Diff swap

[Rod Rocket]

I have a 2002 GU and have just fitted a Chevy Optimizer 6.5lt V8 diesel from Brunswicks. Is there anyone in WA willing to swap my 4.3:1 F&R diffs (212,000kms) for their 4.1:1 diffs please? Mine are in excellent condition and I wish for the same in return. Cheers.

[MudRunnerTD]

Damn. I have heard 3.9s are best suited. You should get good coin for the 4.3s and sghould get 4.1s cheap.

[MudRunnerTD]

@peeved MB and Eviltwin all have this engine. Not sure what gears they have.

[PeeBee]

I have 3.9 N/A optimiser in GQ. - from @peeved Darren - ya big fat fingered goose! I know a guy who went as high as 3.7's and the 10% overdrive on the turbo, but basically was useless on the highway - could not pass anything without dropping down 2 cogs.

[MudRunnerTD]

I have 3.9 N/A optimiser in GQ. - from @peeved Darren - ya big fat fingered goose! I know a guy who went as high as 3.7's and the 10% overdrive on the turbo, but basically was useless on the highway - could not pass anything without dropping down 2 cogs.

Hahaha bloody fat fingers and auto correct.

[PeeBee]

no worries Dirtwobbler

[the evil twin]

3.9 in mine when it was still the 5 speed but I think Brunny recommend the 4.1 in the 4L60 family of auto's.

Now that mine is also an auto I found it was a bit tall with 35's but 33's driven off the 4L85 works

[Rod Rocket]

Hey MudRunner TD, 3.9s are a bit tall for towing a caravan

[MB]

4.3s currently in mine also after removing the 3.9s as they were too tall for our hilly highways here. I reckon 4.1s and reduction LR gears would be perfect too as the 4.3s are too low on the flat open 100km 5speed stock manual box driving 35s.
EDIT: Have thought about Marks 5th gear upgrade too that could work for leaving the 4.3s in there: https://www.marks4wd.com/mfk730.html

Sent from my iPhone using Tapatalk

[the evil twin]

IMHO if you run the standard 5 speed box...
3.9 for standard to 'small' 33's cruising
4.1 for 33's towing or lots of 4X... or... 35's cruising
4.3 for 35's if you want a tug.

Having said that everything is a compromise esp if the car is a daily or worker and depending on genuine tyre size IE some 'small' 33's are under 32 actual

[Rod Rocket]

MB, I also sussed out the 5th gear upgrade but was told that the rev gap between 4th and 5th was too great for towing a caravan and I would be constantly pulling it back to 4th, therefore eliminating the advantage.

[the evil twin]

6L80e for the win... point it, floor it. :1062:

Expensive tho :frown:

Wish I'd had the cabbage at the time but the 4L85e will just have to do for now while I dream about a Supercharged P400 / 6L80e

[MB]

poindexter mate, is it confirmed that a P400’s sump will fit in our GU’s at bump stop?
My new Bannana fibreglass bonnet should fit the charger well, lol :-)


Sent from my iPhone using Tapatalk

[MB]

I have a 2002 GU and have just fitted a Chevy Optimizer 6.5lt V8 diesel from Brunswicks. Is there anyone in WA willing to swap my 4.3:1 F&R diffs (212,000kms) for their 4.1:1 diffs please? Mine are in excellent condition and I wish for the same in return. Cheers.
East-West Postage may be a bugger mate, although my 3.9s kindly swapped out by Patrol Apart - Victoria were I believe shipped back across to Brunswick possibly. Chat to the blokes there and here to see if some 4.1’s can make there next Nullabor pallet run.


Sent from my iPhone using Tapatalk

[Rod Rocket]

Thanks MB,will ask