720 2 wheel drive transmission length

[Icehouse]

Why does it seem to measure the same length as the stock 510 4 speed?  Why haven't I heard of this before?  Datsun Mike?  

[Lockleaf]

It depends on the trans. The 720 came with both long and short series in both the 2wd and 4wd. So pay attention to which one you're looking at.

 

Short is 26". Long is 31.5".

[wayno]

The 1985 and 1986 Nissan 720 regular cab/short box 2wd came with a shortshaft 5 speed, it came with a Z24 type front case(engine tilted to the right), it is the same length as the stock Datsun 521 4 speed and the dogleg 5 speed in the 200SX.

Now if you want to use this transmission in your L block 521 all you need to do is get the front case off a 1980 Datsun 720 4 or 5 speed and bolt it onto the late shortshaft 5 speed transmission, all that will need to be done is to make a shorter transmission mount that will lower the tail of the transmission a couple inches so it doesn't hit the tunnel, and modify the 521 yoke, or put another yoke on the driveline from a later 620/720, I also believe that one can use a 520 one piece driveline.

If you already have a dogleg 5 speed in your 521 truck, this transmission will bolt right in in it's place without any more mods.

It will also fit a 510 I believe, but I don't know about the transmission mount mods in that application.

I wrote a how to article in the how to section, it's a bit crude as I am not a writer, but most get the idea, there is also a chance that the late 620 5 speed case will also work.

One cannot use the 4X4 short shaft 5 speed because it doesn't have a speedo drive, as they use the transfer case for that, but one should always check all the 4X4 trucks in the wrecking yards in case they replaced that broken transmission with a 2wd transmission with a speedo drive.

The best thing about this transmission is that the shifter comes out the stock shifter hole, and it is a much stronger transmission than the dogleg 5 speed, although it likely would not make a difference in a 510, as that is a light car like the 200SX and you can only haul so much in a 510.

http://community.ratsun.net/topic/28473-how-to-put-together-a-shortshaft-5-speed-for-a-l20b/

[Charlie69]

Great info Wayno thank you for sharing!

[datzenmike]

Great info Wayno thank you for sharing!

Agree, can't add much to that.

[Phixius]

I got some info for the 'C' type trans and comparison to longtail 5spd...

 

Tranny measurements. ..

Bell to dust shield..
S14 KA -- 33 1/2"
Longtail (L) 5spd -- 31 1/4"
Track KA/Z24 30 1/2"

Bell to output shafts
S14 KA -- 33 5/16"
Longtail 5spd (L) -- 31 1/2"
Truck KA/Z24 -- 29 15/16"

Shifter hole location
S14 KA -- 31 1/2"
Longtail 5spd (L) -- 29"
Truck KA/Z24 -- 26"

 

pictures.

 

[Icehouse]

So won't a 280zx bell housing swap on?  To make it L series compatible?  

[wayno]

As far as I know, an L block is an L block so if it is an L28 then it should work, although I have never myself tried to use a early 620 5 speed case(pre 1980), But I do have a diesel case on an early(pre 1980) transmission.

I did fail to mention that the 1985/1986 Nissan 720 shortshaft transmission has a larger lower cluster gear bearing, so the big bearing has to be removed with a puller and the smaller bearing installed to use the earlier L case.

I did have a couple Diesel cases/front bearing cover machined out to the larger clustergear bearing size when that hole got buggered up from a bearing going bad, but I had to find a machine shop capable of doing that in such a deep case.

[uberkevin]

As wayno said you could maybe use a 620 front case. This is what I did when making the short tail 5 speed for my 521.

 

I don't see what you wouldn't be able to us the zx case... as log as its l.

[datzenmike]

I got some info for the 'C' type trans and comparison to longtail 5spd...

 

Tranny measurements. ..

 

Bell to dust shield..

S14 KA -- 33 1/2"

Longtail (L) 5spd -- 31 1/4"

Track KA/Z24 30 1/2"

 

Bell to output shafts

S14 KA -- 33 5/16"

Longtail 5spd (L) -- 31 1/2"

Truck KA/Z24 -- 29 15/16"

 

Shifter hole location

S14 KA -- 31 1/2"

Longtail 5spd (L) -- 29"

Truck KA/Z24 -- 26"

 

pictures.

 

 

 

What method did you use for measuring these?? How exactly.

[HOGIE]

The 1985 and 1986 Nissan 720 regular cab/short box 2wd came with a shortshaft 5 speed, it came with a Z24 type front case(engine tilted to the right), it is the same length as the stock Datsun 521 4 speed and the dogleg 5 speed in the 200SX.

Now if you want to use this transmission in your L block 521 all you need to do is get the front case off a 1980 Datsun 720 4 or 5 speed and bolt it onto the late shortshaft 5 speed transmission, all that will need to be done is to make a shorter transmission mount that will lower the tail of the transmission a couple inches so it doesn't hit the tunnel, and modify the 521 yoke, or put another yoke on the driveline from a later 620/720, I also believe that one can use a 520 one piece driveline.

If you already have a dogleg 5 speed in your 521 truck, this transmission will bolt right in in it's place without any more mods.

It will also fit a 510 I believe, but I don't know about the transmission mount mods in that application.

I wrote a how to article in the how to section, it's a bit crude as I am not a writer, but most get the idea, there is also a chance that the late 620 5 speed case will also work.

One cannot use the 4X4 short shaft 5 speed because it doesn't have a speedo drive, as they use the transfer case for that, but one should always check all the 4X4 trucks in the wrecking yards in case they replaced that broken transmission with a 2wd transmission with a speedo drive.

The best thing about this transmission is that the shifter comes out the stock shifter hole, and it is a much stronger transmission than the dogleg 5 speed, although it likely would not make a difference in a 510, as that is a light car like the 200SX and you can only haul so much in a 510.

http://community.ratsun.net/topic/28473-how-to-put-together-a-shortshaft-5-speed-for-a-l20b/

I'm digging up this thread because it has some good information.

 

My question. Wayno, you said when looking in junk yards to look at 4x4's for the 2wd trannys, so it's possible to run the 2wd in a 86 4x4?

 

Also 86 was a special cross over year and the 86 d21 had the KA trans, did the 720 also have the KA trans or did they still run napZ trans?

 

Thanks

[datzenmike]

You can run a 2wd trans in a 4x4 but not the other way round. Well you can but the 4x4 trans does not have a speedometer sleeve and pinion so no speedometer on a 2wd.

 

The half year '86 720 was the end of the 71B and switch to the 71C in the Hardbody even though the engines were still Z series. By '88 the KA series was introduced. Z and KA series have the same engine bolt pattern but transmissions before 86.5 and after 86,5 are different lengths so they won't just swap easily.

[wayno]

I'm digging up this thread because it has some good information.

 

My question. Wayno, you said when looking in junk yards to look at 4x4's for the 2wd trannys, so it's possible to run the 2wd in a 86 4x4?

 

Also 86 was a special cross over year and the 86 d21 had the KA trans, did the 720 also have the KA trans or did they still run napZ trans?

 

Thanks

Yes you can use a 2wd 1985/86 short shaft transmission in the 4X4, it's the same transmission except for the tail housing has the speedo drive, it will bolt right in like it was a 4wd transmission, that is why I said to check all late 4wd 720 trucks for a 2wd transmission.

[HOGIE]

Thanks Wayno.