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pogden

FS5W71B transmission identification (close-ratio vs. wide ratio) - with pictures

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Watch out with gearboxes, there are many versions that look the same but are not!

9 hours ago, pogden said:

The wide ratio gearbox has two exhaust hanger ears on the rear extension housing, the close ratio has only one (on the driver's side).

 

This is not true for the euro version FS5C71B gearbox that came in europe in the 240z 1971 to 1973.   I got one here and it has 2! ears..

 

9 hours ago, pogden said:

The wide ratio has a dust collar/shroud surrounding the end of the tail piece, the close ratio does not.

Oh yes! my close ratiobox has one!

 

9 hours ago, pogden said:

On the close ratio, the screw that secures the speedometer drive assembly to the rear extension housing is located at 6 o'clock (toward the bottom of the transmission), on the wide ratio the screw is at 12 o'clock (toward the top).

Wrong again .. 😂   On my close ratio box it's... at 12 o'clock! 

So one could think it's a wide one but no this box came out of an original dutch 240z and i'm shure it's a FS5C71B  not a FS5W71B (got those to btw.. reserve for my 280zx)

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This is nice work.  In the States what you're showing will be true 99.9% of the time.  The things dutchz are talking about might be true over there, but I can't think of a case over here where somebody has described what he's talking about unless you get in to the odd truck transmissions.  The truck transmissions use a different tail shaft housing.  For the Z cars though, that's a great guide.

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Excellent Pictures!  Best I've ever seen. Thank you.

Let's not forget the 1980 variant that shares the same external appearance with the close ratio box, but has short shifter ears. The ratios are listed below.

   81-83CR        1980     1977-79
3.062 3.062 3.321
1.858 1.858 2.077
1.308 1.308 1.308
1.000 1.000 1.000
0.745 0.773 0.864

The transmissions in discussion here the ones found in North American 77-78 280Z's then 79-83 ZX's.  As Dutchzcarguy guy said, there are other 5 speeds that don't fit these descriptions. 

It is simply what most north american's are going to run across when you they find a 5 speed. Use with care. 

 

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@dutchzcarguy, thanks for adding the detail. I knew that Euro-market 240Z's were available with 5-speeds, but the specifics you added here are great. And I'll edit my original post to make it clear that I'm in the US, and my comments are based on what I've seen/heard about Z's here.

@zKars, the wide ratio gearbox in my photos came out of a 280ZX - I believe it was a 1979 - I removed i myself (with help from my local Z buddy @Randalla). I'm honestly not certain of the origin of the close ratio box - I bought in on eBay - but it was said to be out of a 1983 280ZX. 

It is my understanding that the term "close ratio" refers to the difference between 2nd and 3rd. Looking at your table, either of the two later model 5-speeds would be considered "close ratio", right? 

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I think that "close" actually refers to the spread between first gear and top gear.  First on the wide is 3.321, on the close it's 3.062.  Top gears are similar, and 4th is always 1.0.

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Very nice photo's. Looks nice

I made a document in 2014 to help explain the differences between thre three versions used in the North American 280Z and 280ZX.

BTW My photos are crap conpared to yours.

 

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Very nice photo's. Looks nice
I made a document in 2014 to help explain the differences between thre three versions used in the North American 280Z and 280ZX.
BTW My photos are crap conpared to yours.
 


Cell phone cameras have improved quite a bit in half a decade, eh? :-)


Sent from my iPad using Tapatalk Pro

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19 hours ago, pogden said:

I knew that Euro-market 240Z's were available with 5-speeds

To ad, The euro version also has a different diff..    I converted my 240z from 4 speed (US type)  to  5 speed (Euro type) and had to change the differential also because with a euro 5 speed and a US. differential you get a very large first gear that will eat your clutchdisk every time you pull away..  As my car has a km speedo it ran till over 50-60 in first gear.. don't remember how high it was only that it was way to high.

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I'm trying to ID my transmission because I need to check if parts are still available. All I know is that it came out of a 280z or zx since it was installed in my 260 around '83. Based on the retaining bolt placement above the speedo cable and the two tabs on the tail end of the transmission housing it is likely a wide ratio FS5W71B. Is this the only potential transmission or do I need to dig deeper. There is an L3 on the housing if that helps.

