Hi Planenut
We have put a few km on the rebuilt bevel box, and it is almost getting hot ( cold and wet how its mostly been )
We, especially the missus, are extremely happy that the "scream" at 50 to 60 mph has gone and stayed away.
The box is still a bit noisy at town speeds ie 30 to 40 mph but is very tolerable.
Overall very happy with the progress.
However I am now keen to get the box out and review the contact points to see if they have changed much. I fancy that there is room for improvement after this bedding in. Cant be arsed to wait for a 1000 km! To see if it improves.
Now done it once its not so arduous to do it again.
I do believe this is an iterative process and would like to perhaps rig up a test bed set to the "noisiest" rpm which i think is around 2000 rpm of pinion? Ie 60 kph
I rationalise the "scream" as a harmonic of the main gear teeth impacts . The reduction in the roughness of the metal surface ( lapping and super finishing) appears to have dealt to that.
Remaining noise is the actual teeth impacts. Noisey when loaded but quiet when at that mid point of no load on accel or decel. This noise grows with rpm to a max then reduces with higher rpm.possibly due to frequency? Hence me having another look at the contact patterns and gear positions.
Was it worth it.
Absolutely. SWIMBO is much happier on longer trips which means we might be doing some runs if summer gives us more than a couple dry days in a row!
Thanks for the interest
Do you really think it’s speed related? I think it’s RPM specific... right around 3,500. So, more likely to hear it “ in town” at lower speeds than at higher speeds where wind noise takes over.
