M450 Steer Tire BlowOut

[cmillsap]

(01-25-2015 22:52)dentmac Wrote:  Hi,
Failures have been 2 lefts and 3 rights.

Ross,

As you know, this same Meritor IFS is also fitted to the M380. Although I have no data to confirm, I haven’t heard of this problem happening on the M380. I think that some parts of the Meritor IFS were beefed up on the units fitted to the M450. We also know that BB recalled the M450 and made modifications to lower the weight load on the IFS and front tires.

So the questions that should be asked are: Why is this happening on the M450 and not on the M380? How close are the steer axle/tire weight loads comparing the M450 with the M380? What (if any) are the differences in the Meritor IFS fitted to the M380 versus the M450? Are the alignment specifications the same? Is the wheel cut the same? Is the suspension the same? Is there some modification to the suspension on a M450 that allows too much weight transfer/load on a single steer tire around a curve?

If we can document the differences between the two applications, we may be able to better define the cause.

Chuck