78 datsun 620

[tmac1991]

I have a 78 datsun with a 5.0 and a t5 trans.everything was put in really good and clean, But whoever put it in did not change the  rear end.  I wanted to know how  strong the rear end is. I have a mustang 5.0 rear end but it is 5 lug. And the truck is 6 lug. How can I change front?

[Eagle_Adam]

ok......

 

 

lets start with pics of your truck

[Eagle_Adam]

maybe a hi my name is..... 

[]2eDeYe]

I agree with Adam :)
 

 

620 rear ends have large shafts and decent sized ring gear, they are rated as 3/4 ton trucks. That said I have broken one rear end out of the 5 or so trucks I have owned. It was the center pin that broke and it was due to my abusive driving style.

 

[Stoffregen Motorsports]

You might be able to re-drill the stock front hubs, but I would take a different approach and swap in a 6 lug rear axle. The problem is width. I can think of a couple skinny 6 lug rear axles that would hold up to a V8, but one of them (FJ40) is offset, the other (late 50's/ early 60's Chevy 2WD) is probably going to be a bit wide. That said, narrowing a rear axle is not hard or expensive. You can have your local hot rod shop cut the rear axle housing and re-weld on the tube flanges for a couple hundred bucks, and Dutchman will cut and respline rear axle shafts for about a hundred bucks each.

 

So go out and get a disc brake Chevy 12 bolt rear and pay the $400 or so to get it narrowed, throw some new perches on it, a new yoke, and you're on the road...with 6 lug.

[Dawa]

i saw a ford 9" on a 620 in the yard one day. the end. aha

[marksm]

I have a 78 datsun with a 5.0 and a t5 trans.everything was put in really good and clean, But whoever put it in did not change the  rear end.  I wanted to know how  strong the rear end is. I have a mustang 5.0 rear end but it is 5 lug. And the truck is 6 lug. How can I change front?

I'm new here too but have been lurking for awhile. I wondered who bought that truck. I'd had my eye on it for month but I felt his price was way too much.

 

Anyway, I'm jealous, if it's engineered correctly. I'd like to see pics..

[Stoffregen Motorsports]

I asked a friend and the S10 Chevy 4x4 axles are 6 lug. They can hold up to a V8 and should be close the the right width.

[Dime Dave]

I purchased a rear end from a Ford Explorer 8.8 (95 - 01) for my V6 521 project parts stash.

 

It has 3.73 gears, 5x4.5 bolt pattern, rear disc and an LSD. Cost me $250. These rear ends have 31 spline - 1.31" diameter axles. Very stout, guys claim they are good for up to 600hp.

 

The stock Explorer rear is 59 3/8" WMS to WMS. I needed 52 7/8" for my 521 or 6 1/2" narrower. The stock axles need to be shortened by at least 4 1/2" to be re-splined.

 

The diff is off center making the axle lengths different by roughly 3", so to center the diff when you narrow the axle to 52 7/8" you need to take 4 3/4" off the driver side and only 1 3/4" off the passenger side of the housing.

 

This longer driver side axle can be reused as it has more than the minimum 4 1/2" being cut off, but the short side doesn't work. If you buy a spare long driver side axle it can shortened by the same 4 3/4" and it will fit the passenger side just right. 

 

This works out perfect on a 521, but might not fit well under a 620 without using more negative offset wheels.

 

Another trick to narrow the Explorer 8.8 by just 3" and will also centered the diff is to buy a spare short passenger side axle and cut 3" off the driver side of the housing and install the short axle in the shortened driver's side of the housing. Doing this you don't need to have any axles cut or re-splined.

 

This will center the diff and narrow the axle to 56 3/8" WMS to WMS. Isn't this close to the stock width of a '78 620 rearend.

 

Not sure is any of this helps.

 

As for the front, Toyota 5 lug hubs (5x4.5) have been swapped with some modifications being done.

 

search Ratsun for "5 lug swap" and several threads pop up with details.