[user removed]

Yeah I didn't do very well with my instructions.

Engine off
Clutch disengaged

Start in 5th and downshift thought the gears to 1st and you slow down, 5,4,3,2,1.

Engine off eliminates the clutch since it is stationary, also the throwout bearing which is stationary when the engine is not rotating.

The transmission has three operational sections. Imput, gear selection. and output-final drive.

Coast down in neutral to test the final drive, noise should become less linerarly and consistently (thats differential output shaft)-carrier bearings.

If the noise becomes much greater as you downshift then it's most likely the input shaft bearing. The highest bearings in the case as well as the one subjected to the greatest sustained loads are your prime suspects unless the test shows differently.

We always replaced all the bearings, and shaft seals, when we went into a transmission. You can check OE prices versus aftermarket, but I would never put cheap Chinese junk in something that was that labor intensive. NSK is a good brand of quality bearing and you may save a good amount of money if you have a locally owned bearing supplier who is reasonable for prices.

Don't let it go too far, I had one transmission come apart 50 feet from the shop on the diagnostic test drive. Fortunately we had plenty of scrap transmissions for parts.

MY doctor was a customer when he was in medical school, he came in one day in his hardbody truck and it would only move in 4th gear. We pulled the transmission down and it looked perfect. After some more checking we found out the input shaft gear had sheared the key off, which meant only foruth gear worked because that gear was actually when the input shaft was directly connected to the output shaft. Of course that RWD Nissan transmission is very different from Honda FWD transmission.

regards
Mech