Prado 120 rear diff installation

General discussion of basically anything Hilux related

Prado 120 rear diff installation

Postby shamat on Thu, 04 Jun 2020 4:34 +0000

Hi All,

It's been a while since i posted anything, but I've embarked on a new project and thought I'd check with the brains trust here regarding some potential issues I can foresee.

I'm putting a Prado 120 rear diff in order to gain the benefit of rear disc brakes.
I have the housing and have confirmed my e locker, 4.56 ratios centre will bolt in.
All existing mounts have been cut off, leaf spring perches and bracing welded on.
So far so good.

Now the areas of potential issues I can see are:
1. ABS - Is the teeth count on the ABS tone/wheel speed rings the same on the KUN26 and the 120 Prado? I.e. will I have issues with the ABS that I need to address?
2. Hand brake cable - the position where the hand brake enters the backing plate is about 2 inched further back and down. How have others extended the hand brake cable?

I'm installing an adjustable load proportioning valve for the front/rear brake bias and simply splitting the single bake line to both the left and right rear brakes (as it is with the drum brakes).

Has anyone here already completed such an installation and if so, what advice/comments can you provide regarding the issues identified above?

Thanks in advance,
Shamat
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW


 

Re: Prado 120 rear diff installation

Postby HK1837 on Thu, 04 Jun 2020 4:41 +0000

On a Holden when we fitted rear discs you had to modify the master cyl, not sure it’s the case on a Hilux.

Get your housing checked for straightness too. Seen plenty of them warp once welded, it is common with 9” housings.
HK1837
 
Posts: 1060
Joined: Tue, 17 May 2011 1:31 +0000

Re: Prado 120 rear diff installation

Postby shamat on Thu, 04 Jun 2020 5:09 +0000

HK1837 wrote:On a Holden when we fitted rear discs you had to modify the master cyl, not sure it’s the case on a Hilux.

Get your housing checked for straightness too. Seen plenty of them warp once welded, it is common with 9” housings.


Thanks for the feedback.
Already have an upgraded master cylinder and double diaphragm booster. Did that when I put the 120 front brakes on :)
Diff was welded by a diff specialist who ensured it stayed 100% straight.
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW

Re: Prado 120 rear diff installation

Postby hiluxxury on Thu, 04 Jun 2020 5:10 +0000

Edit: you beat me to making this post....

I've braced a couple of housings which is where many see problems with warping due to too much heat. Short welds are the key to keeping heat down and reducing the risk or warping. I cant imagine there would be mucj problem with welding a seat for the leaf springs.

There is a bit of slack along the hand brake cables. Less on the drivers side but there might be enough.

You can look up part numbers for the abs rings or call a wrecker to check for you?

X2 with HK1837 on the mastet cylinder issue.

Does the abs system remove the need for a proportioning valve?
I might be wrong.

2005 SR Hilux 1KD - SOLD
2009 BMW X5 - destroyed by a hail storm
2012 Range Rover Sport SDV6 - SOLD
2015 Ford Ranger
User avatar
hiluxxury
Moderator
 
Posts: 1584
Joined: Sun, 20 Dec 2009 4:16 +0000
Location: Tasmania

Re: Prado 120 rear diff installation

Postby shamat on Thu, 04 Jun 2020 5:20 +0000

hiluxxury wrote:Edit: you beat me to making this post....

Does the abs system remove the need for a proportioning valve?


I'm assuming it does as the vehicle already had ABS and an LPV.

with regards to the part numbers, I've spent hours searching online and cant find anything definitive.

Ive gone as far as finding a picture of the hilux one and manually counting the teeth. Can't find an straight on image of the Prado 120 ABS ring though.
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW

Re: Prado 120 rear diff installation

Postby shamat on Tue, 16 Jun 2020 5:37 +0000

For those interested, it turns out the Prado 120 doesn't use a tone ring for the rear axle ABS. The sensor reads off the rear wheel bearing. I'm just hoping the number of revolutions on the bearing matches somewhere close to that of the tone ring on the original Hilux rear setup.
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW

Re: Prado 120 rear diff installation

Postby hiluxxury on Wed, 17 Jun 2020 5:48 +0000

Thanks for that - not at issue I had come across yet. Very good to know.

Let us know how it goes.
I might be wrong.

2005 SR Hilux 1KD - SOLD
2009 BMW X5 - destroyed by a hail storm
2012 Range Rover Sport SDV6 - SOLD
2015 Ford Ranger
User avatar
hiluxxury
Moderator
 
Posts: 1584
Joined: Sun, 20 Dec 2009 4:16 +0000
Location: Tasmania

Re: Prado 120 rear diff installation

Postby shamat on Wed, 17 Jun 2020 5:53 +0000

hiluxxury wrote:Thanks for that - not at issue I had come across yet. Very good to know.

Let us know how it goes.
@Hiluxxury, Have you done this type of conversion previously?
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW

Re: Prado 120 rear diff installation

Postby hiluxxury on Wed, 17 Jun 2020 6:55 +0000

No, but I looked at it closely for the easy disc brake conversion. I dont have abs anyway, so I wouldn't have considered this problem.

I was also concerned about becoming of the prado 120 diff club - something I would have resolved with a locker but at the time it was too much cost and I've since been distracted with other shiny things.
I might be wrong.

2005 SR Hilux 1KD - SOLD
2009 BMW X5 - destroyed by a hail storm
2012 Range Rover Sport SDV6 - SOLD
2015 Ford Ranger
User avatar
hiluxxury
Moderator
 
Posts: 1584
Joined: Sun, 20 Dec 2009 4:16 +0000
Location: Tasmania

Re: Prado 120 rear diff installation

Postby shamat on Wed, 17 Jun 2020 7:52 +0000

hiluxxury wrote:I was also concerned about becoming of the prado 120 diff club - something I would have resolved with a locker but at the time it was too much cost and I've since been distracted with other shiny things.


Already have an eLocker that will fit straight into the 120 housing :)
I've been told the 120 wheel bearing setup is also stronger, so that's another benefit.
User avatar
shamat
 
Posts: 202
Joined: Mon, 21 Jul 2014 6:49 +0000
Location: Western Sydney, NSW

Re: Prado 120 rear diff installation

Postby hiluxxury on Wed, 17 Jun 2020 8:26 +0000

Yes, the bearings are certainly better the 2005-08 hiluxs but about the same quality for the 08+ hilux models from what I can gather.
I might be wrong.

2005 SR Hilux 1KD - SOLD
2009 BMW X5 - destroyed by a hail storm
2012 Range Rover Sport SDV6 - SOLD
2015 Ford Ranger
User avatar
hiluxxury
Moderator
 
Posts: 1584
Joined: Sun, 20 Dec 2009 4:16 +0000
Location: Tasmania

Re: Prado 120 rear diff installation

Postby Hulix26r on Thu, 05 May 2022 8:07 +0000

What was the end result with the abs side of things. I'm looking to do the same mod.
I've done it with a 105 series rear diff in a 79 series but no abs so was a easy conversion.
Hulix26r
 
Posts: 27
Joined: Wed, 25 Aug 2021 7:41 +0000
Location: Perth WA


Return to General Discussion

Who is online

Users browsing this forum: No registered users and 9 guests