Decided to rebuild the transmission

[grannyknot]

My close ratio 5spd seems to work perfectly except for this very loud rattling/ringing in 2nd,3rd,4th and 5th.

I can quiet it down a bit if I hold onto the stick shift all the time, it's driving me nuts, so I've started tearing it down. My Haynes manual is mostly useless but found these great vids on youtube that show the entire tear down and rebuild, they are on post #5 on this thread,http://www.classiczcars.com/forums/engine-drivetrain-s30/45179-rebuild-transmission-tool-harber-freight-6-ton-frame-bench-shop-press.html

I love the archives! Here are some pics so far, I know the shop is a mess but everything still has to go in the parts washer before reassembly,

Can I just use engine assembly lube to put it back together or should I use tranny oil?

[Zed Head]

Did you find any reason for the noise? And where did you get your parts?

There is a very good thread over on Hybridz from a guy who wanted to build his transmission for high RPM shifts, racing style. He really knew what he was doing and discovered some interesting things about synchro gear options, and how to modify the the synchros so that they work perfectly. If you're in to perfecting your parts I can dig it up and post the link.

On the synchros topic - they're designed to work with specific gear oil qualities. Oil film strength and viscosity are key. I wouldn't want any foreign materials in there at all.

[EuroDat]

Hi Chris,

I went through a similar situation with my close ratio 71B. All gears were noisy, except 4th. I changed the bearings and some needle bearings. It did reduce the noise, but its still there and that is with using a quality Red-Line tranny oil.

A note about oil. Make sure its suitable for brass synchro rings (without sulphur). Red-line make two varieties of transmission oil in different grades. The GL-5 with sulphur and the MT85 and MT90 for older transmissions with brass synchros.

My problem is in the gears and the bearing surface in the gears, see first photo red circle. The dull area on the bearing surface for fifth. It might of had the wrong oil or too little in the past.

I found some photo's of the bearings and a photo of all the seals. The seals are still available through Nissan.

Chas

[grannyknot]

Zed, that's just it, so far I haven't come across anything really worn or loose, bearings are in good shape.

This the place I bought the rebuild kit from,Nissian 4 and 5 speed FS5W71 Manual transmission Rebuild kit parts | FS5W71C overhaul kits - Drivetrain.com I believe I ordered DTS-BK104WS

If you could find a link to that thread I would appreciate it.

Chas, I have been using Redline MTL 75/90FS which is their stuff for trannys with yellow metal.

Did you order your needle bearings from Nissan?

[ajmcforester]

That transmission looks good from the picture maybe the linkages is the problem? Do they seam firm?

[Zed Head]

Here it is. You have to read the whole thing, a lot of learning happened along the way.

High RPM shifting dynamics - Drivetrain - HybridZ

[tlorber]

Good for you, for rebuilding it. I was always intimidated (due to the exploded diagrams) and then about 3 years ago I rebuilt the same tranny (bearings were shot). You may as well use everything that came with the kit. I bought mine from the same place. Seals, baulk rings and bearings all go out given enough mileage.

2 tips if I might; 1) use wooden dowels to place the gears and ring on so that they all stay in the same order; 2) the kit did NOT come with a new O ring that goes on the sleeve that the shift lever goes into so I just used the old one. I get a slight bit of oil seepage past this ring.

[ph240]

I'm rebuilding my 280Z 5 speed and will REM the gears and shafts. I'll post once it's done. I'm having trouble locating the 5th gear synchro. Anyone know who may have it ?

[EuroDat]

Chris, That kit is for the 71C transmission. It is the same except for the front bearing on the cluster gears. Its larger than the one in the 71B. They don't make the 71B kit anymore or so I was told by drivetrain when I called them about it. I ended up getting them locally.

The needel bearings wear available at my local Nissan, but he had to search for some.

The bottom row (ball bearings) are the difference in the kits.

The neddle roller bearing is for input and main shaft. It also fits the reverse gear, but it doesn't suffer as much and probablt won't need replacing.

The needle roller bearing is what make it hard to get the noise down to "as new" levels. If they are worn, so is the surface in the gears and then its just too expansive to fix.

Chas

Edited January 20, 2014 by EuroDat

[beermanpete]

Can I just use engine assembly lube to put it back together or should I use tranny oil?

