I have fitted larger tyres to my 150 4motion, and find the gear ratios are now out of sink. You have to be careful not to stall in first when pulling away quickly like at a roundabout and ideally be doing 70mph to change into to top (6th) unless travelling on the flat. Otherwise I can hear the engine beginning to labour. To rectify this I am going to have the gear ratios changed by Seikel in Germany which will lower first and second gear by 18% and 3rd - 6th by 10%. This will hopefully improve the drive ability when towing and off road . Due to the ratio change the gear change indicator will be obsolete. Hence wanting to delete it.
The engine has been mapped from 150 -192hp which has helped, but still find you have to slip the clutch on soft ground.