GM 6.5L Turbo Diesel Crossover Problem
Looking for a little more power out of your 6.5L?
The stock crossover can be very restrictive if the inner wall collapses. The stock are double walled... Meaning the inner wall can collapse but the outer wall (what you see) looks fine. People refer to the "golf ball test" to see if their inner wall has collapsed or not, you do this by dropping a golf ball down one side, if it comes out the other end, most likely your inner wall is fine. But if it doesn't... it has collapsed somewhere on the inside.
You shouldn't see any gains from just the crossover upgrade. Although if you have a bad crossover (collapsed or leaking) you may feel or see a slight improvement in your power and/or mileage.
The stock downpipe is also another thing to get done ASAP when you get a 6.5 Diesel that has stock exhaust. The stock downpipe can get pretty beaten up from factory... and aftermarket 3" downpipe is the best to get for these
GM 6.5L Crossover Pipe Comparison