30a Internals

Are we talking syncos going or just straight ripping teeth off gears? Syncros failing don't realy count speaking towards the transmissions ability to hold an amount of power. These fail on stock cars with use over time. There are Z32s that have made 1000rwhp on the 30A. For how long? I wouldn't know. But its entirely unfair to judge the strength of the transmission just because you make 400HP and your 3rd or 4th gear synco grinds after 200K miles of abuse.

Which is why my retort to the statement that they are made out of paper, was that the issues are syncro related. I think the 30a syncros are kinda shitty… but my 03 350z totally eating the syncros at 60k with 287HP doing some track days, along with all the thousands of warranty claims and redesigns goes to show that the early trans had a real issue, but it was not strength. So… again. I have tore into the FS6R31A, but not beat on one. I would rate it at as strong as, or slightly less strong as the F/RS5R30A.

Nice, i just realized I have broken and rebuilt them all....

FS5R90A - Stripped input gear teeth on countershaft
FS5W71C - Sheered outputshaft clean in half, stripped all teeth off second gear, twice.
FS5R30A - Broken thrust spacer, allowed counter shaft to walk around and 3rd/4th syncro/hub assembly to fall apart
FS6R31A - Syncros

I'm sure the teeth will go on 3rd in the 30a eventually. Before I took it apart though, my trans shifted like butter and I mean I can't believe it's not butter smooth margarine. We will see what happens. Had some nice pieces of shrapnel fall out when I drained the fluid. Switching to motul 300 from redline should help with trans shock resistance hopefully.

Not sure how much power you plan to put through the 30A, but I'm hitting 24 lbs right now on my 62mm which I'm hoping to be somewhere near or at 500. Well see soon enough. Hopefully my 240K mile 30A holds up. No grinding syncros yet…

If you're worried about strength of the gear sets and other internals in the trans, have them cryo treated and micro-polished.

Plan on seeing this for a few months then upping to over 600 for track days. Good to hear there is someone with real world testing vs. "yeah it should be fine" lol

Synchros are considered consumables in a manual transmission. They will wear out over time regardless. How fast depends on how you treat the trans when shifting, and are critically dependant on the right oil type and correct oil level. Think of synchros as brake pads, as they essentially operate the same way.

Unless tons of customer's brake pads fail early and cause a bunch of warranty claims leading to a redesign, then they are considered faulty : )