Hey guys,

Okay I really need someone who knows their diffs, I'm in the swapping parts stage between 2 of my xr8's one preparing to sell and one to keep.

I recently bought an 1996 EF xr8 manual
I had a look at the diff and the yellow tag says it's a 3.23

My other 1996 EF xr8 Automatic has a 3.45

I just went through 9 hours of hard labour pulling out both complete diffs and swapped them around put the 3.45 into the Manual car expecting a noticeable difference in acceleration and honestly think it was pointless doesn't seem much faster ��

So my question is, as it is a stock engine and the only mods I'd be looking at doing budget wise is better air intake, full exhaust system with extractors, and a j3 tune chip was hoping the diff change would wake up the engine a bit but is there another diff gears I should consider instead?

i put a 3.45 into a AU that had a 3.23 .... noticed a bit of differance & it's a stock 6 auto wagooon. so i'm surprised you didn't notice any differance??

[/quote]


i put a 3.45 into a AU that had a 3.23 .... noticed a bit of differance & it's a stock 6 auto wagooon. so i'm surprised you didn't notice any differance??[/quote]

I'm pretty sure that 3.23/3.45 gears in a AU 6 cylinder wagon have single spinner diffs not LSD like XR's 6/8

But yeah I only noticed a little difference

From factory it should've been the same diff as the automatic I would think.

Nah definitely 3:23 for manual and 3:45 for the auto both option 20 police cars... Maybe that had something to do with it?

Nah, I think all XR's 6 or 8 had 3:45 to 1 std ratio. An OPT 20 chaser would require the better take off acceleration you would think.

I wonder if something silly like a recoed 3:45 centre's been put in an axle tube with a 3:23 sticker - maybe the original tube was damaged.

Counting the number of rotations or reading the crownwheel stamping are probably the only sure confirmation ways.

Yeah I was wondering that too maybe the diff centre has been changed and the gears aren't what the housing suggests it is. But from the looks of things under the car both diff axles look like its never been touched and as is from factory so there you have it both genuine OPT 20 chasers and Manila fitted with 3:23 and auto with 3:45

With the 3:45 now in my manual I have noticed a small differance in acceleration, but I think I'll wait until my other engine mods are done first see what power it's making and then consider the upgrade to 3.7's or 3.9's...

Anyone else with info on how these gears feel with manual stock 5L engine let me know cheers

3.23 to 3.45 is such a tiny difference numerically, so im not surprised you couldn't feel much difference.