LRR tire or lighter weight tire?
 

I have been wondering which would be better for fuel economy and safety, a LRR tire or a lighter tire? I have been looking into tires for my truck and I have found LRR tires are about 5 lb heavier than regular tires. I might be able to offset this additional weight by getting alloy/aluminum rims to replace the steel I currently have. Please let me know your thoughts. Thanks.

T rating instead of H.
has a lot more than weight to do with being a "better tire".

What tirss exactly are you looking at? I don't recall such a diffeeence when I was looking but I was not looking for truck tires. Haha. In general, LRR is going to be better for fuel economy. That is the point, after all.

You need to read some of the tire threads to get a better sense of what is involved.

Specifically, the term "LRR" is a relative term, not an absolute one. It means "compared to other tires with similar treadwear and traction characteristics, this tire has a lower rolling resistance."

Plus safety doesn't really play into the weight and RR game - except to say that tires with cap plies are less prone to failure - but cap plies only weigh 1 or 2 pounds - and only add a little bit to RR.

And there can be HUGE differences in RR that are largely undetectable unless you actually test for it. That is, weight is not a good clue.

Weight, especially in the tires, only really matters for stop-and-go driving (or on REALLY rough roads, but on roads that rough I'd worry more about flat protection and grip than efficiency). For cruising, once you're up to speed 20 pounds doesn't make much difference considering the total weight of the vehicle (especially if it's a modern pickup/SUV).

Smooth hubcaps can make quite a big difference at highway speeds though. I recall seeing a thread on here of a pickup gaining a few percent from those alone. I recommend sticking with the steel rims if they can take hubcaps, and making or buying some smooth hubcaps for yourself. Lighter rims can actively hurt aero as, from what I've seen, they tend to have more open spoke patterns that catch more air.

And LRR tires are, unfortunately, fairly ambiguous as to what their improvement is, as CapriRacer mentioned; there's no standardized measurement. If you need new tires anyway it probably wouldn't hurt to go with LRR's, but ditching a new set of tires to get them will probably more than negate your savings from the LRR's.

As long as you have extra space in the wheel wells, picking tires with a larger outer diameter will also generally help fuel economy, all else (like tread pattern and tread width) equal. Narrower tread width also helps, though there you can get into the issue of less traction.

Thank you all for the advice. Looking at the tires again, I realized deejaaa was right. One is a P245/70R16 and the other was a LT245/75R16. The construction differences alone would make up the weight.

I'll definitely look into other ways I can make up for some of the inefficiencies of this truck. An aero cap and electric fans look like they would have better results than tires.

I think I'd agree with that. Also, pickups seem to get pretty good results from large air dams, due to how aerodynamically 'dirty' their undersides are.