What Type Of Diff Do I Have????

[WazzaVN]

Tch tch tch.

Any BW78 differential centre will fit into the BW78 IRS differential housing.

Not a hard job to change centres. Just need to know what you are doing.

Where the axles go into the carrier on an IRS centre is different. I know they're both 28 spline but IRS axles won't work with live axle centre.

 

[K-BAGZ]

Where the axles go into the carrier on an IRS centre is different. I know they're both 28 spline but IRS axles won't work with live axle centre.

Care to explain?

Because I beg to differ, as I did an IRS centre change early this year. Full rebuilt with new stub axles and retaining clips.

 

[Clutchy]

A live axle center don't have the grove for the retaining clips on the drive shafts as far as I know.

 

[WazzaVN]

Care to explain?

Because I beg to differ, as I did an IRS centre change early this year. Full rebuilt with new stub axles and retaining clips.

My mate was wrecking his vn a couple of years ago and I was going to grab his centre off him. I was going to get g&j diffs to put it in for me but they said a live axle centre is no good in an IRS diff. I haven't actually pulled appart a Borg warner live axle diff. But played with some older ones. The way to pull out the axles is to push the axle into the centre and remove pull out the c clamp with some pliers. I have built an IRS diff and you just pop the axles out with a pinch bar. Also most online diff shops are selling live axle and IRS diff centres seperately. Indicating that there's a difference.

I read a thread on this forum written by immortal called 'diffs, all you need to know' or something like that. He said that IRS centres can he used in live axles but live axles can't be used in IRS. Again because of how the axles go in.


http://forums.justcommodores.com.au/v6-development-modification/71234-diff-all-you-need-know.html

There you go they don't have the groove in them for the stub axle.

 

[Deuce]

Some please correct me, but does:
Any VX - VZ diff is interchangeable (all are IRS)
Any IRS rear - up to end of VT is interchangeable,
If any diff swaps are being made between those models, the drive shaft flange will require changing?

is that all the variables, or have I missed something?

edit: sorry, read whole page and then posted question. should have refreshed instead and post #24 may have answered my question

 

[K-BAGZ]

Mmmm... Interesting findings and statements.

 

[Not_An_Abba_Fan]

Just to elaborate on what I was saying, it's all about the word used after "higher" or "taller". If it's "higher ratio", it means shorter gears, but if you say "higher gears", then it's taller gears.

I quite often hear people say high ratio for taller gears, when I correct them it's like "huh?"....

 

[brocksta05]

You're after something like THIS

Just thought I'd chuck this up for ya.

Yeah I was watching that one but forgot all about it and missed out. It sold for bugger all too. :doh::doh:

 

[brocksta05]

It's true. Just like lower ratio gearboxes and all. I just say shorter to save confusion.

Don't get 3.45's they suck and you'll be dissapainted. Atleast get 3.7's. I've got 3.7's in my vp and sometimes wish I had 3.9's. And I've got 3.9's in my ss and wish I had 4.11's haha! M78 LSD centres are good too. Better than m80 anyway. There's a couple of online diff stores that sell tight centres for about 250 - $300 if you want to source One yourself. Has to be IRS though. Live axle centre won't go in.

I'm thinking 3.46's because it'll give it a bit better acceleration than the 3.07:1 but hopefully won't bring the revs up too much higher when doing 100-110 because I do a few long trips aswell (hence my car just clicked over 298000 today)

 

[Cashman_309]

I have 3.45's and sit just above 2k rpm at 100. Instant fuel economy is about 0.5 ltrs per hundred kms better than when I had 3.07's