1lw 3406e

Ok, long story here, I have a good friend who has a glider kit with a 1LW 3406E 435hp that is looking to get better fuel mileage. I will provide arraingement number and other things as I get near the truck again. I know it has a Borg Warner charger but can't verify part number of the charger:thankyou2: to determine which housing wheel ect. Complaint is barely 5.4 mpg, low power ect. Does anybody have a parts list for say 550hp and 6.5-6.7 mpg. Not looking for a knock down power house. This is a fleet truck with a fleet driver. He has considered swapping in a 60 series that I have built him (BK60 500hp) but I am dead set at getting this Cat up to par. I believe it has 57' injectors in it but that's about it. Any advice on which cam, cylinder kits, injectors and files would be greatly appreciated.

If you mean fleet driver how I mean fleet driver, leave it alone.

What is the truck used for and how are the rest of the specs?

Fleet driver meaning guy who drives it is only guy who drives and has been driving it for 4 years. He's an older gentlemen who doesn't raw dog it.. Only truck in fleet I have had to overhaul front differential yet so that says alot. Owner has 30 trucks. It's a 13 speed, 11R22.5s, I think 3.55s if I'm correct. It's a Freightliner Coronado series. We have a few Petes with C15s but they were supplied by Fitz and do ok 6.1-6.2 mpg.

Truck pulls dry van never sees more than 78k gross either.. Occasional flat bed use too