Jersey Posted December 5, 2012 Share Posted December 5, 2012 Sorry guys, I’ve done a bunch of research and have come up with some inconsistent information. I hope someone can clear it all up for me and also help others with any of these questions they may have. So, here goes… I’ve found a bunch of ’89 – ’96 SX 5sp boxes for sale - are they all the same no matter which year or model 240sx? Is the JDM trans for these years any different? Is the 240sx FS5W71C trans proven to be stronger than the 280zx FS5W71B’s? Synchros & pins seem to be the weak attributes on the ZX trans. Will the ZX clutch & PP work with the SX trans input shaft? Does the pilot bearing need to be changed in order to accept the SX input shaft? Is there any strength advantage to use the larger SX 62mm countershaft bearing rather than the ZX 56mm bearing? If using the SX 62mm bearing, I understand that the countershaft bearing hole in ZX bell needs to be increased from 56mm to 62mm. Is this measurement exactly 62mm? If using the SX 62mm bearing, does the raised boss around the inside of the ZX countershaft bearing hole need to be shaved down or is this just if using the ZX 56mm bearing or, does it need to be shaved no matter what? Is it exactly 16mm that the 1-2 shift rod hole in ZX bell needs to be enlarged too? Does the Z driveshaft mate with the SX tranny or do you need to use the SX front yoke? Is it exactly 2†that the driveshaft needs to be shortened? Does the early 240 driveshaft work without any modification needed? Sorry for all the questions. I'm just the type that likes to gather as much definitive information as possible before diving in. - Jersey Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 5, 2012 Share Posted December 5, 2012 Post the links that you've already looked at so people know where you're coming from. There are three that get referenced quite often. Quote Link to comment Share on other sites More sharing options...
Jersey Posted December 5, 2012 Author Share Posted December 5, 2012 I hate posting links to other Z sites but ok. Here's a couple that i can think of at the moment... http://zhome.com/ZCMnL/tech/240SX5spd/transmission.htm http://atlanticz.ca/zclub/techtips/240sxtransmissioninstall/index.html Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 5, 2012 Share Posted December 5, 2012 I asked because some of the people who put the effort in to sharing that information are members here. Like Nigel, who created this writeup - http://www.motortopia.com/cars/1973-datsun-240z-11118/car-pictures/240sx-transmission-swap-14041 - and Blue, who played a part in the atlanticz link. If you don't show your references you'll get answers from the same people who already gave you the information that you're wondering about. There are a few threads on this site that cover some of the questions, like the one about driveshaft length. I think that the 1-4 synchros (baulk rings) are the same part, from 1971 to well in to the 1990's 240SX transmissions. And the 240SX transmissions have 71H as the designator. Nissan used the 71_ transmssions in a lot of different cars and trucks and changed the last letter and some parts and dimensions along the way. Quote Link to comment Share on other sites More sharing options...
Jersey Posted December 5, 2012 Author Share Posted December 5, 2012 I understand and do appreciate your reply NewZed. I'm just looking for some hands-on concrete info. I'm sure a bunch of HybridZ'rs have done this swap and was hoping they'd share their findings. I've read many posts from many sites that have conflicting information and was just hoping to get it all sorted out. Thanks. Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 7, 2012 Share Posted December 7, 2012 Didn't mean to kill your thread. Here's one, re the 16 mm shift rod hole - I used a 16 mm drill bit and a drill press to very carefully enlarge the shift rod hole to 16 mm. It was too small and the shift rod bound up during test-fitting. So I used an aluminum rod, some scrothbrite and zip ties, and a hand drill to hone it out until it worked. I don't think it needs to be super accurate, the shift fork itself is pretty loose on the coupling sleeve. Quote Link to comment Share on other sites More sharing options...
voong413 Posted December 7, 2012 Share Posted December 7, 2012 (edited) I can also confirm the use of a 16mm bit to enlarge the shift rod hole. But regarding the driveline I have found different answers to the correct length. I had my driveline shortened 2in before realizing it may have been shortened too much. Over 1in of the input shaft was exposed when mounted. After more research I believe the variation in driveline may be due to the differnce of using the "cover-dust, sleeve yoke" and not using it. I'm currently still working on my swap and interested in knowing more measurements also. Another issue I encounter with the swap is finding the correct combination of throwout bearing collar, bearing, and flywheel. Edited December 7, 2012 by voong413 Quote Link to comment Share on other sites More sharing options...
