FS5W71B Rebuild Thread - Tips tricks and discoveries!

[zKars]

WELL

I finally got a chance to take the “new” (to me) fancy hybrid extra yummy tranny out for a drive tonight. The roads are clear here, temp is +5C, beautiful night for a cruise. I have to get this thing out of the shop tomorrow anyway to get the next project car in there, and we have a good cold snow dump coming this weekend, so now or never. 

I am happy to report the trans works very well. MUCH quieter over all than the old rattle box (better be with new bearings and such). All gears change easy, new synchros are doing their thing just fine. Up and down all gears. That fancy 62mm front bearing in my gingerly machined out bore seems happy, but only time will tell about how well the counter shaft bearings stand up to the abuse I will be giving it over the next few years. Even the reverse light is happily coming on with my modified shift rod with the 4 speed bell housing.

Remember this is the one with mixture of a 720 truck ratio’s stirred with a 4 gear set from a close Ratio ZX 5 sp. The idea was that it gave a 0.65 ish 5th while retaining reasonable 1-4 The lower four gears are essentially identical to what i remember “feel” wise. 1st is maybe a tad taller, the 2-3 gap feels just a tad wider, but that 5th. OMG I love it.  2200 RPM at 100 KPH. The mighty 2.4 LZ has no trouble moving it right along. Going to make an excellent highway cruiser for this years planned trips.

Feeling good. Now there’s a chance all my other one’s that are now re-built will also move a car down the road with little drama.

 

 

[Dave WM]

That tall 5th is indeed nice, have fun!

[Patcon]

I followed this thread as it was going along, but I don't remember. Was the reverse gear ever analyzed for suitable replacements or interchange with other transmissions?

[zKars]

I’m sure none of the 4 speeds reverse gears are interchangeable with the 5 speeds (B) and having looked at the reverse/5th gear setup in the C type 5 speeds (with admiration about how you can make it so complicated), I’m going to say with some certainty that they do not have compatible components either. 

[Patcon]

1 hour ago, zKars said:

I’m sure none of the 4 speeds reverse gears are interchangeable with the 5 speeds (B) and having looked at the reverse/5th gear setup in the C type 5 speeds (with admiration about how you can make it so complicated), I’m going to say with some certainty that they do not have compatible components either. 

That's too bad. I am going to need a reverse gear for the 5 spd for Cody's goon. He wants to rework it next week but I doubt I can figure out what I need much less have all the parts in time

[Patcon]

Is there another source for the idler gear? Maybe a generic catalog? It's not a very complicated piece...

[Patcon]

Maybe somebody like this??

https://www.khkgears.us/

https://www.sdp-si.com/products/Gears/Index.php

https://www.ondrivesus.com/precision-gears/metric-series?gclid=EAIaIQobChMIl5Xpqd6_7QIVBaGGCh3ZiAXmEAAYASAAEgICdPD_BwE

I'm not sure I'm technically savy enough to find it though

[Patcon]

Thoughts about these two??

https://www.allstategear.com/FS5W71-Reverse-Idler-Gear-p/nis-10-22.htm?gclid=EAIaIQobChMIn5aAlfbI7QIVBHiGCh2twgTmEAQYASABEgLOhfD_BwE&Click=7567&utm_source=googlebase&utm_medium=shoppingengine

https://ampdistributing.com/products/1981-92-nissan-fs5w71-21-tooth-reverse-idler-gear?variant=5189686460445&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&utm_campaign=gs-2018-11-12&utm_source=google&utm_medium=smart_campaign&gclid=EAIaIQobChMIn5aAlfbI7QIVBHiGCh2twgTmEAQYAiABEgIhSvD_BwE

[zKars]

Both of those look like you hit the jackpot! 

36 minutes ago, Patcon said:

Thoughts about these two??

https://www.allstategear.com/FS5W71-Reverse-Idler-Gear-p/nis-10-22.htm?gclid=EAIaIQobChMIn5aAlfbI7QIVBHiGCh2twgTmEAQYASABEgLOhfD_BwE&Click=7567&utm_source=googlebase&utm_medium=shoppingengine

https://ampdistributing.com/products/1981-92-nissan-fs5w71-21-tooth-reverse-idler-gear?variant=5189686460445&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&utm_campaign=gs-2018-11-12&utm_source=google&utm_medium=smart_campaign&gclid=EAIaIQobChMIn5aAlfbI7QIVBHiGCh2twgTmEAQYAiABEgIhSvD_BwE

 

[Patcon]

15 minutes ago, zKars said:

Both of those look like you hit the jackpot! 

 

Except the gear in the tranny is 23 teeth and one of those is 22t and one is 21t!

[zKars]

41 minutes ago, Patcon said:

Except the gear in the tranny is 23 teeth and one of those is 22t and one is 21t!

Then that's a bad thing. It is the correct design..... Sorry

Let me see if I have a 23 tooth reverse idler...

[dutchzcarguy]

I see there is stated a 280zx has a C type box? where i know it's a B.. A 280zx has never had a Fs5W71C always a B   i could be wrong ofcourse.  So they (also) don't know it all..