[Climber76]

I have a nearly new 2009 double cab 4x4, automatic transmission, towing package. It has two quirks I don't like, and I was wondering if others had the same issues and/or if these indicate problems.

First, when I release the brakes, there is a clunking sound from the rear. Sometimes the clunk only happens on initial acceleration, not at the moment I release the brakes. It seems to happen mainly when I have stopped fairly quickly or on a downgrade. I suspect that what I'm hearing is the overload springs fetching up on the longer leaf springs as the axle shifts with torque. But seems like it shouldn't do that. Any other ideas of what could cause this? I have not had any of the other transmission/drive line issues others have described, other than that the transmission occasionally goes into lockup mode a bit harshly after I accelerate onto the freeway.

Second, when I go around corners around town, or go over a large speed bump, the transmission downshifts two gears and the engine races for a second when I begin to accelerate again. I'm driving very gently, trying to get the best mileage I can, so the transmission isn't responding to actual load. It seems to be anticipating a load that isn't there. Seems completely unnecessary and is very irritating. Is this normal? Dealer says yes, but I'm wondering if there's either a problem with an accelerometer, or a programming issue.

Otherwise I like the truck, though fuel economy could be better (getting 17 mpg average in Albuquerque in-town mix of freeway and street driving).

Thanks for any insights.