Engine Rattle - Help!

[tmaull]

My car has started making a god awful rattle. It’s either a harmonic with the engine or in the engine itself.

Characteristics
- Rattle occurs at approx 2800-4500 under moderate load, most audible in third and fourth gears
- Completely goes away when I declutch
- Is inaudible when I shift to fifth at highway speed

Other info
- Engine rebuilt approx 3000 miles ago
- Only recent change was the installation of a wevo shifter and psj

I’ve uploaded a YouTube video, although it doesn’t quite do the rattle justice.

https://youtu.be/lqLhP2GNNYc

Thanks all, can’t wait to get this solved.
-t

[garment]

I replaced the engine and tranny mounts on my SC a few years back. Started to see some rubbery crumbs at the motor mounts, thought “that’s funny” but then looked a bit closer and found the new bushings had almost completely disintegrated, after only a few seasons. Check your mounts. You’ll get shifting improvements as well if you replace.

[tmaull]

Any procedures y'all would recommend in terms of isolating the noise? My forum searching didn't come up with much. It didn't seem consistent with chain tensioner collapse.

[yelcab1]

If it rattles when you are driving and goes away on you press on the clutch, it is in your gearbox.

[tmaull]

Okay so right now my checklist looks like:
Engine and transmission mounts
Engine tins
Half shafts

[tmaull]

So bringing this full circle. Welp - finally fixed it. Noticed that it was only happening in 3rd and 4th. Noticed if i held the shifter over to the left it’d stop. Messed around with the shift coupler for a good bit until it was gone. Got some trans mounts I’ll throw in eventually as well.