Different ratio diffs on the same truck

[Chchshrek]

Hey guys

Im helping a mate build an ORANZ truck at the moment, just convinced him to go 4wd so we looking at diff options.

Its gonna have massive independent front suspention(aiming at 22inchs travel) with similar at the back.

Already convinced on using a safari Diff at the back, but now looking for an independent front diff with the same ratio. Best we can do at the moment is a Safari 4.37:1 diff with a Bighorn front diff of 4.33:1 . Did the calculations and its a .9% difference, which is smaller than new tyres to old tyres.

Is this gonna mess anything else up? Only offroad racing, should never see tarmac so there should be enough give in the surface that it wont make an appricable difference?

Or do anyone know of a front independent diff with the same ratio as any of the safari/patrol diffs...

Cheers

Shrek

[DieselBoy]

The design doesn't make sense??

You are obviously going to be converting a Safari rear diff which is a solid beam axle to be independant.

Why not do two at the same time so you have one for the front??

Or why not just do the same conversion to the Safari high pinion front diff??


It's been a while since i played with Nissan stuff, but if my memory serves me correctly:

The Locker part number for the front diff from a safari is the same as the rear diff from a Terrano, and which is the same as the front diff from a MK/MQ Patrol, and also the same as the front diff in a GQ.

That would mean that the diff ratio in the front of a Terrano would be the same as the GQ/MK/MQ ratio's. On that Basis, a Terrano IFS front diff would work with the ratio of the Safari rear diff.

Why not use a Toyota 9" rear diff say from a 40 through to a 80 series Landcruiser, then you could use a Surf IFS front diff??

But I still don't get why you would be going to the effort of converting a GQ rear solid axle to be IRS compatible yet are looking for some other way of doing the front end??

You obviously have the skilz to create what ever you can dream up, so why not just make your own front end while your at it??

[Bulletproof]

Some 4 wheel drive tractors use different Ratios and apparently it helps traction.

I can't remember which end has the higher ratio

Cheers Richard

[Chchshrek]

The design doesn't make sense??

You are obviously going to be converting a Safari rear diff which is a solid beam axle to be independant.

Why not do two at the same time so you have one for the front??

Or why not just do the same conversion to the Safari high pinion front diff??


It's been a while since i played with Nissan stuff, but if my memory serves me correctly:

The Locker part number for the front diff from a safari is the same as the rear diff from a Terrano, and which is the same as the front diff from a MK/MQ Patrol, and also the same as the front diff in a GQ.

That would mean that the diff ratio in the front of a Terrano would be the same as the GQ/MK/MQ ratio's. On that Basis, a Terrano IFS front diff would work with the ratio of the Safari rear diff.

Why not use a Toyota 9" rear diff say from a 40 through to a 80 series Landcruiser, then you could use a Surf IFS front diff??

But I still don't get why you would be going to the effort of converting a GQ rear solid axle to be IRS compatible yet are looking for some other way of doing the front end??

You obviously have the skilz to create what ever you can dream up, so why not just make your own front end while your at it??

Hey there

Nope keeping the solid axle in the rear with a 4 link, and independent in the front. went with the safari diff due to width and strength

Didnt realise Terreno's were the same, that would make things easier

We are making own arms etc for the front so can use whatever we can fit if it works.

Some 4 wheel drive tractors use different Ratios and apparently it helps traction.

I can't remember which end has the higher ratio

Cheers Richard

huh, didnt realise that

Cheers for the info guys

Shrek

[DieselBoy]

Hahaha, ya threw me with this:

Its gonna have massive independent front suspention(aiming at 22inchs travel) with similar at the back

Thought you where havin 22" of independant goodness at the rear too!!!!!!

Don't quote me on the diff ratio of the Terrano, I'm pretty hazy on it, but the logic works

[Chchshrek]

Hahaha, ya threw me with this:

Its gonna have massive independent front suspention(aiming at 22inchs travel) with similar at the back

Thought you where havin 22" of independant goodness at the rear too!!!!!!

Don't quote me on the diff ratio of the Terrano, I'm pretty hazy on it, but the logic works

yep ill look into the terrano stuff, makes more sense.

and what i meant was 22inchs suspention at the back as well, not independent.

SHrek

[1MadEngineer]

best option by far is getting the rear IRS subassy from NM or later IRS pajeros. They are 9.5" ring gears and have BIG 34spline axles and huge cvs (well they are strong enough for the DRIVE end of a pajero ). AFAIK they are pretty cheap from the wreckers ~$1k'ish complete. If you are lucky enough you might even find one with a factory locker, or get an ARB. They are available in 3.9,4.1,4.3.....

cheers
Greg

paj vs GU h233

[tallsam66]

Some 4 wheel drive tractors use different Ratios and apparently it helps traction.

I can't remember which end has the higher ratio

Cheers Richard

Maybe its because of the massive difference in tyre size from front to rear.

[IcedJohnno]

Have a talk to Andrew Thomason. he runs Fullsize Performance here in Chch and held the NZ1 title two years ago with his yellow tundra.
I know when he was crewing for rod millen they played around with a taller ratio at the front end I think. Maybe the rear, not sure now. I think the idea was to get the truck to step out to drift thru the corners. A lot of CORR style trucks run like this evidently. Not sure if he has tried this with his own Tundra or not.
I definitely know that the tyre sizes were the same F & R on these trucks.

[Bulletproof]

Some 4 wheel drive tractors use different Ratios and apparently it helps traction.

I can't remember which end has the higher ratio

Cheers Richard

Maybe its because of the massive difference in tyre size from front to rear.

No its nothing to do with tyre size. Apparently it helps a tractors climbing ability.

Cheers Richard

[syche]

best option by far is getting the rear IRS subassy from NM or later IRS pajeros. They are 9.5" ring gears and have BIG 34spline axles and huge cvs (well they are strong enough for the DRIVE end of a pajero ). AFAIK they are pretty cheap from the wreckers ~$1k'ish complete. If you are lucky enough you might even find one with a factory locker, or get an ARB. They are available in 3.9,4.1,4.3.....

cheers
Greg

paj vs GU h233

Hi All

I am new on this forum and joined in to get some news abotu this buggy using pajero IRS in teh front. I am working on the same idea so any feedback would be great . My big concern is the steer angle of the rear CV joints as they were not designed for that, i would guess it gives a very limited steering angle and therefore a very wide turning radius but i might be wrong

Regards

[daynehrn]

Not sure about the cv turning angle but when we were converting a safari rear end for 4ws our original plan was to use a front diff in the rear but found whichever way it went in it was going to load the wrong side of the crown wheel and pinion.
You may have the same problem in reverse putting the rear diff in the front.

[syche]

Hi,

Yes sure i would be driving on the coast side but that won't be a problem, well i think.

The diff is really big and should be able to handle that easilly, especially since the max load would be up hill so not so much weight, torque into it.

On the other end, while backing up, pulling someone or reversing up hill, i would be on the right side full strength when it is needed .

I just really wander about the max working angle for the CV's?

I saw this paj came with 4.61 gear in some v6 engines today, that is perfect for my application

[syche]

Is 1madengineer still here?

Would be great if anybody had a rear half shaft with CV's and could measure the max working angle