So I just got an EF with an LS swap and hydro trans. It makes some strange sounds I haven't found the sources for.
1. Under throttle, I get a faint sound almost like someone thumbing through a deck of cards quickly. Like a steady patter. I suspect the throwout bearing.
2. When I let off the gas, especially downhill, I get a sound of metal on metal, not quite grinding. But like a shhhhhhhhh sound. If I push or pull on the shifter, it'll change, either going away, or turning into a faint gear grind "dzzzzz" sound. Only present on deceleration, and it only happens some times. Especially in fifth and fourth, but in third sometimes as well. Throwout bearing, synchros, or diff are my suspects.
The shifter has the worst slop I've ever felt BTW, just for more info.

 

The patter sound under throttle could be an internal bearing or pilot bearing. Throwout bearing makes noise only when the clutch is disengaged. The other sound is a bearing.

 

Really? I've had throwout bearings whine in gear, went away when replaced. And by internal bearings you mean like main/counter shaft case bearings? You think some dog teeth and synchros are probably trashed too? I know the fourth synchro is on its way, it kind of crunches into gear. I was unsure of the bearings because it turns into a signature gear grind sound, but I feel like I've seen you post some good info in the trans forums.

 

Yes, main or counter bearings most likely. If it grinds or scrapes that could be related if one of the bearings is really out (usually the top CSB).

 

Perfect, thanks man, I really appreciate the info. I'll drop the trans when I'm prepared to buy a new one, and I'll post pics when the culprits are discovered. I found a good rebuild guide so if the gearsets look okay I'll try my hand at a rebuild. Has synchrotech figured out their delamination issues as far as you're aware?

 

The delamination issues are no longer a problem with their current synchros.