My last Pete 386 had the DEF tank on the right side and it was a real problem. I can tell you that the hose at a FJ pump definitaly does not reach across. It is about 3' short. The only way is to pull through the pumps the wrong way round if possible or buy DEF in jugs but thats expensive. My new 386 has been specified with the DEF tank on the left which is a whole lot better.
Your freind who bought the 389 and specked it had to sign a build sheet before the truck was ordered. It would specify how big and where the DEF tank was located. It should have been no suprise when the truck came in. Peterbilt prides itself in being able to custom order trucks how the owner wants them and it should be no suprise the DEF tank is part of that. For whatever reason right side DEF tanks are very popular at our shop almost the norm for log and plow trucks. All trucks will now have DEF as IH is using a Cummins made systom soon on their Max force engines. Also they will have Cummins enignes in their chassis again. Like sombody above said the reason the fill cap is so low on the tank is to allow for expantion when freezing.
When you spec a Pete the dealer can print a nice diagram on Prospector that gives an illustration of the tank layout. We see about 50/50 on RH/LH DEF tank slection. Often an APU install or plow equipment, etc. on a vocational chassis will dictate where the DEF tank can go. Peterbilt goes so far as to put a message on the Spec sheet that says "You have selected a Diesel Exhaust Fluid (DEF) tank mounted on the right hand (passengers) side of the vehicle. Note, some retail fuel distributors have chosen to standardize on DEF dispensing pumps oriented to the left hand (drivers) side of the vehicle. Please verify selection for DEF tank mounting" What more can they do? Many regional carriers are not concerned as they fuel/fill DEF in their yard and side is not a concern. OTR I can see left hand being more convienient. Yes, Peterbilt can be "backwards" on some things, but this is not one. Don't blame the factory for your your friend's choice of location!
Many big fleets do that for safety. In a breakdown on the side of the road, they often tow out a good tractor to swap. With the 5th wheel release and landing leg crank on the right, you are not in traffic. The other thinking on this is when many trucks are in the dock at the same time, if someone is pulling out or backing in next to you while you are hooking, you are on their drivers side and easier to see.
Maybe keep an empty DEF jug to refill at the pump? Don't let the tank get too low, it won't be too much of a chore, and a lot cheaper than buying individual jugs. Maybe refill it while the fuel's pumping.
