Disco 2 Axle rebuild & Final Drive Ratio Change to ~4.1

My D2 has had a lot done to it:
* reasonably comprehensive offroad mods (adding weight)
* new galv chassis - thicker plate than stock so a bit heavier again
* gearbox, tbox, engine rebuild (incuding taller 5th gear from a V8)
* tuning, hybrid turbo, big IC, etc etc, think it's @ ~ 220BHP

I've got my hands on a set of spare axles and want to completely refurbish them, including new diffs, brakes, all bushes.

While I'm doing this the intention is to upgrade to a 4 pin center for the front diff, which is a big improvement over the stock 2 pin. I also want to fit an ashlocker to the rear.

Performance is great at higher revs when the turbo is making most boost, but low down it's a bit 'crap'. Since I'm doing the axle work anyway I thought I may as well change the CW&P ratio to move the gearing back closer to stock.

Ashcroft's HD 4.12 CW&P's look like a good option.

To cut a long story short, should I do the final drive work myself (I'm pretty handy, did all the above rebuild work myself), or should I get someone like Nige at Megasquirt to do it?

Will I need any specialist tools? I've watched some videos online that all suggest special setting blocks are needed to get the pinion height correct...

If you're doing all that, and can afford it, I'd suggest that getting a minimum of the diffs rebuilt correctly is well worth it, and whilst you do it, one of the better upgrades is also diff pegging! It helps stop a lot of the issues with Crown wheel and pinion teeth stripping which makes for a much stronger overall setup for a minimum extra money.

I did my own, but that's 'cos I have no money ... and it's mostly guesswork and careful measurements. If you decide to do your own, then I'd suggest you buy a pegged diff housing as a minimum, the benefit outweighs the costs immensely if you have the money available.

Money is always the issues aint it

Forgot about pegging, is it only really worth doing it on a locking center though?

All the diff failures I've seen on D2's have been down to the cross pin being ejected from the case due to oil starvation... is it just that these WOULD have failed through CW flex but the centre was too weak to even get to that?

That's what they reckon .. go to 4 pin diffs, lockers, whatever, and the weak point shifts.

Mind, everything you add at one area means the weak point shifts again anyway! My thoughts are if you're buying a diff and getting it setup properly, the extra, IIRC, £75 for pegging is a no-brainer and adds a whole heap of strength to the system. OK, HD Crown helps, but it's the bearing mounts that move allowing the crown to move, diff pegging moderates it somewhat even for HD CWP.

OK will keep it in mind, worth doing a job right than doing it twice eh

Bennehboy said:

OK will keep it in mind, worth doing a job right than doing it twice eh

Click to expand...

setting block is easy enough to make, a piece of round bar is a better way of measuring pinion height rather than dti, if you replace bearings using timken shimming is usually about right

jamesmartin said:

setting block is easy enough to make, a piece of round bar is a better way of measuring pinion height rather than dti, if you replace bearings using timken shimming is usually about right

Click to expand...

Might have to pay you a visit with my trailer full of bits James, do a swapsie for a 4 pin

Bennehboy said:

Might have to pay you a visit with my trailer full of bits James, do a swapsie for a 4 pin

Click to expand...

no problem ive still got it

I've snagged to broken 2 pin diffs in casings, so that's a starting point if I DIY this...

In the end I decided to go with a 3.8 ratio change.

Progress so far is on my main vehicle thread starting from here -> https://www.landyzone.co.uk/land-rover/bennehboys-d2-adventure.254514/page-35