Also, from talking to a transmission specialist, my problem of popping out of gear may be related to worn shoes or forks. If he is on the right track, are these components still available? I'm going to pull my center console out to see if something is blocking the shifter before bringing it in just in case it's a simple issue.

Thanks in advance...

Jeff

PXL_20201104_181403730.jpg

PXL_20201104_181349710.jpg

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Your ID looks right.  It also has the dust/dirt shield over the slip yoke area.  Which gear does it pop out of?  There's quite a bit about shift lever interference causing 5th gear to pop out or not engage completely.

Blown up bearings are common also.

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3rd gear is the issue. 

Are parts generally still available? Zcar Depot sells a rebuilding kit that includes seals, bearings, and synchros. But if it's something else, is it possible to still get parts?

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EuroDat put a paper together and has posted a lot about rebuilding.  The parts are generally available.  I think that you can get them cheaper than at ZCD if you search around.  Seems like there are one or two sets of parts that everybody resells.  There might be extra parts in a kit or a couple of missing parts, but the bearings and seals in the kits seem to be of good quality.  The synchros can be questionable.  Have you found any metal on the drain plug magnet?

 

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2 hours ago, Jeff Berk said:

I'm trying to ID my transmission because I need to check if parts are still available. All I know is that it came out of a 280z or zx since it was installed in my 260 around '83. Based on the retaining bolt placement above the speedo cable and the two tabs on the tail end of the transmission housing it is likely a wide ratio FS5W71B. Is this the only potential transmission or do I need to dig deeper. There is an L3 on the housing if that helps.

Also, from talking to a transmission specialist, my problem of popping out of gear may be related to worn shoes or forks. If he is on the right track, are these components still available? I'm going to pull my center console out to see if something is blocking the shifter before bringing it in just in case it's a simple issue.

Thanks in advance...

Jeff

Hi Jeff,

It looks very much like a wide ratio FS5W71B out of a 280Z or a 280ZX 2+2. The L3 is a casting mark from the manufacturer and doesn't mean anything regarding type of transmission, ie wide or close ratio.

Popping out of third is caused by an accumilation of wear in several bearings in the transmission, but also springs in the selectors. This typically happens in third because the wear in the needle bearing between the input and main shaft, and third is the furtherest away from the adapter plate bearing. The selector springs loose tension over time and the extra stress caused by the worn bearings pushes it out of gear.

The spring is in the selector parts list in the link @Zed Head posted. 32831N is the part number. They can be replaced with the transmission in the car.

The springs cost a couple of dollars and with a good oil you should be able to drive trouble free for some time. GM or AC Delco make a very good oil for these transmissions. I would try this before doing an expansive rebuild.

 

 

 

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My wide ratio gearbox (the one in the pictures at the top of this thread) pops out of 2nd gear. Not always when upshifting, but always when downshifting. I've been reading everything I can on this site about overhauling one of these things, and I am going to give it a shot. I just received the rebuild kit from Rock Auto, which seems to be the exact same one sold by other places as described in @zKars's lengthy  FS5W71B Rebuild Thread, and it was <$60. I also ordered a bunch of other small parts (seals, main shaft and countershaft nuts, detent springs/balls, oil gutter, Torx screws) that I might need from Courtesy Nissan. I did not order any of the big parts (gear sets, shafts) - I understand that many of those are NLA. 

Regrading slipping out of gear, I have no idea why it's doing that, but I hope to find out. My *guess* is either a problem with the 1-2 baulk ring or maybe one of the detent springs. Thanksgiving project, I hope. 

 

 

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30 minutes ago, pogden said:

My wide ratio gearbox (the one in the pictures at the top of this thread) pops out of 2nd gear. Not always when upshifting, but always when downshifting. I've been reading everything I can on this site about overhauling one of these things, and I am going to give it a shot. I just received the rebuild kit from Rock Auto, which seems to be the exact same one sold by other places as described in @zKars's lengthy  FS5W71B Rebuild Thread, and it was <$60. I also ordered a bunch of other small parts (seals, main shaft and countershaft nuts, detent springs/balls, oil gutter, Torx screws) that I might need from Courtesy Nissan. I did not order any of the big parts (gear sets, shafts) - I understand that many of those are NLA. 

