AU IRS 3.45 LSD in to a Solid Beam

**rayban76** · 09-04-2014, 05:35 PM

Does anyone how if the IRS 3.45 LSD will come out of the Final Drive unit and bolt in to the Solid Beam housing?

I am looking at putting a 3.45 LSD in to my wagon and have found an IRS 3.45 LSD

Regards
Ray

mcfly94 · 09-04-2014, 06:21 PM

im pretty sure the lsd is a totally different carrier

**rayban76** · 09-04-2014, 06:28 PM

Hmmm not sure, I know that you can put the IRS LSD in to a non LSD IRS, just not sure about putting it in the beam axle

Sox · 09-04-2014, 07:21 PM

As far as I'm aware, they are not interchangeable.

**rayban76** · 09-04-2014, 07:25 PM

I know the solid beams can take the LSD because mines got one in it at the moment but it's not a 3.45 ....
The solid beam manual talked about the LSD as well...
Hmm wonder if it's worth buying it and seeing, and if not selling it off ....

mcfly94 · 09-04-2014, 08:14 PM

just ring up a diff shop in Adelaide? theres a few renowned ones here, they'll know, or even athol park ford wreckers would know

**rayban76** · 09-04-2014, 08:16 PM

Thanks mcfly94, I might do that tomorrow just to make sure.

**auIILTD** · 10-04-2014, 10:20 AM

Ray, come and borrow my IRS diff and see if the centre will fit into your live axle housing. It is a 3.23 single spinner, but it should at least highlight if the centre will fit?

Stu

**rayban76** · 10-04-2014, 02:26 PM

Quote:

Originally Posted by mcfly94

just ring up a diff shop in Adelaide? theres a few renowned ones here, they'll know, or even athol park ford wreckers would know

Thanks for the idea, just called and the IRS centres are a different setup and do not bolt in to the Solid beam housing ...

Damn ........

Cheers for the offer Stu, now just need to find a 3.45 LSD from like a series 1 XR8 as they had the solid beam

XRGhia · 10-04-2014, 02:36 PM

Ahahaha, they do bolt in. I've got a set of 3:45's from an AU IRS center in my EF wagon. Did the diff center, and pinion swap on my driveway.

Can always get an XR ute diff complete and just bolt it in. AU1 XR8's still got IRS too.

**rayban76** · 10-04-2014, 02:38 PM

Quote:

Originally Posted by XRGhia

Ahahaha, they do bolt in. I've got a set of 3:45's from an AU IRS center in my EF wagon. Did the diff center, and pinion swap on my driveway.

Is that right .... Hmmm thanks Tony, I couldnt see why they wouldnt but when I was told that I was like oh ok ...

Is yours the LSD ?

Hmmmm ok this gives me more hope hahaha

Cheers Tony

XRGhia · 10-04-2014, 02:44 PM

Yeah it's an LSD center.

I doubt there's a difference between EF and AU. Even my standard axles went back in no issues.

**rayban76** · 10-04-2014, 02:45 PM

Quote:

Originally Posted by XRGhia

Yeah it's an LSD center.

I doubt there's a difference between EF and AU. Even my standard axles went back in no issues.

Ok cool thanks Tony, I'l just get it and try it then... 'IF' for some reason it doesnt fit i'll just sell it but I coldnt see why it wouldnt.

Ray

XRGhia · 10-04-2014, 03:00 PM

The only thing though, is that getting the diff center out/in is a tight fit, so be careful. I used a rubber mallet to slowly tap the LSD 3:45's in, and some rope to rip the old one 3:23's out.

What I did was brakes off, handbrake released, then the 4 bolts (14mm off memory) that hold the axle in.

I didn't have to remove the handbrake gear at all though, left that in place. Drain the oil before pulling the axles just incase.

**rayban76** · 10-04-2014, 03:03 PM

Quote:

Originally Posted by XRGhia

The only thing though, is that getting the diff center out/in is a tight fit, so be careful. I used a rubber mallet to slowly tap the LSD 3:45's in, and some rope to rip the old one 3:23's out.

What I did was brakes off, handbrake released, then the 4 bolts (14mm off memory) that hold the axle in.

I didn't have to remove the handbrake gear at all though, left that in place. Drain the oil before pulling the axles just incase.

