Alright this is an odd one, I've been searching around, asking questions and nobody seems to have a clue. There are two issues here that are concerning me about the transmission in my 2002 DX.


1. At launch (not every time and only when pushing it hard) first gear makes a loud whine that will continue into second as-long-as I stay into the throttle. This 'whine' sounds similar to reverse but its louder are far more intense. It's done this for a long time, again only when under heavy load, only about 20-30% of the time and only when the clutch is engaged(foot off the pedal).

FYI I've replaced the clutch, throw out, pilot bearings, and the engine(spun bearing) since this noise started.


2. Now for the one that's ticking me off. Second, third and forth gear pop 'halfway' out under light driving conditions. They don't seem to ever pop out under load more just while maintaining cruising speeds. Second doesn't do it too often but when it does its usually during a left turn at 5-10MPH during light deceleration. Third and forth gear seem to do it at about the same time. When cruising at between 30-40MPH in third or forth with little to no throttle it will pop out of gear. When it pops out of gear its only coming out halfway so you will hear a very slight gear grinding. I can disengage the clutch, put it right back into gear and it will do it three to four more times in a row then be fine again for 10-15 miles. I have found that when it comes out of gear I can(without touching the clutch) give the engine a slight rev and it will drop right back into gear as if i was compression shifting. It only started doing this after replacing the engine, clutch, throw out and pilot.

To say the least, I'm miffed...

BTW, running Redline MTL in the transmission, started using it because of the gear popping out.

A little back story:
The car is almost completely stock, the motor was replaced because it spun a bearing during my commute home one day. I replaced the clutch and bearing at the same time as the engine in hopes that it would address the whine, there was still a lot of material left on the old clutch. When I bought the car used I had known that I would be replacing the motor at one point or another because the previous owner hadn't changed the oil in the three years she had owned it and the pan only had about a half a quart of sludgy oil. I picked the car up for a really good deal to say the least and had an extra D17A1 sitting in the garage. Incredible motor by the way, I put 30,000 miles on it before it spun the bearing and that's a long time for an engine that's been run out of oil.

I love this car, it's been the most efficient commuter I've ever owned.

 

Popping out of gear can be because of bad motor mounts let the engine move too far and pull on the shift linkage under certain conditions. Or it's bent stuff inside the transmission. The D-series manual has a weak point in the outside input shaft bearing, it will wear out faster than other parts in the unit. If you're hearing bearing noise idling in neutral (that goes away with the clutch pushed down) it's probably that. You can replace the bearing rather simply without taking the transmission completely apart. Or since you're hearing other noises and maybe not staying in gear, swap in a used transmission.