I recently noticed a strange behavior in my 250 SD w/ auto/V10. When it is fully warmed up, it seems to grab when I take off from a stop...as if it was going in gear just as I step on the throttle. It feels as if something is locking it up just as I throttle up. It does not do it if I throttle up real easy...or at least it isn't noticeable. This is not apparent when it is cold. Does any one out there have the same behavior? Other than that it runs great.

 

I've had vehicles do that if they were low on trans fluid.