I have three Sentras. This is my oldest. It has 104K miles and it generally looks and runs like new. But when I go over bumps, it rattles in either the engine compartment or underneath. It’s been this way for a few years and it’s not getting any better or worse. I’ve heard it could be the subframe(?). Does that make sense? The dealer says it will be about $1,700 to replace the subframe, if that’s the problem.

Is it rattling mostly over 2-wheel bumps (like speed bumps) or 1-wheel bumps (like potholes) and turns? If it's the former then it may be subframe bushings, a lower torque mount, or just something loose in the undercarriage. If it's the latter then it's most likely sway bar bushings, links, or a bad (shifted) bar. Do you have any signs of uneven tire wear? If so it may be a control arm or ball joint.

VStar650CL wrote: ↑

Fri Apr 30, 2021 7:00 pm

Is it rattling mostly over 2-wheel bumps (like speed bumps) or 1-wheel bumps (like potholes) and turns? If it's the former then it may be subframe bushings, a lower torque mount, or just something loose in the undercarriage. If it's the latter then it's most likely sway bar bushings, links, or a bad (shifted) bar. Do you have any signs of uneven tire wear? If so it may be a control arm or ball joint.

The shocks, struts, and lower control arms were replaced at 92K miles. Turning doesn’t cause the noise. Going over any bump (large or small) will cause the noise. It’s like a tinny jingling. It’s not the heat shield or the transmission mounts (just replaced).

If it's tinny and it isn't a heat shield, rap on the catalyst with a deadblow hammer and make sure it isn't cracking internally. Also, if the flex-pipe shields are tack-welded, pry on them and make sure there aren't broken welds. It's very common for those to look fine even though they're busted.

VStar650CL wrote: ↑

Fri Apr 30, 2021 8:29 pm

If it's tinny and it isn't a heat shield, rap on the catalyst with a deadblow hammer and make sure it isn't cracking internally. Also, if the flex-pipe shields are tack-welded, pry on them and make sure there aren't broken welds. It's very common for those to look fine even though they're busted.

Thank you!

Maybe the exhaust is hitting something.

I don't get a rattle on my subframe it's more a squeak. When I had the rattle i believe it was my strut mounts. Which I replaced a month ago and no more rattle.