Thread: Series CW&P into Disco 1

To answer your question:
Yes (assuming D1) but you need a spacer ring for the crownwheel - the flange is in a different position on the hemisphere. Spacer rings can be purchased from ashcroft, etc... (or you can swap the whole centre if you are happy with stock)

As for whether you should or not, 4.7 ratios are significantly weaker than 3.54 ratios, as they have a small pinion with fine teeth.

Mick Garner used to run them in his comp RRC on 35's, but was happy to change them when they broke.

It is a question of when not if though...

Originally Posted by isuzurover

To answer your question:
Yes (assuming D1) but you need a spacer ring for the crownwheel - the flange is in a different position on the hemisphere. Spacer rings can be purchased from ashcroft, etc... (or you can swap the whole centre if you are happy with stock)

As for whether you should or not, 4.7 ratios are significantly weaker than 3.54 ratios, as they have a small pinion with fine teeth.

Mick Garner used to run them in his comp RRC on 35's, but was happy to change them when they broke.

It is a question of when not if though...

Hmmm, interesting.

Is it ALL low ratio diffs that are weak or just the series?

what other options do I have if I want to run bigger tires?

Originally Posted by *RR*

Hmmm, interesting.

Is it ALL low ratio diffs that are weak or just the series?

what other options do I have if I want to run bigger tires?

Aftermarket diffs have been designed to improve strength (and probably use better, more advanced materials). The series 4.7 is 47/10 (47 crownwheel teeth and 10 tiny, weak pinion teeth).

The 6x6 perenties have a specially made front CW&P that fits on a 3.54 carrier and is still 47/10 but designed to be much stronger in front application.

Ashcroft have the following:

Originally Posted by Ashcroft transmissions

We have made 5 ratios to give you more choice :

3.50 ratio, with a tooth count of 28/8

3.75 ratio, with a tooth count of 30/8

4.12 ratio, with a tooth count of 33/8

4.37 ratio, with a tooth count of 35/8

4.75 ratio, with a tooth count of 38/8

You can see they didn't go above 8 pinion teeth, to keep the teeth thicker and stronger.

What tyres were you planning to use? In most cases 4.12 or 4.37 may be a better option if you still want to drive on the highway.

Originally Posted by isuzurover

Aftermarket diffs have been designed to improve strength (and probably use better, more advanced materials). The series 4.7 is 47/10 (47 crownwheel teeth and 10 tiny, weak pinion teeth).

The 6x6 perenties have a specially made front CW&P that fits on a 3.54 carrier and is still 47/10 but designed to be much stronger in front application.

Ashcroft have the following:


You can see they didn't go above 8 pinion teeth, to keep the teeth thicker and stronger.

What tyres were you planning to use? In most cases 4.12 or 4.37 may be a better option if you still want to drive on the highway.

I was looking on the KAM website and they have 4.13 and 4.7 for $330aus!

I want to run 35s and maybe bigger in the future (who knows!), freeway speed isn't a HUGE deal as it's not a daily. I worked out with 35s and 4.7s I get 2450rpm at 100, 2940rpm at 120 and 3185rpm at 130. I don't plan on running as high 130, so just under 3000rpm at 120 would put it right in the meat of powerband of the tdi...

at the moment with standard ratios and 30" tires, it running at about 2600rpm at 120 and 2150rpm at 100, which it has trouble pulling.

your thoughts?

Originally Posted by *RR*

...

your thoughts?

My thoughts - Ashcroft are much better designed than KAM...

If that is your goal you may as well stick with 4.75s. However if you want to go larger than 35" it may be an idea to start with a stronger axle assembly....

You have a simpler option that's as strong.. Remove your 1.222:1 ratio transfer box, and fit a 1.410:1 transfer box. Cheers. Simon.

Originally Posted by Sitec

You have a simpler option that's as strong.. Remove your 1.222:1 ratio transfer box, and fit a 1.410:1 transfer box. I have one here I'm not using if you are interested. Cheers. Simon.

My Dad did suggest that exact same idea, but I want to get my low range lower too...

[The 6x6 perenties have a specially made front CW&P that fits on a 3.54 carrier and is still 47/10 but designed to be much stronger in front application.
[/QUOTE]

Not quite correct there. The CW&P is standard 4.7 (47/10) mounted on a custom 4 pinion carrier. The 3.54 4 pinion carrier as fitted to the RFSV's front axle is a different offset to the 6X6. How do I know - I once tried to fit one to my 110 front diff.