Yeah the rear whel bearings have only recently been done so its the 4 hex bolts to slide each axle out of the retainers.

I'll give it a try, will put a new seal in the housing at the same time

**rayban76** · 10-04-2014, 03:11 PM

Ok so have called another diff place and have been told they are a very easy swap to do and the IRS set will bolt straight in.

Thanks again for the advice Tony.

Ray

GK · 10-04-2014, 05:43 PM

Sounds like a ripper mod!

All the best with it.

GK

**rayban76** · 11-04-2014, 06:33 PM

Quote:

Originally Posted by GK

Sounds like a ripper mod!

All the best with it.

GK

Thanks GK, i'll make sure there are plenty of pics up on my thread when I do it

Sox · 11-04-2014, 06:56 PM

I've rebuilt both types of these diffs, live axle and IRS, though I haven't had them in pieces side by side.

For some reason I understand they aren't interchangeable, but now reading this thread further, I want to see for myself.

I have a live axle setup that I'm in the middle of reassembling right now, and I have a IRS center sitting in the shed.

I'll take the hat off the IRS center tomorrow, eyeball it, and take a few measurements while the hat is still off the live axle.

How does that sound...

**rayban76** · 11-04-2014, 06:59 PM

Quote:

Originally Posted by Sox

I've rebuilt both types of these diffs, live axle and IRS, though I haven't had them in pieces side by side.

For some reason I understand they aren't interchangeable, but now reading this thread further, I want to see for myself.

I have a live axle setup that I'm in the middle of reassembling right now, and I have a IRS center sitting in the shed.

I'll take the hat off the IRS center tomorrow, eyeball it, and take a few measurements while the hat is still off the live axle.

How does that sound...

Some pics would be awesome if you could as well sox,

I spoke with a diff place here in canberra and he said they are interchangable centres, and actually had one of each he just finished building for someone

Ray

Sox · 12-04-2014, 02:14 PM

I can't eyeball a difference between the spools.

However the cones and spider gears must be slightly different as the IRS half shafts lock into the cone/spider gear with a 'C' clip.
I can also see a slight difference in the cones from the small clearance inspection hole.

My guess is an IRS spool might go into a solid housing, but probably not the other way around, as the IRS half shafts wouldn't be able to lock into anything.

Without completely disassembling the IRS spool I have here, I can't really tell for sure.
(I don't want to disturb this unit).

In a nutshell it possibly works the way you want to do it, however if it were me I'd probably try to source the correct parts as there is definitely a difference.

For your info, I picked up 2 x LS spools from Ebay a couple weeks back for $200.
I've already rebuilt 1 (machined cones/shimmed) and plonked it in my work ute with 4.11 gears, it works perfect.
The other one will go into my XR6 wagon when I find some 3.7 or 3.9 gears.

**rayban76** · 12-04-2014, 03:24 PM

Thanks for that info Sox, yeah the diff guy said to me the same thing that the IRS would go in to a solid beam but not the other way around so your 'eyeballing' seems pretty spot on lol

Cheers
Ray

5.0 ED · 13-04-2014, 07:19 PM

The cones are different, you can use the IRS cones in a live axle, however live axle cones don't have the circlip for the half shafts.

The diff gears and LSD center and completely interchangeable into the live axle housing, I have done it before.

mcfly94 · 13-04-2014, 07:54 PM

so if go buy a complete irs lsd 3.45 centre I can swap into my live axle diff?

5.0 ED · 14-04-2014, 09:44 PM

you can swap the center and gears yes, you need to use all the shims from the donor diff, which means knocking the pinion bearing shells out of the housing and using them and the shim that is behind it in the live axle diff.

As long as its a Ford BTR78 series diff that is.

Rfordsfun · 03-12-2015, 11:27 PM

Hi fellas, So what set up does the 2002 au3 forte have ? I have my AU2 fairghia 3.45 lsd IRS, and am looking to transplant into a au3 2002 forte, plus do the lot interior electrics heater box, dash ecu bcm, engine trans, or will the double wish bone bolt straight to the au3 forte ? cheers. slapped a tree, bounced front wheel to back wheel, and mashing my rear quarter dog leg, fun times. expensively stupid.

thanks in advance merry xmas HNY!!