Nigel Posted December 8, 2012 Share Posted December 8, 2012 Jersy, check out my very detailed write-up on this swap that NewZed already posted a link to. Covers just about all you would want to know, including some of the differences in the transmissions. The later S14 5 speeds are much stronger than the ZX boxes. I think the only thing I screwed up in my writeup was the driveshaft length. I have to remember to fix that. NewZed, Nissan switched to a dual cone syncro on second gear at some point for the SX box. To voong413, any Z clutch/flywheel will work with the SX box, so long as they're a matched set. For example, the Datsun 240mm 2+2/turbo flywheel, clutch and collar work with the SX swap. The SX collar is the same as the 2+2 collar. All the throwout bearings are the same. Nigel Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 8, 2012 Share Posted December 8, 2012 Good point on the daul cone, I forgot about that. Otherwise, though, I think that the single baulk ring synchros are exactly the same. On the clutch, don't forget that after the swap the trans has an L6 bellhousing. The only clutch part bolted to the trans is the slave cylinder and it's still bolted to the same L6 bell. So there's no need to change any of the clutch parts. Quote Link to comment Share on other sites More sharing options...
Xnke Posted December 8, 2012 Share Posted December 8, 2012 In 1984, the FS5W71C was born out of the earlier 71B box. It came with the 62mm countershaft bearing then. In 1986, the second gear syncro went to a double cone type. In 1987, the S12 200SX came with the 71G, which is a 71B box with the C shifter, upgraded 2nd gear synchro, nonsynchro reverse, and the large countershaft bearing...but the box is exactly the same length as a 71B box! No driveshaft mods needed. In 1989, the 71H received thicker gears, the large countershaft bearing, upgraded 2nd gear synchro, C shifter, nonsynchro reverse, and the case is two inches longer. A one-piece VSS sensor is used, as opposed to the two-piece sensor on the 300ZX. In 1995, the S14 got a further strengthened version, with some gears thicker still, big countershaft bearing, upgraded 2nd gear synchro, fully synchronized, including reverse, VSS sensor, different overdrive synchronizer (I have both a brass ring syncro and a black fiber crush sleeve type...not sure which is which, but both came from S14's) and the long case. This transmission also came in some of the 4wd trucks, and can be found with both married and divorced transfer cases. If you don't need a passenger seat, then it can be fitted up in a Z by removing a good bit of the passenger side transmission tunnel and reworking the floor...this allows you to enjoy the fun of fitting up a front diff and using the uprights from one of the Nissan FWD cars...I will leave the actual fitment up to the user to figure out. I don't remember the details and the car was never finished, or even driven at all. Quote Link to comment Share on other sites More sharing options...
jmhtx Posted March 3, 2016 Share Posted March 3, 2016 I've got a 1971 240z it currently still has the L24 in it. I am in the process of upgrading the drive train and engine as follows: L28 (some details to be determined) 240SX Transmission (modified 5 speed bell housing and transmission mounts) STI R180 New Moustache bar from a 1973+ New front diff mount from a 1973+ CV axles (and other suspension and brake items that I don't think are related). Before I get started, I want to make sure I've my ducks lined up, I've been through the various sites and posts most have related to the 73 and newer swaps. As I understand it, the 240SX transmission will bolt up with a modified bell housing and relocation of the transmission mount. I've read conflicting things about where the shifter will land in the 1971's but I think it lines up perfectly with the original position of the 4 speed shifter and will not hit the console. The 240sx is longer than the 240Z-280Z transmissions, but the 1970/71 has the rear diff more forward than the 73+ models. So I think if I relocate the rear diff to the 73+ and more rearward position with an new mustache bar and new front diff mount, I can use the 1971 drive shaft. Am I missing anything or have anything wrong? Quote Link to comment Share on other sites More sharing options...
NewZed Posted March 3, 2016 Share Posted March 3, 2016 Are you sure you have the forward-mounted diff? I get the impression that there was a retrofit available from the dealers if people reported vibration problems. Many were fixed. You can tell by looking at the angle of halfshaft with the wheel. If it angles forward, you have the original early position with the short propeller shaft. If it's perpendicular, it's the later version. Might save you some parts buying, or change what you're buying. Otherwise, it looks like a good plan. Make sure to match the diff and transmission ratios. Don't forget the speedo gear to match the diff ratio. Quote Link to comment Share on other sites More sharing options...
83turbo280zx Posted March 17, 2016 Share Posted March 17, 2016 I posted a write up on this almost a year ago for a 280zx, it's similar for the older chassis with the exception of the rear crossmember and the driveshaft lengths. I have a machine shop that is set up for boring the bell housings and drilling the shift rod hole, if you want to ship it to me to have it bored for you, or if you want to ship me the entire transmission and bell housing I can do it all for you. Here is my write up http://forums.hybridz.org/topic/122445-240sx-5-speed-swap-in-280zx/ The pictures don't pull up on the computer I'm on, let me know and I can re-up them.If it's for a 280zx, I have driveshaft specs as well and can have a driveshaft made for you as well. Quote Link to comment Share on other sites More sharing options...
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