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Discussion Starter · #1 ·
Has anyone here swapped a solid axle into a 720? Any info would be greatly apprecited?(components, labor, cost, difficulty)


Discussion Starter · #2 ·
I have some info, which I received from Andy James (no relation) with regards to his axle and engine swap. He went with a GM motor so the Toy 8" would be compatible and also some Cherokee components were slapped in. There seems to be a bit to much for a single post to handle so if anyone is interested in some of these details let me know and I'll email the file to you?

Chris J.
/wwwthreads_images/icons/wink.gifIf you can't Drive It, Drag It?/wwwthreads_images/icons/wink.gif

Discussion Starter · #4 ·
Yes, I put a 1980 Toyota solid axle in a 1983 720. I am using the stock 720 T-case. A 1980 Toyota SR5 has 4.37 to 1 ring gear/pinion ratio which is the same
as most 720 Nissans. So if possible if going Toyota get a 1980-- but double check your Nissan ratio. The 720 has a divorced T-case that has the outputs very near the center. This centered output means that you will be running your front driveshaft at a double(compound angle). Due to the fact that the divorced T-case sets a long ways back--- the front drive shaft is very long and so the the angle is not very steep compared to other 4x4s--- so a compound angle works
even though it is bad engineering in principle. For a drive shaft, use a Toy, joined with a rear Nissan shaft. The Front half of the Toyota
goes to the Toyota axle, and the Rear Nissan to the T-case. Get an extra Rear output flange off of an extra Nissan T-case and replace
your front T-case flange with the extra. This way the Rear style drive shaft yoke off of a Nissan will bolt to the front output of your
new front drive shaft. In other words you are making a heavy duty drive shaft for the new front out of a Nissan Rear Driveshaft welded
to a Toyota front driveshaft. The shaft and seals in the front of a 720 T-case will allow you to just bolt the heavier rear drive flange right up--
this allows you to build a driveshaft using a Nissan rear driveshaft for parts. The tubing for a Toyota front driveshaft and the Nissan rear
shaft are very close to the same diameter also.

For springs-- if Toyota solid axle is being used, use Toyota springs. I mounted my hanges with shakles in the rear as on a Toyota.
The Toyota frame is wider-- so your hangers and shakle hangers will mount on the outside of the frame. Again this is hard to communicate
in words-- and pictures with dimenstions are needed to make it clear. But due to differences in the Nissan and Toyota Frames,
the Nissan will sit about 3-4 inches higher than a Toyota when the Toyota springs are mounted on the Nissan frame.
I used Toyota V8 conversion springs so I have about 8 inches lift--- could run 38 inch tires.

Care and adjustment is needed to correct the steering geometry --- that is Caster--- after you mount the solid axle.

I built a sub-frame that bolted to the springs and kept them in alignment while I welded the hangers to the Nissan frame.

The Nissan brake cylinder runs the Toyota front disk brakes just fine!
I built cross-over steering---this requires a special passenger side steering arm be built.
But I used the stock Nissan steering box.

I guess I should post some pics

Have fun ---write back with any question


Discussion Starter · #5 ·
Close enough??? A swap's a swap's a swap!

But now that you mention it I think I had a Brain Fart and responded to the wrong post? Someone had asked awhile ago about and axle and engine swap and I said I'd try to find the guy who did it!
Oh well, I don't think I'll loose much sleep over it!

Later Tim!

Chris J.
/wwwthreads_images/icons/wink.gifIf you can't Drive It, Drag It?/wwwthreads_images/icons/wink.gif

Discussion Starter · #6 ·
How did you attach the two drive shafts together? Did you cut off one end of each and weld them together? What did you use for rear springs, for the lift? So stock toyota springs in front will give approx 3in lift? How much wider is the axle on the toyota than my nissan?


Discussion Starter · #7 ·
Re: Solid Axle F.Y.I.

There's a guy on the "For Sale all Other" board with some Dana 44's for sale complete each about $150.00 I think?

If your lookin, that is?

Chris J.
/wwwthreads_images/icons/wink.gifIf you can't Drive It, Drag It?/wwwthreads_images/icons/wink.gif

Discussion Starter · #8 ·
Re: Solid Axle F.Y.I.

thanks for the info Chris, I don't know if I am prepared for it now, but just thinking.

Discussion Starter · #9 ·
Re: Solid Axle F.Y.I

thanks for the info chris, I don't know if I am prepared to do it yet, but I am thinking about it.

Discussion Starter · #10 ·
On Driveshafts--
The Nissan rear driveshaft uses tubing that has a narrowed neck. The narrow slides over a machined plug cast into
the u-joint yoke. The plug is about the same size as the Toyota front drive shaft tubing. The Toyota shaft also uses the same
kind of plug set-up You cut the plugs off of each drive shaft. When you do this you have to remove the welded tubing from around the yoke plugs.
You must preserve the Plugs--- do not say the plug off the yoke. Saw the Shaft apart about a couple inchesbehind the weld that circles the shaft
that attaches the yoke to the shaft. Then do careful hack-saw surgery on the weld to remove the tube welded to the yoke.
Then you have the plugs cleaned up to receive a new piece of tubing that will re-slide over the yokes that will be the right length
to reach T-case to Toyota front-end.

A Toyota front end usually costs 100-300 dollars. A driveshaft about 50-150 dollars. Springs 50-200 dollars

Toyota Wheels have the same bolt pattern as Nissan. But many stock Nissan wheels have smaller hub holes and will not fit over
Toyota front hubs. I did not have a problem because I had aftermarket wheels anyway.

It could be less $$$ to go with dana 44s. It just depends on what is easier or cheaper to get a hold-on in your area.

I had a Bronco front end that I was going to use, but there is a Toyota only wreaker just down the street where I live--
there were a number of solid axle converted Toyotas for me to look at and compare. So I could just go down in one day
and have the Toy Junk guy round-up everything I needed for the entire conversion-- He had done a dozen of them himself
so I could just casually walk around his yard and over a few hours load the parts in a traileron one visit. At this yard the junkman
was also an engineering consultant/ machanic/and wheeler-dealer.
I even had them torch old spring hangers off of a Toyota frame that I cleaned-up and used on the conversion-- I got
brakelines, U-bolts, nuts and all the details in a package deal. So it was easy for me under my personal situation to
approach the task that way. He had about 50 frontends out in a pile, but we had to go after a 1980 model that was at the bottom of a pile three
trucks deep. (The 1980 had the proper gear ratio to match my stock Nissan rearend.)

The Toyota front that I used is about 3/4 inch wider on each side than my Nissan was.

How much lift depends on how you mount the spring hangers ON a stock Toyota, the shakels on the front
are mounted to the Toyota frame through a hole bored midway in the frame. I mounted my shakels on HANGERs
that are welded to the bottom of the frame rails. I did this because the Nissan frame has less curve to it. You need see
a picture or compare the two kinds of vehicles to see. Anyway, the Hangers lifted the vehicle.

I have Nissan Main Springs in the rear with left-over Toyota springs added to the pack for added lift.
The Toyota and Nissan springs are the same width so can be mixed. Mixing springs to build leaf
spring packs is common practice. It is not the best engineering however. Each spring has its own
arch and stiffness that does not match the other springs it is teamed with-- this causes jerky suspension and
less spring life--- NEVERTHELESS it works when you do not have the $$$ for the best springs.


Discussion Starter · #12 ·
I do not know for a fact, But I assume that the king cab and regular cab shafts will be the same.

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