Power Service w/Cetane Boost, Stanadyne, Lucas Fuel additive are all good. Mdub707 spoke correctly regarding turbo housings and what you should do with respect to Turbo performance. If you ain't throttling hard from time to time it is going to build up soot and clog. At least once or twice a day I make it a point for mine to sing at 30+ psi. Then I know it is working right...

 

I strictly use Opti-lube additives. They have an XPD formula that is pretty sweet. It rated second highest in independent studies for lubricity, which I feel is pretty important with ULSD. The only thing that beat it was 5% bio diesel. Stanadyne did almost nothing for lubricity.

My stacks are 6" mitres.

 

where can i get opti-lube? is that something autozone would have or walmart?

since i have a 8' bed on my truck i thought i should go with 8" miter cut stacks. worried 6" might look too skinny in my long bed.

 

Stack size is up to you. I'm not a fan of really large stacks. I was going to do 6" mitres or a single 7" mitre on mine, ended up finding a good deal on the dual stacks so there it is. Big stacks need a big lift/tire combo to look proportional IMO. If I had an 8' box I'd prob do a single 6 or 7" stack and a toolbox personally.

Opti-lube, I've only been able to order direct. The local places wont have it. www.opti-lube.com

 

you can buy the Revive turbo and engine cleaner in the us now for $275.00 2 bottles or $175.00 for 1 bottle and you don't have to remove the turbo and dosent damage any parts or gaskets, would be worth trying