Grinding sound w\ new transmission

[Shakey]

Replaced my "260" transmission out of my '72 and replaced with an "82 zx 5-speed. While out of the car I had a new clutch, disk and bearing ready to put in, but found the current set-up (Nissan OEM) was in almost new shape so I kept the clutch parts from the 260 in the car. The only different part was the clutch fork which was replaced with the fork from the 5-speed. Had taken the 5-speed gears out of the tranny housing for a visual inspection and found nothing wrong visually. Put back together and added 1 and half qt. of Red Line MT-90. Now the problem. The car runs through all 5 gears fine but there is a grinding sound. It is more apparent when you come to a rolling stop but that is probally because at higher speeds the sound is either deadened or that faster moving parts don't sound as rough. Anyway, the sound is there whether the clutch is engaged or not and the car is in gear. The sound is there when the car is in gear but not if the gears are in nutaral. The sound is also present in reverse. Have adjusted the slave as best I could. Replaced the fluid in the master and bled. It also seems that this is causing a drag on the cars ability to roll, as up to a stop sign. I did detect a burning ordor the first time I took it for a test drive. Would appreciate any suggestions. Thanks.

[The Wingnut]

Shakey, is it a constant whine of some sort?

I have a similar setup in my '74 260...stock motor, swapped-in 5-speed. I was told that the slight whine / grind that I was hearing with the clutch out was because of the throwout bearing, possibly because it was installed backward.

The trasmission has ove the past 4 months become harder to shift, to the point of being quite difficult. The car now creeps a bit while in gear and with the clutch in.

[seerex]

I would have to say thats big possibility , if the throw out bearing was bad it would make a humming if the car was in neutral atleast thats the expierence I have had, I could be wrong about this but I don't ever recall switching clutch forks when putting in the 5 speed tranny, sounds like the car is engaged partially <in gear>weither the clutch depressed or not , I did have this issue before in a car and it was not the tranny or clutch but another part incorrectly installed

[Shakey]

Thanks for the response about my tranny problem. Since my original post I began to question if the amount of fluid was adequite. I originally followed my Haynes book and the correct fluid for a 260 5-speed (did not have specs for a 280zx) and put in one and half quarts. Jacked up the car and added what I thought would be another quarter to a half qt. Ended up taking the entire quart. Have had the car out for a 30 mile trip and still expierence an occasional grinding sound when I slow down for a stop and the car still in gear. Grinding seems to go away when I engage the clutch. Have since put the car away for the winter so don't have alot of driving experince to totally get the feel on exactly when the grind starts and how to stop it. Do think that the additional fluid did help alot.

It is interesting about the possibility of the throwout being installed backwards. Will have to check this out if the tranny needs to be pulled. Thanks alot.

[Ed]

Not exactly sure how much oil a tranny takes but your supposed to fill it until it flows out of the fill hole or starts to overflow. If you change the fluid all together then inspect the drain plug. It has a magnet attached to it and will have metal shavings attached to it if you have an internal problem.

[satelles]

I fairly certain that I have the exact same grinding sound. It happens when the engine is between 2000 and 2500 RPM in 3rd or 4th gear, clutch in or out, basically when I'm coasting at about 45-50MPH. It started happening after I installed a NOS 3.91 differential! I've replaced the wheel bearings, all diff mounts and bushings, including the mustache bar bushings. I also have the dreaded rear end clunk happening when quickly letting out the clutch. Could it be something rattling in the half shafts? I also suspect a rattling exhast pipe, but I'm not sure....

[Shakey]

Satelles, That interesting about the different dif. you put in. I also replaced my old one with a 4.11 and kept with my old half shafts. Did drive the car about a month before the tranny change just to know that the changed out part worked well before changing the other. Did not have any problem other than there seems to be somewhat more rear end noise. Nothing that was not expected from what other posts have said. My grind sound is present when I'm about to come to a stop. Hoping that next spring when it comes out that the noise goes away.

Ed, I did check the drain plug when I first purchased it and although there was no fluid in the case there was no signs of metal or anywhere inside when I opened it up.

[Zedrally]

This could be caused by the universals on the tail shaft.

I replaced one, got rid of the clunk and now have a grinding noise from 40-65kmh. The other [uni] was line ball, but I know replacing it will solve the problem.

HIH

MOM