Originally Posted by
Apco1
I would think that cross pins see a large amount of force. Especially the thicker the fluid is. Under full acceleration all the force in the center diff is being put on the cross pins is it not? Correct me if I'm wrong but if those pins were to sheer off, the diff housing would spin but not the out drives. I just don't see the advantage of a composite cross pin, give me steel.
Many on the team haven't been running steel cross pins in a long time, but rather the aluminum TKR5149A. They still show no wear after a year of use.
If the pins were to completely sheer off, you would be correct if there was a vacuum inside the diff and the gears didn't sit in recesses. The thicker the diff oil, the less force will be on the pins themselves. However, with multiple points of contact, and teams like Durango doing this even in full 8th scale with the higher torque that comes with it, I don't think we're likely to see a problem. In practice if the crosspins sheer off, your diff would lock up rather than free spin. I'll still be using the Aluminum part I listed above though, for the reason I mentioned before, as I've been running in my original SCT410 and my EB48.2.