Regrading slipping out of gear, I have no idea why it's doing that, but I hope to find out. My *guess* is either a problem with the 1-2 baulk ring or maybe one of the detent springs. Thanksgiving project, I hope. 

 

 

Might experience. Worn bearings and weak detent springs 32831N. Change the bearings or springs or both and you should solve the problem.

If it goes into 2nd gear without grinding, then there is nothing wrong with the balk ring or the springs 32602N in the hub. If those springs weaking they do not apply enough pressure to the baulk ring and release the hub too soon, before the gears can synchronise and then you grind gears.

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5 minutes ago, EuroDat said:

Might experience. Worn bearings and weak detent springs 32831N. Change the bearings or springs or both and you should solve the problem.

If it goes into 2nd gear without grinding, then there is nothing wrong with the balk ring or the springs 32602N in the hub. If those springs weaking they do not apply enough pressure to the baulk ring and release the hub too soon, before the gears can synchronise and then you grind gears.

Thanks, Chas. I just might be able to fix this then - I also ordered the large roller bearings (the ones not included in the rebuild kit, for some reason). What you say about the baulk rings makes sense, but I'll probably replace them anyway (cuz I have 'em). But I'll give the old ones a good inspection first. 

 

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EuroDat and Zed Head... Thanks for the help. I downloaded the service manual for the FS5W71C from NICOclub and it shows the first thing to check for wear are the plug return spring and ball. The diagram provided by Zed Head shows 3 of them. 

EuroDat, how do you access them without removing the transmission? Are the plugs visible on the outside of the transmission? If so, can you point them out on one of the photographs in the first post of this thread?

I'm going to pull the drain plug this weekend and check for metal shavings. There weren't any 3 years ago when I pulled and reinstalled the transmission, but that was 3 years ago.

Jeff

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Here is a photo where you can just see the two side detents in the red circle ( 3rd/4th and 5th/reverse) the other one (1st/2nd) goes in from the top and is the hardest to replace. It helps to lower the rear transmission mount and crossmember to give yourself more room.  You will also need a small pencil style magnet to remove the spring and ball.

 

 

Check_and_Interlock_Balls.jpg

Screenshot_20201106-091847.jpg

Edited by EuroDat
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Thank you... I think I found them using your annotated photos. Switching out these inexpensive items are worth a shot before having the transmission rebuilt. 

Do I need to spray anything in the holes after removing the springs and check balls to clean out gunk or should they be fine.

Euro Dat, That is one clean transmission!

Jeff

Transmission Detent Access.jpg

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54 minutes ago, Jeff Berk said:

Thank you... I think I found them using your annotated photos. Switching out these inexpensive items are worth a shot before having the transmission rebuilt. 

Do I need to spray anything in the holes after removing the springs and check balls to clean out gunk or should they be fine.

Euro Dat, That is one clean transmission!

Jeff

Thankyou. You shouldn't need to clean out the holes. Not much debris gets in there unless a ball has completly fallen apart.

When you remove the springs, compare the free length with the new one. You should also notice theold springs compress easier when you depress them.

Your problem is an accumulation of things. Removing the (weak springs) issue will give you some time. Maybe 10 to 20 thousand miles before it really needs rebuilding.

Don't forget to change the oil for a good quality gear oil like Red-Line MT-90 75W90 GL-4 Gear oil. There is also the GM and AC delco friction modified syncromesh transmission fluid. AC DELCO USA part number is: 88900399. GM USA part number is: 12377916.

Last thing. When you drop the cross member don't drop it too far and check the top radiator hose and fan that they don't get damaged.

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FYI, the drain plug didn't look too bad so hopefully the new springs will take care of things. I'm picking up the Red-Line tomorrow.

Thanks all.

 

Transmission drain plug.jpg

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Looking at the rag, the oil looks like it needs changing. The sludge on your drain plug is normal. No chunky pieces.

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