I am considering upgrading the turbo on my truck with a Garrett power max. is a special tune required? some people say you need one, others say the turbo is a stock replacement... I am confused

 

You do not need a updated tune but it really helps.

 

I've heard it both ways so it probably depends on the individual truck. FICM tuning helps greatly also.

 

Without a tune you just won't see the benefit of the upgraded turbo, and it might be a hair more laggy than stock. I noticed it more on my '03 that has an Inferred EBP strategy, but since your truck uses the Exhaust Back Pressure sensor, it should be able to compensate for the larger turbo.

 

I already have a super chips economy tuner, but all it does is use an older factory tune to increase mileage.

I am also concerned about increasing boost and power levels on the stock head gaskets.

 

The PowerMax is a little laggy in stock form on my truck, it does not increase power just by bolting in, that is done through tuning if that is one of your concerns.

 

It does add a little top end with stock tuning since it moves more air at higher RPMs.