Info -- 521

[silentcry1]

I had a question. I found a good 1973 Datsun truck in the junk yard. I have a 1970 Datsun 521 truck. I wanted to know if the suspensions are the same and if it will fit my truck. Also does any other parts from the 1973 truck fit my truck.

[flatcat19]

Hit or miss. Being an early 620, some stuff MIGHT, some stuff doesn't. 

 

What are you looking to get that you need?

[thisismatt]

So you want to swap your crappy kingpins and drum brakes for some crappy kingpins and drum brakes?

 

 

[flatcat19]

So you want to swap your crappy kingpins and drum brakes for some crappy kingpins and drum brakes?

 

 

 

 

Hory sheet. I'm rolling over here. Kudos. 

[MicroMachinery]

That's rich.

[DanielC]

I have found that the parts used on early 620 trucks in some cases are the same size, but the fasteners, (nuts and bolts) on 521 trucks are imperial, specifically a SAE standard, and 620 trucks are metric.  

A rear wheel cylinder off a 521 fits a 620, I think, and a rear wheel cylinder off a 620 will fit a 521.  However, the rear wheel cylinder in a 521 is held to the backing plate with 5/16-24 studs, and nuts, and the rear wheel cylinder on a 620 is held with M8-1.25 studs and nuts.  The flare nut for the brake line is 3/8-24 on a 521, and M10-1.0 on the 620.

I may be off on the exact metric thread size, I have 521 trucks, and I have not had a 620 right beside it to try to swap parts back and forth between the two different models.

 

Some metric sizes convert to inches easily.  3/4 is within a few thousands of an inch to 19 mm.  5/16 is close to 8 mm.  

 

I believe brake drums will interchange from 320, 520, 521, 620, and even some 720 rear drums.  I could be wrong on that. 

[thisismatt]

Daaaaamn Daniel, back at it again with the helpful info!

[4perrev]

Dude, that is too funny up there with the crappy to the crappy and picture. Sweet. Seriously, if you have a 521, you should just do the disc brake conversion!