There are two trains of thought on that:

1. Some say the lack of sulfur is a lack of lubricant and you have to add something back in place of it or be prepared to replace failed injection system components.

2. Some say the fuel folks add something back already and the fuel is plenty "slippery", no harm will be done, and you don't need an additive.

I believe the second choice, and have had no problems at all with my 98 Volkswagen TDI.
If the new fuel isn't as slippery or more so than the old version and it causes problems someone might be liable for the damages. I'm betting they don't take that risk and the fuel is still OK to use as is.

But there a bunch of folks who insist the first option is absolutely true..

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
---All pictures---
"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-