While preparing to rebuild the 4-speed transmission for our Z I found a suggestion to use grease with a low melting point so the grease will dissolve into the gear oil easily. As a result I used an automatic transmission assembly lube that I bought from Summit.

http://www.summitracing.com/parts/sum-705050/overview/

[grannyknot]

Zed, what a fantastic thread that is! Lots of good details to be learned from it. You gotta love a poster that shows you all the warts of the procedure as well as the progress. After reading all 9 pages and seeing all of Duragg's photo's I can say my transmission is in very good condition compared to his and not abused.

Good for you, for rebuilding it. I was always intimidated (due to the exploded diagrams) and then about 3 years ago I rebuilt the same tranny (bearings were shot). You may as well use everything that came with the kit. I bought mine from the same place. Seals, baulk rings and bearings all go out given enough mileage.

2 tips if I might; 1) use wooden dowels to place the gears and ring on so that they all stay in the same order; 2) the kit did NOT come with a new O ring that goes on the sleeve that the shift lever goes into so I just used the old one. I get a slight bit of oil seepage past this ring.

I was hesitant too but a rebulid around here is $1,300-1,500.00, so that's what convinced me. I was surprised when I opened the kit, I thought it was missing a lot of things, that shifter rod seal you mentioned the O ring just rear of it, all the individual ball bearings, springs for the syncro keys.

Chris, That kit is for the 71C transmission. It is the same except for the front bearing on the cluster gears. Its larger than the one in the 71B. They don't make the 71B kit anymore or so I was told by drivetrain when I called them about it. I ended up getting them locally.

The needel bearings wear available at my local Nissan, but he had to search for some.

The bottom row (ball bearings) are the difference in the kits.

The neddle roller bearing is for input and main shaft. It also fits the reverse gear, but it doesn't suffer as much and probablt won't need replacing.

The needle roller bearing is what make it hard to get the noise down to "as new" levels. If they are worn, so is the surface in the gears and then its just too expansive to fix.

Chas

Chas, that kit I ordered fits my 1983 ZX trans perfectly, I have checked all bearings and they are identical as well as the brass 5th gear syncro ring.

Are you saying you think the high pitched rattling/ ringing sound (the reason I'm overhauling in the first place)is the 6 big needle bearings? I hope not, those are going to be expensive. They are in very good condition with no visible wear on the bearing or shaft.

While preparing to rebuild the 4-speed transmission for our Z I found a suggestion to use grease with a low melting point so the grease will dissolve into the gear oil easily. As a result I used an automatic transmission assembly lube that I bought from Summit.

http://www.summitracing.com/parts/sum-705050/overview/

Pete, I went up to my local transmission shop and p/u a tub of tranny assembly lube, now I have enough for 20 rebuilds.

The first pic is the cone on 5th gear, you can see it is glazed with a bit of metal transfer on the surface.

The second pic is after hand buffing with new 3M Scotchbrite (rouge) now there is a nice neutral surface for the new syncro ring to bed in to. I'm not going to lap them together as 5-10 miles of easy driving will do the same thing.

NO, it's not a telescope,

try as I might I could not find a 38mm Crowfoot wrench for the main output shaft nut so cut up my 38mm shallow socket and welded 13" of thick walled pipe in between so I can torque that nut properly.

[EuroDat]

I was hesitant too but a rebulid around here is $1,300-1,500.00, so that's what convinced me. I was surprised when I opened the kit, I thought it was missing a lot of things, that shifter rod seal you mentioned the O ring just rear of it, all the individual ball bearings, springs for the syncro keys.

Chas, that kit I ordered fits my 1983 ZX trans perfectly, I have checked all bearings and they are identical as well as the brass 5th gear syncro ring.

Are you saying you think the high pitched rattling/ ringing sound (the reason I'm overhauling in the first place)is the 6 big needle bearings? I hope not, those are going to be expensive. They are in very good condition with no visible wear on the bearing or shaft.

Chris

Your problem is probably a little different to mine. Mine has a whine noise which is typical of worn bearings. Thats why I posted a photo with the dull surface area on the shaft sleeve. If you have to start replacing that stuff, it gets too expensive and IMO better to buy a new 71C for around $1700 and do the 71C swap.

I have all the part numbers for the o-rings, lip seals, nuts and oil gutter if you need them. They are all available through Nissan and dont cost much. From memory about $40 for all the loose parts including the shifter bushing kit.

Goodluck with the rebuild.

Chas