6.5 engine RPO code??

[Rpf207]

On my air intake box is the emisions tag/engine ID tag etc. it reads LRS 6.5. I can't find any info anywhere about this RPO code. Anyone have any clue?

[DmaxMaverick]

It isn't an RPO code. The RPO's for 6.5L turbo Diesels is L56 and L65 (LD and HD, respectively). "LRS" is an emission control system code, but I don't recall what it means. What vehicle is the engine and airbox in, and are they original and in original configuration?

[Rpf207]

Ohhh ok. My truck is a 1999 c3500hd 5 spd. I knew the HD 6.5's were L65 but didn't realize that was an emissions code on the air box. So it got me wondering if I had another version of the 6.5.

[DmaxMaverick]

The 3500HD (of old) is a different animal, as compared to the Light Trucks typically discussed here (but not discouraged in the least). It is classified Medium Duty, and is subject to very different emission standards.

[Rpf207]

Yes! Exactly why I bought it. Didn't feel like paying the price of a new dually for a dump truck or buying just a regular dump. I needed something beyond the norm. I also need 4wd so I had to find and buy the rare Dana 70f 10 lug to do so. So how does this emissions difference come into play? More power? Less power? Not that it's a performance motor. But it only has 39,000 original miles, ex Gov. Truck.

[benaustic]

I had a 1994 Chevy 3500HD. If I remember right, it was rated 190 hp just like the 1995 K2500 I have now. The truck was tough as nails. Wish I could have it back...

My only complaint? It rode so rough I had to wear a helmet and a bra to drive it.

[DmaxMaverick]

I'm not aware of any power differences between the 2500HD/3500 and 3500HD. As said, they were rated at 190 HP. The emission standards were for classification purposes (Light Truck vs. Medium Duty), but I don't believe there was any real difference from L65 to L65, of any like-year.