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620 Transmission swap?


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The output splines are the same for auto/std on the 620. The rear seals are the same for '63 to '90 trannys.

 

An '80 4X4 5 spd won't work for you on a 2 wd truck. A 2wd is fine.

 

thank you very much!! this saves me some grief of pullin the driveline to see if they were the same.

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thank you very much!! this saves me some grief of pullin the driveline to see if they were the same.

 

The length is the biggest deciding factor. Long trannys are about 31 1/2" auto or standard, shorts are about 26". If your 4 spd is long, a long 5 will fit without drive shaft mods. Just take a tape measure with you when tranny hunting.

 

If I remove a tranny I take Everything. Clutch/flywheel/throw-out bearing/slave complete/maybe the drive shaft. If they ask I say the tranny wont convert over without the other stuff. They always shrug and take the money. Datsun guys are cheap and wrecker owners are such whores. Match made in heaven.

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well when i was under the truck when i was lowering it, i measured the auto and it is 31 inches give or take a few 1/4s of and inch. the 5 speed from the 2wd 720 is also 31. the tranny mount is also in the same place on the 5 speed as the auto. so as long as the yoke is the same, it should just bolt in.

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Good! Absolutely.

 

The ratios for the '80 720 FS5W71B w/L20B should be:

1st....2nd....3rd...4th..5th

3.592 2.246 1.415 1 0.813

 

The really low 1st 3.592 coupled with your 4.375 rear end should give great take offs. Expect lots of snap compared to the 3N71B.

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An 80 4x4 5 speed will work in a 2wd truck.Why would it not.It has a divorced transfer case.Same tranny as a 620.We yanked one last year and it is in my friends 620 as we speak.

 

Simple. The Transfer case has the speedo cog in it. :D I have an '80 4X4 trans and the tail stock does not have the cog hole drilled out on it, so you would not have a speedo. But the tranny would work.

 

Datsunahaulic has seen them with block off plates, so a cog could be installed on it, but the L one I have does not, nor have I seen a Z 4X4 5spd with one. And I've seen at least 7-8.

 

An L 5 spd tail stock (with cog) could also be swapped onto it, I guess. But you would have to find one too.

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well when i was under the truck when i was lowering it, i measured the auto and it is 31 inches give or take a few 1/4s of and inch. the 5 speed from the 2wd 720 is also 31. the tranny mount is also in the same place on the 5 speed as the auto. so as long as the yoke is the same, it should just bolt in.

 

 

im jelous i want that tranny i have to fab to make a short tail fit in a longtail car :(

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Good! Absolutely.

 

The ratios for the '80 720 FS5W71B w/L20B should be:

1st....2nd....3rd...4th..5th

3.592 2.246 1.415 1 0.813

 

The really low 1st 3.592 coupled with your 4.375 rear end should give great take offs. Expect lots of snap compared to the 3N71B.

 

cool deal!! thanks for the ratios. i was wonderin what they were.

 

the auto is nice but its a big change from drivin a chevy luv with a worked over 2.0l and 4 speed. the l20b is pretty potent with the auto when i manually shift it, so it should be a fun little driver with the 5 speed.

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  • 6 years later...

To what model and years you guys talk about the short tail and long tail? You guys talking about the actual body from the truck the 4hooks side bed (short tail) or the 5hooks side bed (long tail) or you guys talking the actual length of th tranny from head to toe measurement ?

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The '80-'86.5 720 had long 31.5" and shorty 26" length 5 speeds.

 

LONG (L series 5 speed but basically the same as the 720)

79KC5spd.jpg

 

SHORT (from a 4x4 720)

83FS5W71Bshorttail001Large.jpg

 

 

Here is a Z series shorty with a front case from an L series swapped on. This will fit any L series car (with a mount mod) with a 26" long 4 speed such as the PL 510, PL521, 710, A10 without having to change the driveshaft length.

trannyFS5W71Bshort0ne.jpg

 

I never figures out what years or models got them. Ask Doug... http://community.ratsun.net/user/2344-sealik/

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