speedo corection

[tassie wombat]

Gday I'm just about to fit some 4.3 diff gears to my '04 4.2 tdi wagon,but I think I may have the wrong part ?? Thanks
http://i490.photobucket.com/albums/rr269/reefrunner/IMAG0009_zps68cd2e1c.jpg
http://i490.photobucket.com/albums/rr269/reefrunner/IMAG0013_zpsb8396d13.jpg (http://s490.photobucket.com/user/reefrunner/media/IMAG0013_zpsb8396d13.jpg.html)

[my third 256]

Marks adaptors make speedo gears to fit some gear boxes. You need to use a GPS to work out how much your speedo is up or down, give them a call and they will tell you what new gear ratio you need to correct it. They even have electronic boxes for some vehicles. You can set them up to work with various tyre diameters if you have a number of different tyres (road / mud) that you may use. Give them a call.

[Stropp]

gday mate, heres what you are looking for courtesy of the evil twin,





Diff ratio Tyre size Speedo gear (pinion) Part Number 32703 - 31G 17
Change last 2 digits (in boldface) for gear you need using the table below.

Be aware that is manuf spec so speedo will probably overread slightly IE at 100KPH GPS the speedo will possibly be 103 maybe 104 KPH as req'd by ADR's

Your diff ratio will be on the vehicle build plate

3.9:1 Ratio
TyrePinion
31 16
33 15
35 14
37 13

4.11:1 Ratio
31 17
33 16
35 15
37 14

4.375:1 Ratio
31 18
33 17
35 16
37 15

4.625:1 Ratio
31 19
33 18
35 17
37 16

[tassie wombat]

thanks for that strop,thats the part number on the box the pinion came in,so it must be the right one?? I was under the impression that it was only the plastic gear that goes on the pinion shaft and sits behind the larger gear pictured that I need???