Hey Bill, do you mind elaborating on the broken rear axles? Are they magnafluxed and inspected for cracks regularly? Is the rear suspension of your car adjustable, and if so, do you check the axle plunge every time you adjust? If you are willing to share, I am willing to learn! I understand if it is more proprietary as well
Happy to share, We run Summers brothers axles and in the last four seasons we have not had a failure.... not one! We service and inspect every race. Definitely no change in the plunge or suspension adjustment that would cause this, My thought at this point is that we shock loaded one of the shafts and it broke. Once you break one with the spooled rear end the other one is soon to follow. Like I said this is not a recurring problem so we will repair it and continue on our merry way.