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I have an AWD Dual Range gearbox here - its in good condition and I am going to crack it open to change the diff over to 3.7:1 and reduction gear to 1.59:1 and the gearbox has done 271,000kms I was thinking what the best part inside that I should replace while its opened up ie. bearings/seals etc and would it be worth it to replace all bearings etc? (and also what kind of prices am i looking at?)
Cheers
AP

NB - Have L series gearbox for parts that will go in AWD D/R box.

AWD diff ..... I presume your diff has 3.9 ratios. For off-roading, most people change to 4.111 or 4.444 ratios to balance out the fitment of larger tyres. What's your rationale in going to 3.7 ratios?

Here's in indication as to what bearings and seals could cost you:
bearing mainshaft $141
input shaft seal $10
input bearing housing o-ring $7
thrust washer $20
diff seal $10
output diff o-ring $5
speedo drive oil seal $5
4wd selector shaft seal $10
low range lay shaft o-ring $4
rear extension bearing $40
centre diff bearing $85
transfer AWD bearings $25

... and if you want to go silly:
4.444 front crown wheel and pinion set $720
4.444 rear vlsd $450 (second hand)
redline shockproof light gear oil $200

For off-roading, most people change to 4.111 or 4.444 ratios to balance out the fitment of larger tyres

I dunno about that - there's robably what 5 of us that have changed diff ratios in an EJ box? Its not a straight forward job... hence not many people have attempted it.

If your box has high Kms on it then you should replace the rear mainshaft bearing as it will most likely be stuffed and then all the seals as well. You may find other bearings also stuffed. ALso if you are going to use it offroad then why are you going to 3.7?

Maybe I didn't express myself clearly.

Assuming the gearbox work is being done with off-roading in mind and you were going to do the extra work of changing crown and pinions, then most people would opt to go from 3.9 to either 4.111 or 4.444 rather than change to 3.7 ratio.

I agree it's not a common mod due to the extra work involved (lathe, etc).

Fair enough above, At the moment the gearbox is just sitting there, why 3.7? because most of the time it will be used on the road rather off road and will use it as off road behind EJ22.
The other thing I have in my mind was that I'm planning to get an Brumby to restore and planning to use EJ22 or EJ25 N/A with Dual Range AWD - that is why I am having ideas at the moment and looking at possibilities as well.... The gearbox might go in my Liberty and when I remove mine and it might go in Brumby and do same thing!? I dunno at the moment - its a thought at this stage.
Cheers & Thanks
AP