Siren_

Let me begin by saying I'm not the most trans-savvy person. So I apologize in advance. I'm stuck though. Skip to TL;DR if you don't feel like reading.

B-Series Hydro trans with LSD. Not entirely sure what trans it is... it was already in the car when I got it and the previous owner still swears up and down that it's a Type R transmission. It's either a B16 with LSD or it's an S4C (both rev like a B16, which this one does). Apparently The S4C trans are quite rare and have dual synchros in 2nd, 3rd, and 4th as well as LSD.

I've just been dailying the car, only problem I ever encountered was the occasional grind during higher RPM 1>2 shifts. Later, I started getting vibrations, not a big surprise. Turns out one of the springs popped out of the stock clutch so she got a brand new Competition stage 4 clutch, Comp 11.5lb Flywheel, and a Comp HD PP. When all that went in, so did some GM Synchromesh fluid (to make nice with that occasional grind). Good news is, she has a functioning clutch now, bad news is. she keeps locking and popping me out of gear!

The car drives just fine when shifting 1>2>3>4>5. But say you're coasting in N and would like to rev it up and throw it in 2nd to turn onto a street. Locked out.

2nd gear lockout continued like that for a while, I figured the GM SM just made my 2nd synchro worse. It locked out during downshifts as well. 2nd is also known for popping out of gear during those slow traffic rolls during rush hours. It stays in the second gear spot without grinding but the car just starts revving. Sometimes it'll stop locking and let me into 2nd just to be met with a bad grind. Conclusion, second synchro(s?) = shot.

Recently, 2nd has come back (8 times out of ten/ N>2 & 3>2) and 3rd has started locking me out. I know this is bad, but if you just punch it in, it goes, otherwise I just skip it. but I have never ever experienced a grind with 3rd gear, ever.

I'm going to go put this (thick) Blue synthetic Redline stuff back in it next week (it was in there before) and see what happens. After searching all of Google and HT and reading some other people's problems, I'm beginning to think the synchros might be more of a symptom and less of the problem.

Thoughts? Sorry I wrote a book.


TransIdoiot Question 1: Does dual synchros literally mean 2 synchros. Or a special sort of single synchro?

TL;DR: Bseries trans shifts 1>2>3>4>5. But locks out during N>2/3>2. 2nd came back (mostly) and 3 is locking out when N>3.

ArniFPR

just tear it open and see if there are loose bolts or something, my friend had a similar problem and one of the bolt that holds the shift linkage.

94EG8

S4C is a B16 trans. Some JDM models have a 14 bolt viscous LSD, they're very easily identified once the case is open. Type R will have a helical LSD, larger ring gear and it will be 10 bolt. The gearing is the same (other than '98+ JDM ITR) All B-series trans, except LS have a dual cone synchro on 2nd gear only.

It's basically a synchro, a cone, and then another synchro all sandwiched together to give you more surface area, it's similar in that respect to a twin disc clutch.

Pic of what a dual cone synchro looks like.



Regardless of what trans you have, it needs to come apart. I would suggest you take it apart and see what you have and what it needs, then order accordingly or replace the unit if it's not cost effective to repair.

Siren_

Thanks, guys. Thanks for the clarification 94EG8. Should be out and apart in a few months.