You will never here it knock because the sensors and computer stops it.
A few years ago I was up in altitude and running 85 octane blended for the thin air and because of a wrong turn dropped down to 1K, it never knocked just lacked in power. Went right back into the altitude and everything was fine.

Denny

 

It won't actually knock as the sensors would have the system pull some timing to avoid that. Only way to see it is by data logging it while it's running as far as I know.

Components that make up the fuel. Higher octane fuels use less of the lower end stock and more higher refined stocks.

Lots of EGR issues in some 90's model cars running just regular when premium would have helped it run a lot cleaner. But what idiot would run premium in a corolla? LOL.

Griz

 

I have a 2013 SCLB 350 and 2014 CCSB 250, both 6.2's.

The '13 is my work truck and has almost 200k. Mostly used in WY and UT.

The '14 is a grocery getter/pavement princess.

The '14 has almost 55k. Both have never seen anything but 85 octane.

No knocking with either of them and no major issues with either. Regular maintenance

I am at about 4500 feet.

 

I can run regular in it just driving it if not going to tow with it, but it's all it's used for. You'll never have knocking on these motors with the sensors designed to adjust for it.

I run the 91 you guys have up at higher altitudes when towing versus the 93 octane we have at sea level.

I had a 1970 big block chevy 3/4 ton once that ran best on blending 93 and 87 for a 90 octane mix. It would ping on 89, but not blending it to 90.

It had been running on propane when I got it. 6 mpg on propane. 10 on gasoline.

Griz

 

The topic of octane and power rating of the engine is often misunderstood.

The higher the octane, the more resistance to pre-detonation; we all know that. Running "more" (advanced) timing allows the engine to capitalize on a bit more "burn" relative to the piston position in the bore before TDC. Yada yada yada ...
The real thing to understand is that this has two effects"
1) efficiency
2) power at peak
As for the efficiency, we'll probably never see any real tangible assessment at the pump; just too small to notice even though it may be there. It can probably be seen in the lab tests, but on the street we'll just not be able to quanitify it with proof. 'Nuff said.
As for "power", the only time we would notice is at peak power in the rpm (typically WOT). The advance of timing can make for a bit more force in the power stroke. This is why we see the 6.2L, as well as many other Ford engines (EB engines in many Ford vehicles) get a tad more power "rated" in the sales brochure. Running more advance in the timing makes for a greater force PRIOR to TDC. The speed of combustion is fairly consistent; the flame front for most gasoline blends is fairly stable. Therefore, to get "more" of the force to happen before TDC, we have to advance the timing relative to the flame front happening. More advance means more time for a more peak cylinder pressure prior to TDC. This can have an effect of perhaps 5-10hp (depending upon displacement, volumetric filling, etc). BUT .....
You'd only get this effect at higher rpms and close to peak power. For any given load, your foot will press on the pedal until your brain is happy with the acceleration result. But you won't realize (or more properly stated as utilize) full power unless you go WOT. Because for any load below WOT, you foot would compensate for the "need" of power. So the only time we really get any benefit from FULL POWER is at WOT, and that can be improved via more timing advancement. But unless you're at or near WOT and between peak torque and peak power (aka the "power band"), it really is moot.

I'm perfectly happy running 87 octane. My 6.2L runs fine. It does not "need' higher octane to run OK. It make a tiny bit less power by using lower octane fuel. How much lower? I have no idea, but a reasonable estimate would be 5-10 less "hp". So maybe I'm only getting 375 hp instead of the premium-fuel-rated 385 hp. But unless I'm at WOT pulling a heavy load, I'm never going to sense that loss because my foot would compensate to satiate my brain's demand.


My initial point in my previous post was that if you're filling up your gasser truck with premium fuel, it will certainly more expensive. High octane fuel is not a requirement for the safe and reasonable operation of the engine. It's only "needed" if you expect to get every last ft-lb of torque that the engine is "rated" for.

 

I'm jealous!

 

Jim,
Are you, or anyone else, aware of any reliability issues with the 6R100 vs. the 6R140? I can't understand why Ford would introduce a new transmission for the "lighter" end of the line-up while still producing the original transmission for the "heavier" end unless they found a way to save enough money in material & construction costs in the new transmission to justify the engineering, tooling & production costs of adding an extra transmission to the lineup.

 

There was a recall for a minor mechanical issue (parking pawl?) with the early 6R100; otherwise I've not head of any issues. I have read many compliments on the AT, especially how it complements the updated 6.2.

FWIW, my 2019 OM says the 64100 AT holds 13.9 qts. of ATF, and the 6R140 holds 17.4.

I have no doubt that the 6R100 costs less to produce than the 6R140. The 6R140 was introduced for MY2011, and has proven to be an excellent AT. We were very pleased with the 6R140's behavior in our 2017 F350 6.2, and we're looking forward to the same powertrain in our new 2019 F350.

Regards,
Jim / crewzer

 

I've not seen any Ford spec that states or implies that premium fuel is required for the 6.2 to develop full rated power. However, the 2017+ OM does include this discussion:



Ford's 6.2 HP spec is certified to SAE J1349. My take is that the engine can develop something near full power from 87 AKI fuel under ideal environmental circumstances (i.e., ~600 ft above sea level, moderate air temperature, low humidity). Portions of Death Valley in the winter come to mind. However, if the engine is thermally stressed (towing uphill into a headwind on a hot day while running the A/C), the ECU will retard ignition timing to avoid knock. This action will reduce fuel economy and available power.

The anti-knock properties of higher-AKI fuel should allow the ECU to return to optimal timing and restore performance.

HTH,
Jim / crewzer

 

While the new 6r100 has proven reliable, a few members have reported a shutter when reversing with a load. I can't remember any 6r140 issues. It has been rock solid. I think the reason for the swap was less for cost reasons and more for the fact the lighter rotating assembly and slightly different ratios make a difference behind the gas motor, especially with the more common 3.73 rear end gear. It's hard to tell how much of difference because of the bump in torque at a considerably lower rpm. After all, the 6r140 was designed for the hi torque 6.7. Other than the torque converter and clutch materials, there are no deference between the diesel/gas versions. The 6r140 is definitely a Beefer unit, and probably the reason it is retained in the f350, as many fleet/commercial dually trucks are treated pretty hard. I know the old v10 flatbeds we have are way overworked.

 

FWIW - I've never used anything but 87 in mine. Towing 10K in 95-100deg heat over some of our mountain passes and never lacked any power or felt like it was holding back.

I waited for the 17's to come out and waited to see if there were any year one issues. I got the f350 for a couple reasons, one was the 6R140. It's rock solid and I have yet to see temps over 206deg.

 

You still going to be in the Valley or are you gonna wander a bit first?

Griz

 

I run premium in everything I own except the 2013 5.0 F-150 Lariat. Run 87 in it.
Both Harley's are big bore/stroker motors running over 10:1 compression, and over 210 ccp,so premium in them.
Dodge Charger R/T 5.7L Hemi running a 93 Octane performance tune. DUH!
2011 F-250 Lariat CCSB is the "tow only" vehicle sitting in driveway the rest of the time. Premium in it too.

I buy premium when I fill my gas cans as lots of fuel draining from working on Harley's other than mine.
Generator/lawn mower/weed eater all running premium too this way.

Griz

 

The 6R140 might be used in the F350 because of the power takeoff possibility rather than for any concerns about longevity.

Many posters focus on the cost savings for Ford on the 6R100. It may be cheaper to produce but I don't think that there are any concerns for longevity. And I think that the 6R100 may be more suited and responsive for the 6.2. So, I do believe that there are positive reasons for the 6R100 in the product line.