EG D series Si tranny problem

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JDMBoOsT

New Member
I have a d15b with the Si tranny I just baught, im just wondering whats wrong with it and figured some on here would know. First thing no matter what i do going from 2end to third grinds. If i go from 4th to third it don't. Also going from 1st to 2end is fine but if I am to downshift from third or whatever It wont go into 2end I have to crame it in there. Im trinking the shift forks might be bent but I don't know. Any info would be great! Thanks guys
 
It's rare for synchros to go bad; but it would be consistant. <95 tranmsissions are more likely to snap shift forks(they're aluminum vs. the steel 96-00 ones). Only way to check is to open it up. Also, there could be issues with the bearings working loose(pretty common on D-series).

Start with the easy one first(rear torque mount), and work your way up.
 
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I know the throw-out bearing, pilot bearing, and clutch are all good. I replaced all when I put the tranny in the other night. I was told it was an si tranny but the stamp on the case says P20 A000, but the gears are ALOT shorter than my old one and I can tell a big difference. Is it possible someone might have put Si gears in this case? or would that be stupid and out of question. Any info would be great.
 
I would just rebuild it, or you could just replace the syncros and just look at the 2nd gear to see. I've seen this before, some ricer misses a gear and grinds the sh** out if it. Also your shift linkage could be hitting in 2nd gear, lift the car up and have someone shift while you look at it, or does it shift okay when it's just sitting, not driving. Last it could just be the engine mounts, it could cause you to not be able to get into 2nd right. Just try these things and it might be something simple. Isn't s20 the EX transmission? I think the EX and Si have the same gear-ratios, and final drive.
 
Syncros for sure. I had the same transmission (if you have an EG its the D16Z6 trans.

My syncros for 3rd went out too.

You can try to rebuild (been told many times that its a hassle)

Or....do what I did and go buy a used one from a recycler for $300-500

But you have to install it and see if it works (if it doesn't....they'll exchange but you get to install again)
 
Rebuilding can be hard, but it's the cheapest way. A shop charges $200-$300 for a rebuild.
 
It probaly needs more than just syncros when a syncro goes bad it causes gear clash with the slider. A gear has engagemanet teeth that should look like this /\ but when you grind the gears you are wearing the engagement teeth off and causing them to look like this \ or -- and then the slider has trouble going over it. If you dont know any thing about a transmisson you have know business opening it up and just throwing syncros at it. Its no diffrent than building a engine there are specific tolerances and things to check that should never be over looked.

look at this pic this guy replaced the syncro but the teeth on the gear and slider are in bad shape and thes also should have been replaced
Picture041.jpg

gear.jpg

sleeve.jpg
 
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