sounds like something drivetrain related. It goes away as soon as I step on the gas.

the truck is lifted 3” inches the front and 1.5” inches the back for about 3 years without issue.

I lost my job and I’m doing DoorDash until I find another one, so money is really tight and I need to drive to make more money.

Any idea what it might be? Is it safe to drive?

Thank you in advance, any help is greatly appreciated!

 

I would start by checking all drivetrain fluids. Transmission, T-case and front diff if 4WD, and definitely rear diff.

 

When is the last time you lubed the drivetrain.

 

Lube slip joints and check drive shaft U joints. I haven't seen a U joint go out, but anything can happen. Raise rear tires, put in neutral, wiggle drive shaft or run it while down there observing. I think if joint was bad, it would make noise constantly. There's kinda hard zerks on the transmission drive shaft CV joints. Did you do anything different before it started? Use 4wd? You might try shifting in and out of 4wd.

 

Support the axle on jack stands and put the transfer case in neutral. Spin the rear driveshaft by hand and check for looseness in the U-joints. Check for bent or loose scatter shields (like those on the side of the fuel tank) and loose/bent fuel tank skid plate which may rub on the driveshaft. Check for a bent dust cover behind the pinion flange.

Inspect the two chopstick-sized axle upper links to see either is broken. A broken link will result in more axle wrap when the driveline transitions from loaded to unloaded.

 

Post a video of the noise. Could be a rock in your rotor or anything really

 

I think this is a rear diff issue. But also check and see if you see any seepage of greese or fluid around the shaft areas to see if something looks abnormal. Post pics or a video and someone here Will most likely nail it.

 

You might check rear inner brake pads and parking brake shoes. Mine wears out rear pads twice as fast as front. I would think if it was a bearing or U joint, it would make noise all the time.