720 transfer into 620

[RyanC]

Anyone used a 720 transfer case in a 620 chassis?

 

Have free y60 patrol front and rear axles..different...brakes etc

 

Something different in mind than the usual build.

 

Sas.and bags...8 inches of ride height adjustment hmmm

[datzenmike]

 

The 620 frame was shot so I used an '81 720 2wd long bed frame. Toyota SAS on the front. T 100 transfer case. F-150 leaf springs re arched all round.

 

4X4 frames are different than 2wd ones. Here's why...

 

 

Output from the transfer case runs right through the 2wd frame cross member.

[Stoffregen Motorsports]

T100 Nissan, not Toyota T100.

 

Not totally pertinent, but here's a 4x4wire thread on the T100 t-case - http://4x4wire.com/forums/ubbthreads.php/topics/433898.html

 

Are you going to use radius arms like the Y60? Or custom links? Make sure you get the caster close, or it will be dangerous to drive on the road.

[datzenmike]

1 hour ago, datzenmike said:

 

 

  Toyota SAS on the front. T 100 transfer case. F-150 leaf springs re arched all round.

 

T 100 transfer case separated by period from Toyota SAS. 

[RyanC]

15 hours ago, datzenmike said:

 

The 620 frame was shot so I used an '81 720 2wd long bed frame. Toyota SAS on the front. T 100 transfer case. F-150 leaf springs re arched all round.

 

4X4 frames are different than 2wd ones. Here's why...

 

 

Output from the transfer case runs right through the 2wd frame cross member.

 

Thanks Mike so is that member modified or a 720? Looks like a cut rebuild affair.  I will be hoping to find a truck at the wreckers and get any cross members mounting plates etc.

 

I did think of running a 720 front diff and what not but like the idea of the sas I think.

[RyanC]

14 hours ago, Stoffregen Motorsports said:

T100 Nissan, not Toyota T100.

 

Not totally pertinent, but here's a 4x4wire thread on the T100 t-case - http://4x4wire.com/forums/ubbthreads.php/topics/433898.html

 

Are you going to use radius arms like the Y60? Or custom links? Make sure you get the caster close, or it will be dangerous to drive on the road.

Thanks mate.

 

Yes there is a company here who makes upgraded modified version ...superior engineering...they do a few version and all.help sort the castor issues.

[datzenmike]

The 4x4 frame is different. If you have a 620 or 720 2wd it will be in the way.

[RyanC]

So modify it is?

[datzenmike]

Definitely. I got a section of 12" water pipe and welded it in place.

[Stoffregen Motorsports]

Have welder, will mod.

[datzenmike]

The blue tipped wrench or the wire feed wrench.

[RyanC]

Lol thats pretty much where I was heading when I saw that pic.

 

Once the ute is running i can focus on chasing down the transfer and measuring up the front end.  Main issue is where the diff and frame come together.  Again hot knife and welder can make clearance.

 

I think I will need to put some flares on her up front based on initial measurements.

[datzenmike]

The 720 4X4 driveshaft is a slip yoke so it can extend or collapse to make up for slight differences in the transfer case/differential mounting

[Stoffregen Motorsports]

There are extended slip drivelines available too. For short shafts with lots of height differential between the t-case output and the diff flange. Trail Gear used to make them, and they were ok, but you couldn't beat the price.

[RyanC]

Thanks both of you will be checking slip yoke lengths etc once I know my full travel.

 

Seemingly it's simple enough...famous last words.  🤣🤣

[datzenmike]

The driveshaft between transmission and transfer case is splined into the transmission so there is some leeway there. The driveshaft from transfer case to differential is a slip joint so there's leeway there also. Some careful measuring to locate the transfer case properly and you should be good.

 

I used only a tape measure and a washer on a string for a plumb bob.

[RyanC]

👍👍

 

Have plumb bob.. will measure.  Thanks Mike  🤞 she is running soon so I can start organising what bits are needed.

Edited June 20, 2022 by RyanC

[RyanC]

So might have found someone wrecking a 720 4x4 but believe its a diesel.  Assume transfer case gearing is the same between petrol or diesel?

 

Asking for transfer/crossmember and all shafts.

 

I believe it has a 5 speed which would be nice but the diesel starter is other side? And something about speedo?  Gearing probably different petrol to diesel from reading another thread here.  But low first gear probably handy.

 

 

[Crashtd420]

3 minutes ago, RyanC said:

So might have found someone wrecking a 720 4x4 but believe its a diesel.  Assume transfer case gearing is the same between petrol or diesel?

 

Asking for transfer/crossmember and all shafts.

 

I believe it has a 5 speed which would be nice but the diesel starter is other side? And something about speedo?  Gearing probably different petrol to diesel from reading another thread here.  But low first gear probably handy.

 

 

Can you get the whole truck....

Your best bet would be to use the 720 frame and put your 620 on top to achieve a 4x4 620.... I assume that's what you're after.. 

[datzenmike]

Diesels were never put in 720 4X4s. Well not by the factory at least. 4X4s and diesels were never automatics.

 

 

Get a 4X4 and put the 620 body on. Models should match KC to KC or long box, short wheelbase to short wheelbase.

[620slodat]

 

The only problem with that suggestion is the country/state you are in (different countries have different laws). Since you are in Australia is changing to an older body legal? Check with the Department of Motor Vehicles to see if it is legal, and what hoops you need to jump through to do this if it is legal.

 

The 620 frame and the 720 frames are almost identical. The major difference is the tie rod difference.  The tie rods are configured differently from the 620 to the 720. The steering box and idler arm is on the inside of the frame on the 620, while the 720 steering box and idler arm are on the outside of the frame. The 720 box and idler being on the outside will give you more room in the engine bay. This may not be a concern for you if you go SAS. The only other difference is if you have a long bed frame and a standard body, or the reverse, and the bed will have different frame/bed mounts for the front bed mounts. Otherwise all the body/bed mounts are the same between standard or King Cab. The bed may not be a problem for you since it appears you have a flat bed.

 

Don

[RyanC]

Will be doing a SAS with patrol axles.  So no need for full frame or body swap.  The axle swaps look easier than a body swap or both.

 

Not sure if the diesel was a 4x4 here might just be the 5 speeds are from diesels.  Don't have to do a 5 speed swap but here down under there are lots long drives. Just he has one to sell.

 

 

[datzenmike]

What engine/transmission is in the 620?

[RyanC]

L20b and 4 speed.  L20 will probably stay and may end up with efi and turbo.  Or I leave it with 4 speed for now and do a vq swap and 5/6speed down the track. 

 

Will see what he wants.  Apparently transfers 1 needs shift circles and one one is missing counter shaft.  So has offered 2 for 1 so I can rebuild 1 good one.  Figure bearings and seals...can I get speedo gear housings or is this a pain?

[datzenmike]

If transmission is F4W71B then swap the front case half onto the diesel FS5W71B to convert it to bolt up to the L20B. As is, the diesel 5 speed won't bolt up.

 

Your 4 speed speedometer pinion, (probably) will fit the transfer case. The one in there might happen to match your differential/tire size.