2Lucky2tha7

iTrader: (3)

My tranny finally gave out a few hours ago in 1st gear. Sounded and felt pretty nasty!! Tried to move and it was obviously real "clacky" and if I tried to move forward or backwards, it would "catch and try and go in the opposite direction. My guess is that a few teeth sheared off.
Anyway.
I've got a 12A tranny in my garage as well as a 2nd gen NA tranny that was originally in my brother's 350rwhp 1st gen and from what I remember, it started sounding a little noisy before the car was put away. So, I'm a bit weary of that one. The 12A tranny feels more solid, but my question is this: will the 12A tranny hold up to my app. 200rwhp 2nd gen, or will I be replacing it in short order? I honestly don't know how much stronger the internals are in the s4 and s5 trannies as compared to the 12a trannies. I'm dropping the tranny tomorrow morning, so I figured I'd post this up in the meantime while I search around on here. If I don't get any responses, I'll probably go ahead and just put the 12a tranny in. It also looks like I have to swap the tail section as well because of the trans mount casting.
Thanks.

Tom93R1

iTrader: (2)

I am pretty sure the 12a tranny is not going to be a direct bolt in, as well I believe there are some electronics on the 13B that are not on the 12a. I think you are going to be facing a lot of work for this regardless of whether it will take 200hp.

It should hold if you are talking 200HP N/A as there will be much less torque on it than with a turbo.

2Lucky2tha7

iTrader: (3)

Well I got it in last night. Decided to use royal purple 75w-90 to possibly help with durability (maybe). For the most part it involved switching the tail section (the trans. housing, not the internals), as well as the "remote shifter" part along with the rod. The later 13b switches bolt into the newer tail section. I did notice that the 12a shaft is thinner in the mid-sections inside the tranny, the bearings are open and not sealed like the later 13b's, etc.
Since my last tranny broke at 5k in 1st gear, I'm scared to go past 4k now in fear of it breaking. I guess I'll eventually get over it though. My friend pulled me home with his truck the other night, but fortunately it was only about 2 miles away. Next time it might just happen farther away. BTW, when I mentioned 200hp, I meant at the wheels. So, it has me wondering.
...I like the shorter gearing though....

2Lucky2tha7

iTrader: (3)

Well, I got about 8 months out of it. It's rattling badly in neutral now, as well as when it's moving with or without the clutch in. Fortunately I got the car back home before it broke. Time to look for a s5 na trans in good condition and quickly (my dd)

diabolical1

iTrader: (3)

what kind of clutch are you running and how do you drive the car?

i ask simply because if there is something else suspect in terms of use or setup, then you're probably gonna pop the S5 tranny, too.

2Lucky2tha7

iTrader: (3)

Stock pressure plate and disc. When I took out the last (broken) s5 tranny, I noticed that 2 of the marcel springs on the disc were broken and obviously created a problem as well. As for driving the car......well, it's my daily driver. Aside from saying that, the only abuse that ever comes of it is pretty much from WOT runs from 1st -3rd and I can probably count on one hand how many times I've dumped the clutch.

2Lucky2tha7

iTrader: (3)

unless my worn out open diff is creating more shock-loading on the trans.....

diabolical1

iTrader: (3)

wow ... not sure what else to say.

any weird vibrations?

maybe ... broken mirrors? black cats?

2Lucky2tha7

iTrader: (3)

I think that the 12A tranny was just too weak (my guess is that it was a pre- '84), because I was 10x easier on it than I was on my s5 tranny--which lasted over 2 years of lots of WOT 1st - 3rd gear driving, etc. This makes sense because my 1st gear blew out.

diabolical1

iTrader: (3)

what about lubricant? what do you use?

have you considered getting a T2 tranny? i don't know, it sounds like you've managed to increase torque significantly over stock. perhaps that's just the long and short of it. maybe so ...


on a sidenote, i'm not sure i'd just condemn the earlier trannies for two reasons:

1. i think the 5-speeds from the FBs to FCs are essentially the same - a few minor differences aside, and

2. i've never seemed to make any rhyme or reason out of why the damn things give up (other than all out abuse or hard lives with turbo engines ahead of them). i've seen them last years with drag race use behind bridgeys and nitrous. back in '97 my own personal tranny quit after roughly 4 years of hard use, but it was 5th and reverse that died, while first through fourth made horrible noises. i would have expected it to have been first, second, or third to die based on how i used it.

that said, i know my opinion does nothing to help you figure out your issues and i also realize that there's really no need to put one of the older NA trannies in your car. wish i could have helped more and if i get any ideas, i'll be sure to throw them your way.

2Lucky2tha7

iTrader: (3)

The only reason I used it (even though I really didn't want to), is because I didn't have the time to wait and find another tranny to buy, so I pulled the tranny out the day after it broke and put the 12A tranny in that I had in the garage. Also, my 4-port setup does make more torque than my last 6-port setup, so that might have something to do with it, even though it's no bridge, etc.