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Starting a new project...Subaru STI Differential swap into my Z


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I have not opened it but I would think it was the smaller size. The car was an '88 turbo s12 with 4.11 R200.

I have an early type out of a 300ZX with 68k km on it. Planning on swapping the 71b in my car. Unfortunatly the 71b came from a 280ZX with unknown milage. Even with a new set of bearings and synchro rings its noisy.

Chas

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Bummer that the 71B rebuild didn't work out. Apparently they're not easy to get back to factory-level performance with the parts that are available for rebuilding.

What kind of noise does the 71B make? Shifting, driving or just sitting in neutral? I have a late ZX 5 speed in my car now that needs synchros, and a 1985 300ZX 71C with the front case swap completed ready to replace it. I'd like to take a shot at rebuilding the 71B but there's only one person who seems to have really improved his 71B, and been happy with it, with a rebuild and that's duragg over on Hybridz.org. And he spent a lot of money on Nissan parts, and a lot of time on fitting the synchros perfectly to the gears.

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I used bearings from a local supplier, synchros, needle rollers, gaskets/seals and the shaft nuts from my local Nissan dealer.

Most of those parts are the same as the 71C part numbers and still available at Nissan.

I don't like using the kits because the supplier couldnt tell me the manufacturer of the bearings and the kit is only the ball bearings and gaskets.

The transmission had a growling whine in all the gears except 4th. This I thought was typical bearing noise caused by sideways force when the gears are under load. I suspected a shot bearing in the cluster shaft.

After the rebuild everything worked very nicely, but the whine is still there and 5th is marginally the worst. The bearing "kit" and Red-line trans oil helped it a lot, but its dissapointing that the whine hasn't gone.

I noticed the gear teeth were dull and not very shiny like the ones in the 300Zx 71C transmission I have. I think the 71B was run with a low oil level or the wrong oil?

I would like to do the 71C swap, but other things are keeping me occupied atm.

Zedyone, Sorry for hi-jacking your thread, but it might help you with your tranny swap. I want to start a new thread on my 71C project. Hopefully start it in Feburary.

Chas

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no worries. Both my original 71 Type A transmission and my new late 71 Type B transmission have a third gear whine. I just think that it is something about 3rd gear. It will be nice to have a 5 speed, but I am not looking forward to pulling the engine AGAIN! I have had poor luck installing a transmission with the engine in the car.

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If it didn't whine in 5th, I would probably put up with it, but then I would be the one "whining" about it to the wifeLOL

What was causing you so much grief removing the transmission? Removing the engine, I can understand you not wanting to do that again in a hurry.

I have done mine with virtually no problems. I removed the top radiator hose, heater hose, air intake hose and throttle linkage just to be sure I wouldnt damaged anything.

Can't tilt the engine much anyway with the fan shroud in place. Still had enough room to drop it out by myself and that is with the 280ZX 2+2 clutch.

Chas

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I struggled to mate the current transmission to the engine for 2 days of ramming it forward and pulling it back. It just never lined up. I made some long studs to help guide it in. Nope. I finally gave up and pulled the engine and put it on a wooden stand and then slid the transmission while on a transmission jack to the engine, and it was still hard. I am not sure why. These things should just align and go in. But who knows why it gave me such greif. If I could get the car up higher it would not be an issue I think. It may be time to buy a big boy jack.

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If the clutch disc is not perfectly centered the nose of the main shaft will sometimes not slide easily in to the pilot bushing. That's the last part, along with the dowels in the engine block, that mate when installing. I've had loose, poor quality clutch alignment tools that would let the disc drop down when tightening the pressure plate. You need the tightest alignment tool you can get, and hold it up perpendicular with the back of the engine while tightening the plate bolts. Spend a lot of time getting that perfect before lifting the transmission up.

I've also found that the scissor jack that comes with the cars is great for holding up the back of the engine. You can adjust the angle of the engine on-the-fly as you get everything aligned. Sometimes it's easier to adjust the engine than the transmission.

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Im thinking also along the same line as Zed Head. Clutch disc maybe not exactly in line or the angle was a little bit off.

I have nether used an aligning tool. Nissan sells the clutch components individually and I nether bothered to order one. Just eyed it up with the pressure plate tightened enough to hold the disc in place and used a loose fitting dowel rod in the bearing. Its hard to explain, but I rolled it around on the disc splines and checked the distance to the pressure plate fingers. Then tighten the pressure plate down.

Like Zed Head I used the scissor jack under the back of the engine and the tranny on a trolley jack. Make usre you get the car high enough of the ground to give yourself enough room to move under the car.

Chas

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Another trick that I have used is to put the transmission in gear, and rotate the output shaft with my fingers while lining it up with the clutch. I use a transmission jack to hold the transmission up while getting it back in place, but still I admit to more than my share of cursing while installing the transmission the last time.

One time I had my adult son help and things went better, but the last time I did it by myself and it was a hassle.

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good advice. Just a note, since you mentioned the clutch alignment tool. I distinctly remember how hard it was to get that darn thing out once I tightened down the pressure plate. I actually popped out the ball and hoop that is inside the tool Once, I had to use a vice grip and hammer to tap it out. It was that tight. I have installed clutches in Camaros and Jeeps, and never had that issue. Maybe I am just being lazy. But if I drop the transmission again, I will definitely be getting the car 6" higher than last time. I struggled for a while getting that bell housing under the car, as the frame rail with the T/C rod was just not high enough. So I was not working smartly. I will definitely get a better transmission jack, as my harbor freight jack had exactly ONE good use until the gears stripped! HAHA. I will get this working no doubt. Just need to source a solid good 5 close ratio 5 speed first.

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I tried to install the flywheel and pressure plate evenly with symmetrical tightening /torquing of all bolts in steps to ensure correct alignment and fastening. I still had to slam the transmission harder than I wanted to make it mate (after ~ 20min of trying gentler methods).

I wonder if the problem is at the fly wheel area or up at the nose where the new bushing resides.

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