Opinion: 91 octane is superior. Especially if you have an MT

Happy Friday.

I’ve been using premium fuel almost exclusively for the 3 years and 38k miles on this truck. About a week ago, I filled up on 89. I’ve done comparisons between the two grades in this truck before, but always paying close attention to noting any differences in performance.

The Taco isn’t my DD, and yesterday I drove it for the first time since that fill up on 89. I was driving up Marin ave here in Berkeley (this is at least a 10% grade with a few stops on the ascent for those not in the area) and the truck was inarguably more doggish - no surprise, but also easily dismissible as to possibly being in my imagination - but, I also noticed I was having to slip the clutch A LOT more to get moving again. Lots of roll back potential on these stops. This time, maybe 3-4 seconds of slip at ~ 2000 RPMs vs. the usual slight bit of throttle, maybe 14-1600 RPMS, and a quick engagement of the clutch. Taking note of this, I considered that I was imagining it all, but after a little more driving around I was confident that the truck was driving differently. Couldn’t figure it out.

I’m a little obsessive about watching my gauges, and when I glanced down at my cluster to check the fuel level despite the fact that I had only put about 10 miles on this tank, it came back to me that I’d filled up on 89 instead of 91. Not much data to go by, but still, I’m convinced that 91 is the fuel for me, if not for a nicer driving experience, to simply make my clutch’s life easier.

That said, I’m not sure that is in fact easier on the clutch. Maybe the higher loads produced by the higher octane fuel is at least equally hard on the clutch.

Convinced but not necessarily right...

Edit: the crickets also vacate my hpfp with 91.

 

You might want to change the title? At least add an "IMHO" instead of such a blanket statement, esp when you're undecided.

These trucks take many miles to adapt to different octane (and tunes). It will drive weird for the first little while.

All that said, 87 has always been best for me. This was confirmed on the stock tune (04B12), the TSB tune (04B13), and now with several OVT tunes. Even more so on the Toyota tunes, using 92 versus 87 netted me a slightly smoother motor and an MPG decrease. It was not worth it. On OVT, there is a power bump on 92 and my MPGs were the same as with the 87 tunes.

So IMHO, it depends on individual Tacos and driving styles.

 

Fair enough. And those are great points. Just an early Friday bs thread.

But what about the crickets?

 

I've noticed with 91 you get a little more oomph and better mpgs. Recently I had an average of 19.5mpg and I'm auto, lift, 285s, front/rear bumper and sliders. However, I did the math and even with the added fuel economy, 87 is still better for your wallet over time.

That being said I fill up with 91 because it's just better to drive.

 

Thats a lot of extra cash out the tailpipe over the past 3 years. Really think its worth the extra cost?

I dont know about The Peoples Republic of CA but here way up in the Northeast you can expect about 20 cents extra between each grade.

 

I had a 1995 Ford F-150 with the 5.0L engine. I always had to run 91 octane so it wouldn't knock. In my newer vehicles, I haven't noticed much difference though. I'm not doubting that you felt a difference but I wonder if one would notice a difference if they didn't know what grade of fuel was in their tanks until afterwards. Kind of like how I notice my truck runs smoother after getting washed

 

Good stuff!

Chirp?

Yeah. For our price and cost difference between octanes, we need about a 2mpg gain to offset the cost. Also roughly speaking and based on 12k/yr, it costs about $100 to gain or lose 1mpg.

 

I’m innocent (see sig)!

But yes the cheapest 91 I can find nearby is about $3.89 with around the same 20¢ difference between grades. The best stuff is ethanol free premium I get in Idaho.

 

That one is just fucking weird. I rarely wash any of our stuff, but it seems to be true even for my bikes.

 

Also, the logic of buying a v6 pickup at around $48k otd, and then neutering it for the sake of saving a few bucks annually is kind of

 

my truck is faster after a nice hand wash. think the wax job makes it more aerodynamic

 

My best advice there is to fill up at Costco and use their Citi Visa card. Gas there is usually $0.40/gal less than the area average here, plus another 4% back on top of that.

 

Try ceramic. + 59 ft lbs and 80 hp

 

Good deal if you don’t have a 20 mile round trip to do it...

 

I'd think the pressure in your tires would affect performance more. You said you hadn't driven it for a while....maybe they were a little lower.

Either that or maybe placebo effect?

 

Only if you're actually neutring it.

Also, not everyone paid $48k for a V6 MT Taco. All in, I will be in it for about $40k when I get the title in hand.

 

Actually a little high at 38-40 psi. Thanks for the reminder!

 

That sucks. At the same time they popped up a Costco a few miles from our house, our favorite Chevron which had the best non-big-box prices around was closed for a light rail station that might get here in another 4yrs.

The Costco CC will get you 4% off at any gas station though.

 

Sorry!