@@@What 5spd tranny will fit my 71' 521 truck?@@@

[rhabdo71]

I'm just getting to know these Datsun 521's. My truck is in the shop and I was told that the shifter assembly connecting to the transmission needs replacement. The shifter does have alot of play but the gears go in very smooth and tranny pulls strong. Would be nice to have that extra 5th gear for the highway.

 

Does anyone know if I can pretty much bolt on a 5spd tranny to my exisiting L16 engine from a 240z or another car without any modifications? The shop where I have my truck wants to charge $700 to fix my tranny. I think I'd rather swap out the tranny and put a 5spd in it. Would be a nice little upgrade. Can anyone help, thanks.

[Laecaon]

You have a couple of options.

 

Dogleg: You will need to make a new tranny mount. Driveshaft needs modding...Has come up a few times recently.

 

620 5speed: Not sure about mount, use front half of 620 driveshaft, or so I hear.

 

Diy 5speed (probably easiest to find reliably): http://community.ratsun.net/topic/28473-how-to-put-together-a-shortshaft-5-speed-for-a-l20b/

[rhabdo71]

Thanks for the response. I'm looking for a quick bolt on swap. Need the truck on the road as soon as possible. Thanks, does anyone else have a say?

[datzenmike]

If you do a lot of highway driving and don't use it to carry loads it would be easier to change the rear end. A 3.889 or 3.70 from a later 720 2wd would lower the RPMs on the highway. Cheap and easy to do.

 

Your 521 has a 26" long transmission very very similar to the 510, 710 and the early 620. Luckily, the 5 speed from a '77-'79 S10-(200sx) is the same length and will fit without having to shorten the driveshaft. This 5 speed is called a dogleg because of it's distinctive shift pattern with reverse above first.

 

If you take a look at your driveshaft where it enters the transmission you'll see that it actually bolts on. The output spline has a flange on it that bolts to a flange on the driveshaft. Once the driveshaft is disconnected you'll see that the spline can be unbolted from the transmission and will slide out. The dogleg has a normal driveshaft that simply slips into the end of the transmission and the one from the 521 can be used.

 

521 4 speed with the bolt on output flange. The large nut on the end holds the spline to the output shaft.

 

 

521 4 speed with the spline removed and nut put back on.

 

 

Because the 521 spline is held on with a nut there is a hole in the end of the flange that will drip transmission oil. This can be plugged with a 40mm frost plug.

 

Dogleg 5 speed with plugged 521 spline installed..

 

 

The 521 transmission mount will need to be shortened so it moves back. I would install the transmission and measure, then cut.

 

 

 

Shortened 521 mount

 

You may have to cut a notch in the floor for shifter clearance.

 

.

[banzai510(hainz)]

I was told that the shifter assembly connecting to the transmission needs replacement. The shifter does have alot of play????

most do whats wrong with it???????????

 

Most get a big and sqeeze the tangs or Ears so it makes it tighter or add washer inbetween the slop.

 

If still works just run it.

 

521s are hard to get at trans stuff. To me it isnt EZ as a 510.

[banzai510(hainz)]

521 trans are free to about 50$

[Jayden71]

I am doing the dogleg swap in my 521 next weekend. I am using a 1 piece driveline from a 720 to replace current one. From prelimanary measurements it will fit with no mods! :thumbup:

[xxmass]

can you please share knowledge about the clutch and it's part of the equation. some parts from the 200, some from the truck?

[datzenmike]

Both the 521's L16 and the 200sx L20b car used the same diameter clutch so the 200sx 5 speed should bolt on and work as is. However there are some very small differences with the housing (or collar or sleeve) that holds the release bearing. Since the collar length is intimately matched to the exact clutch used I would keep and use the one on the 521. This way clutch / pressure plate and release housing remain as a matched set even though the transmission changes.

 

Use the 200sx 5 speed slave cylinder and clutch arm on it and use with the 521 PP and clutch disc and release bearing housing. Always replace the release bearing.

 

Compare the housing lengths (but don't mix them up) and see if they are slightly different. Just curious.

[xxmass]

thank you.

[rhabdo71]

Thanks EVERYONE for the input! The tranny is strong and smooth just have more play on the shifter between gears than normal.

 

For example, when I have it in 4th gear the shifter can be moved from side to side about 4 inches. I don't have the time to weld or send parts to be welded or any other modifications. I think I'll just use the tranny i have in it and look for another 4speed when the current one goes out. Thanks again!

[datzenmike]

32855-H1010 Is the Nissan number for the two small plastic bushings on the shifter pin. ($4)

32861-N4200 Is the Nissan number for the small cup bushing that goes on the bottom end of the shifter. ($4)

 

Get these replaced and you will see a huge difference in shift quality.