rickyhils

Then I am easy on the drive train due to my habits. I'll check the 90w gear oil in the currently running car. It was fresh 12 years and 150k miles ago. I could drain the gear oil and inspect it for debris. FWIW- If I were an STI owner [with MT5?] and wanted to invest in new synchros, [for max performance] I wonder how much four new synchros would be, if available. That would be just the parts only. And - I also drive a 1997 Honda Accord w/ 5spd man trans, and the 2nd gear synchro has been out for a long time now. I usually accelerate more in 1st and then go directly to 3rd. It uses 30w motor oil. Hondas are known for weak synchros.

My running 1991 Loyale has 326k on it . It has never been driven rough. It will always have 90w gear oil in the trans.

So, do synchros wear out faster with heavy acceleration?

Thanks GD . I can get the large rear bearing pressed off sure enough. Both bearings will be replaced anyway. (middle bearing just slides off the front of the shaft) . Then it's a matter of keeping my wits in getting the gears off and back on ok. Need to first research availability and price of any needed synchros. Very likely that synchros are still good , as currently running 1991 Loyale is at 326k and MT5 tranny is good.

I have been learning more about synchros. Do I have this right? They are individual clutches that freely spin at engine speed before being pushed over to mesh and then the clutch surfaces make contact, all within a split second. On the Subaru, are the synchro clutch surfaces "tapered mating surfaces" or are they "flat" and just butt up against each other? I think they might have a tapered "inner and outer" clutch surface, and that would explain why they cannot be viewed unless removed. A smooth clutch surface would not push away enough of the oil and grip well enough.

All good info there. Thanks.

I can lift out the mainshaft easy enough. If I slide the gears can I then see the friction cones? I guess that I am looking for smooth surfaces that are not "chewed" up? And I now see how that reverse lockout forces you to go from 5th to neutral before going into reverse. That is so clever. And that is exactly why I would sometimes think that I had meshing problems when going into reverse. Thanks a bunch. Ricky

I have a salvage yard MT5 FWD tranny that I am accessing to have as a backup. My 1991 Loyale runs ok. But 13 years and 150k miles ago, I saw "Gloyale" post how to split the tranny case halves. In 2008 I had exactly ZERO experience with any Subaru, but I was forced into it. With leaking (very messy) front mainshaft oil seal and vibrating mainshaft, it was either fix it myself or junk the car. I put in SUBARU (NOK) seal and two new mainshaft bearings. So, I sort of know a bit about that tranny. Pics here of the synchros. I think they look ok. And ANYONE, what is that "lockout" device opposite the shift arm? (See pic) Edit: I'm guessing it is a reverse lockout when car is moving forward. Farthest out (larger of the two) bearing has enough play to feel by hand. Just the tiniest bit of play, but it would be STUPID to not change both bearings along with the front and rear seals. And the two output shafts have seals. The smaller bearing is a IKO G TR224220E03. Subaru parts dept is iffy for me, as when the Loyale came out, there were more than one supplier for the trannys. I can't see the larger bearing number, as It needs to be pressed off first. The output shafts have the slightest play at the pinion gear. At least I know enough NOT to mess with them! Better to have a bit of play then to muck things up trying to turn that outer plate and burning it out by being too tight. HOWEVER, I admit that in 2008 I brought them in by one cog (and one cog step only) which is about 5 or 10 degrees worth of inward mov't. But no problems so far after 150k miles. And, back in 2008 I had enough "beginners luck" to remember to put sealant on the case halves before putting it back in the car! And I knew about the dowel pin at the smaller bearing. Point being that with some experience can cause one to become overconfident and that can be where stupid mistakes happen.

Without TB covers can swap out just the worn belts and then keep tabs on the tensioners and idler. I once had a cheap set of ITM (Chinese knockoff) TBs and one belt would wander back n forth across the cam gear. I think I now have Mitsuboshi belts.

Thx for the good info. And YES. The oil pump has that sprocket lip.

idosubaru I run no front TB covers on 1991 Loyale. So, can just as well leave back covers off?

My 1991 Loyale FWD 5 spd SPFI has the CEL for EGR code #34 coming on. Wiring is ok from ECU box to blu/red wire at EGR solenoid. Both wires ok. Solenoid reads 45 ohms. With ignition ON/engine OFF the reference voltage at EGR solenoid reads 12 volts. Ground is ok at ECU case and at the wire harness to engine block. Some history - Two years ago I changed out the EGR solenoid when code #34 showed up. Still CEL on. After wiring path checked ok I changed out the UPA1478H transistor array chip inside the ECU box and all was ok for a few months until the code #34 showed up again and I again swapped out that same chip. I even used a 35 ohm dummy load resistor in case that the EGR solenoid winding inductance was causing voltage spikes to fry the chip. All good once again. But later CEL w code #34 showed up again. CEL comes on and then goes off by itself after some driving. Always code #34 . All wires ok. So when CEL on I disconnected the battery for a minute or so and then restarted the car. ECU then gave no code for EGR even after raising RPM to activate the EGR. ECU acts like nothing was ever wrong. I even tested by unplugging EGR- and CEL went on. Then when plugging back in CEL went off. Am aware that revving the engine was needed to trigger any EGR code #34. For now no CEL. * So, could this be a possible interaction or contra-indication from the RPM sensing circuit? Maybe just a design flaw?

THanks

And I suppose that on a smaller scale, even the EGR solenoid can cause voltage spikes when it lets off. That's why I wired in a dummy resistor load instead of the EGR solenoid.

I looked up what inductance is. Yeah, the solenoid winding and the magnet at the starter motor will cause a huge amperage load. That amp load probably backs off a bit after gear is engaged and spinning. There must be a high amp connector inside that clamps closed to actually spin the motor. Like on my Honda. But to operate the moving solenoid is enough reason to add a relay.