MK5 Crown Wheel & Pinion

[steverk]

I am looking at fitting a MK3 crown wheel and pinion with a higher ratio into my MK5 differential - I have heard that there are differences between MK3 and later MK5 axles I think to do with half shaft diameters but its not clear if this includes differences with the crown wheel and pinion parts.

I would retain the current differential housing and planet gears etc and just swap the crown wheel and pinion gears.

Would this work or are the gears different???

Any pointers on this would be much appreciated

Steve

[cherniy_chack]

Someone at this Forum offers diff 4.1.
What kind of gear do you have and what interests you?

[MinorMatt]

So long as its the same axle type cw&p interchangeable

[cherniy_chack]

Axes type H MK3 and MK4, MK5 are not interchangeable.
Replacing defa requires some works that are not very complex, but require expertise and knowledge.
I was engaged in such a replacement, I know.

[steverk]

My current axle is 4.56:1 the standard ratio. The van never carries any weight. To change the crown wheel and pinion will require (possibly) revised shims and or 'crush' washer to ensure proper meshing but the original star gears and housing will remain as per original. Going for a 4.11:1 ratio will ultimately provide an extra 10 MPH at 70-80MPH although I tend to drive it at around 56MPH in lane 1 following the LGVs. A 4.11:1 diff' will give 2-3 MPH increase (at 4,000RPM) in first, 3-4 in second etc. up to 5th gear with a drop of around 300 RPM at 60 which although doesn't sound much is audibly noticeable.

[cherniy_chack]

Hello, steverk.
Replacing the gearbox 4.56 by 4.1 or 4.11 will give an increase in speed with the same engine speed by 11%, and increase the real mileage by 11% with the same odometer reading. This should be taken into account when speed limits are limited and fuel consumption is calculated.
The fuel consumption will decrease by approximately 5%.
Reducer (diff) 4.11 was used on MK3, gearbox 4.1 on MK4 and MK5.
Reducer 4.1 can be installed on your MK5 without any problems.
If you find a reducer 4.11, then to install it on your MK5 you will need
interchange the boxes of differentials and gears.
On the gearbox MK3 4.11 it will be necessary to install a differential box from the MK5 4.56 reducer, while leaving the gear wheel MK3.
It is not difficult.
Then it will be necessary to adjust the clearance in meshing.
This is also not difficult.
Then install the gearbox on the axle.
Reducer = diff.