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cruznude

Just need some questions answered

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Ok, there’s this man not to far from me selling a 1980 720 truck for 400.00 and he says there’s water in engine. Probably cracked head. Anyways my interest isn’t there. It’s a 5 speed tranny and rear end im after. Along with little parts here and there. Is this still an l20b?whats the differences with rear end ratios and will tranny bolt right in? What can I expect to use off this truck? Remembering my truck has no smog devices at all. Definitely probably fit up back leafs. Lower control arms and such.

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'80 will be an L series engine. Look on top edge of block behind the dipstick handle says L20B.

 

Heads generally don't crack but more likely a blown head gasket. If overheated it may be warped but a light surface trim and it's good again. So I would assume you would have a head included .

 

The 5 speed will bolt right onto your '79 and has the same ratios..

 

 

Depends on the truck but 3.889, 4.11 were available on the 5 speed. Look on the engine tag under the pass side hood hinge on the inner fender. Bottom left says TRANS/AXLE....... FS5W71B... HL38 or HL41

 

Drive train, engine, brakes, spindles, wheels should swap. 

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But if late 80 production, could be z20?? Thought late 80's were 81 model yr. Trans well work with bellhousing(front half of trans)swap. Z20 in same basicly same block. So l head would fit it.

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The 720 Mileage Option Z20(S) engine came out at the same as time the Z24 engine with build dates of Oct. '83. The change over to the next model year is usually June of the previous year.  So it would appear that from 'June '82 till about Sept there were Z22 powered '83s.

 

The '80 720 was almost a '79 620 but with a 720 body on it. It was unique in being the last year an L4 L20B was used. The wiring and electrical was different from later 720s and the 4x4 front differential was on the opposite side to all later 4x4s.

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80 720 is EI dizzy.

 

Use it, or sell to get back a quarter of your cost.

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The engine may even be quite good. Change the head gasket (about $25) and see how well it drives, test out the 5 speed while you're at it before swapping it to find out.. Yeah that a steal for spare parts

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Ok, there’s this man not to far from me selling a 1980 720 truck for 400.00 and he says there’s water in engine. Probably cracked head. Anyways my interest isn’t there. It’s a 5 speed tranny and rear end im after. Along with little parts here and there. Is this still an l20b?whats the differences with rear end ratios and will tranny bolt right in? What can I expect to use off this truck? Remembering my truck has no smog devices at all. Definitely probably fit up back leafs. Lower control arms and such.

 

It really depends on if it has an L20b and if it is a 2wd truck, I have seen several 1980 Datsun 720 trucks that had a Z22 in them, also the 1980 Datsun 4wd truck with an L20b has 4.6 gears in the rear axle, so if it is not an L20b 2wd truck there isn't a lot your going to be able to use.

Also the tag on the inner fender of a true 1980 Datsun truck doesn't have the rear axle info, only the 1981 on(Z22 engine) had this info on that tag, the 1980 Datsun 720 is a unique truck, it's a one year truck with a lot of one year parts, the brakes should be the same as your 76 Datsun 620.

You really need to get a good photo of the engine compartment from him if you can to know if it is worth the drive unless it is close, then just drive over and look at it.

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Yea he told me not Napa motor and 2 wheel drive. Hell with it, I’m going to get tomorrow after work. Offer him 300.00 and off the property,,,back to being busy.thanks guys post pics when I’m gets here. Oh I’ll be in Tucson for10 days plumbing another Denny’s restaurant. Driving my 620 also. Let’s get together!,,,,

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It really depends on if it has an L20b and if it is a 2wd truck, I have seen several 1980 Datsun 720 trucks that had a Z22 in them, also the 1980 Datsun 4wd truck with an L20b has 4.6 gears in the rear axle, so if it is not an L20b 2wd truck there isn't a lot your going to be able to use.

Also the tag on the inner fender of a true 1980 Datsun truck doesn't have the rear axle info, only the 1981 on(Z22 engine) had this info on that tag, the 1980 Datsun 720 is a unique truck, it's a one year truck with a lot of one year parts, the brakes should be the same as your 76 Datsun 620.

You really need to get a good photo of the engine compartment from him if you can to know if it is worth the drive unless it is close, then just drive over and look at it.

 

If the first or second letter on the engine tag is an H this is the descriptor for the L20B engine. M would be a Z22 engine but these were an '81 model year engine with a build dates starting June of '80. Just because it says '80 on the build date does not make it an '80 720.

 

The '80 720 4X4 Long Bed was the only one with the 4.625 differential. All other King and Regular cabs were 4.375

 

The '80 would have the same brakes as the '78 and '79 with front disc. Pretty sure this is what you meant.

 

The driver's door jam should have a tag with the build date on it.

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Beware: my 1980 5 speed didn't have a speedo cable drive on it.  You may have to go to an aftermarket GPS speedo if you're taking it from a 4x4 and installing into a 2WD.  

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Beware: my 1980 5 speed didn't have a speedo cable drive on it.  You may have to go to an aftermarket GPS speedo if you're taking it from a 4x4 and installing into a 2WD.  

 

That would be from a 4x4 720. Speedo was in the transfercase. 

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