kberg:
We have plenty of r480’s and none of them run the same.
Some run like a 480 should, and some run fine, until going up a grade.
The not so good ones seems to run fine, but just don’t make the torque when it really needs it.
Then there are some that can not decide if it is a good or bad running one, it might pull like nothing else in the morning, then get lazy on the way back 
They have been to the dealer umpteen ties, but as usual, it is driver error, or nothing wrong with their amazing product.
I am thinking egr valve myself, we have had issues with those, and it seems to run ok for a week or two after they have been “fixed”
Yeah the 13l are really something. The first of them has a recall on the engine block. Faulty casting, but it will show on high oil consumption. The intercooler has extended warranty, may have something to do with the sky high boost pressure they are running. Cracks quite easy and can be quite hard to find the leak.
VGT turbo may get stuck some times resulting in narrow power band. The 13l should pull best around 1000-1200rpm
Was out on a test drive after the block change with a mechanic sitting in the passenger seat with the test computer. At 1000rpm it already had full boost pressure according to the computer.
Also think it doesn’t have enough cooling. Feels like it looses a lot of power on long hills, mean like ex RV15 from Stryn east with 49t gross I was down in low 2 and it almost stalled in the swings.
The XPI injection was a rush job and was long way from finished when the 13l was released.
12l on the other hand works like a dream and there is no problem with tuning on those engines. Paddborg guys pushing almost 600hp from them without any problems.
Luckily the last 13l is gone from us now. Driving a tuned 620 at the moment and that really is something. Holy hell it pulls.