Looking at a new 2012 LR4

dcwhybrew

Adventurer
Buy the LR4, don't worry about the gas grade.

LOL, kind of funny to read a whole discussion on use of premium vs regular unleaded gas when you're paying $20-50k for a car (depending on which model and which model year). Seriously, there's a $0.20 difference in grades, that $3 per tank if you fill up at the quarter tank mark. Occasionally for work, I will drive 1252 miles round trip. I looked at buying a different vehicle so that I could run regular unleaded vs premium. For the 1252 mile round trip, I'd save about $26. Forget about the premium vs regular, it's an academic discussion and really doesnt matter. (By the way, every LR product since the RR's introduction to the US has required premium gas) True consideration points between the LR4 and LR3 - options and performance.

I really like the LR4s performance. Man, that is a smooth car to drive. I love it. I really hate giving the LR4 loaner back when I get my oil changed. However, the LR3 was a huge leap ahead of the previous models in terms of reliability and performance. The only things I do not like about the LR4 are: wheel and tire size (primary dislike), the location of the terrain response controls (vs the LR3) and the loss of the grab handles on the front driver and passenger seats that were on all of the Discoveries and LR3.

It's hard enough to get a decent all terrain tire in a similar stock size for the LR3, the LR4s with their standard 19 & 20" wheels make it impossible. I liked the LR3 terrain response controls better than the LR4. In the LR3, they're easier to reach and manipulate while underway. Yes, you cant see them as well in the LR3 but you dont have to reach for them in the LR3 like you do in the LR4. The reaching pulls your head down and eyes off the road. And, I just like the grab handles for people getting in the backseat. I hate it when people grab hold of my headrests when they're trying to get in to the back seat of my car or truck.

Anyway, if it were my choice having owned two LR3s and driven the LR4....buy the LR4 and enjoy the heck out of it. Fortunately since LR has exponentially improved their product quality with the LR3 era vehicles, you can't/won't go wrong with either purchase. I just prefer the performance of the LR4 over the LR3.
 

perkj

Explorer
regarding 87 vs 91, you can always stock up on and carry some octane booster prior to heading somewhere where you think the higher octane won't be available and for whatever reason you have a requirement for the maximum stated hp numbers by the manufacturer (read into this unless you're racing your LR3, there is no need).

The reality is any modern electronic fuel injection will make the proper timing & fuel adjustments, regardless of whether the motor has high compression or not, to ensure there won't be any knocking or denotation....though there will be a loss in hp. The talk above of carbon build up and plug fouling is nonsense unless you're running carburetors, old mechanical FI (i.e. Bosch CIS), or very old EFI (which had very limited fuel/timing maps). With the adaptive and learning ECUs in the modern EFI systems, some might argue that it will take some time for the ECU to recalibrate itself from 91 fuel down to 87 and that you should be easy on the gas pedal for 100 miles or so. While this may have "some" merit, you can simply disconnect the battery to clear all of the adaptive/learned sensor data....this will have the ECU start learning/adapting immediately to the new fuel. If you have an OBD2 tool, it can be used to reset the senor data as well without having to disconnect the battery.

The net is the "required" octane value on modern EFI cars is only there allow them to claim their maximum hp performs numbers.
 
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Daryl

Adventurer
LOL, kind of funny to read a whole discussion on use of premium vs regular unleaded gas when you're paying $20-50k for a car (depending on which model and which model year). Seriously, there's a $0.20 difference in grades, that $3 per tank if you fill up at the quarter tank mark.

This is a thread about overlanding on an overlanding forum. Fuel cost is not the issue being discussed. It's whether premium is required or not as a concern for availability in overlanding situations where fuel choices may be limited.
 

ipgregory

Adventurer
you can simply disconnect the battery to clear all of the adaptive/learned sensor data....this will have the ECU start learning/adapting immediately to the new fuel. If you have an OBD2 tool, it can be used to reset the senor data as well without having to disconnect the battery.

Not the case on GEMS equipped vehicles (not sure about Bosch and later trucks). The adaptive values cannot be cleared with a battery disconnect (earlier 14CUX trucks can) or an OBD II Scan tool. It requires a proprietary computer to clear.

Also remember these are European vehicles designed (initially at least) to run on Euro Fuel with much higher octane ratings even than US premium. The newer models are most likely equipped with fuel maps that go as low as US regular gas but I wouldn't be so sure all the older ones do. My 98 D1 for instance will soon let you know not just if you run on regular gas but also if the brand of gas (additives mix?) is something it doesn't like.

So a blanket statement that all modern (LR) vehicles with EFi will adapt for and run on lower octane fuels I would say is something to be cautious of if you have no personal experience that it is the case in the LR world at least.

Cost is not a stated factor for the OP but since we're discussing this from an Expo standpoint, range should be considered. These are big, heavy, un-aerodynamic vehicles and are not over powered to begin with, any reduction in power is going to cause more gas to be used and more gas to need to be carried when away from civilization. I have seen differences of up to 20% or more in loss of fuel consumption on long trips when running gas the trucks don't like.

You won't hurt it to run the odd tank of lower octane fuel but you are not doing yourself any favors really. If you have to head into the boonies and your concerned at the availability of higher octane gas, carry some Octane booster as has been mentioned. You can get quite far if you add a bottle every other tank or so and it doesn't take up much room. But I wouldn't try and drive around some parts of the world in anything other than a diesel anyway.

YMMV

Ian
 

baja5337

Observer
regarding 87 vs 91, you can always stock up on and carry some octane booster prior to heading somewhere where you think the higher octane won't be available and for whatever reason you have a requirement for the maximum stated hp numbers by the manufacturer (read into this unless you're racing your LR3, there is no need).

The reality is any modern electronic fuel injection will make the proper timing & fuel adjustments, regardless of whether the motor has high compression or not, to ensure there won't be any knocking or denotation....though there will be a loss in hp. The talk above of carbon build up and plug fouling is nonsense unless you're running carburetors, old mechanical FI (i.e. Bosch CIS), or very old EFI (which had very limited fuel/timing maps). With the adaptive and learning ECUs in the modern EFI systems, some might argue that it will take some time for the ECU to recalibrate itself from 91 fuel down to 87 and that you should be easy on the gas pedal for 100 miles or so. While this may have "some" merit, you can simply disconnect the battery to clear all of the adaptive/learned sensor data....this will have the ECU start learning/adapting immediately to the new fuel. If you have an OBD2 tool, it can be used to reset the senor data as well without having to disconnect the battery.

The net is the "required" octane value on modern EFI cars is only there allow them to claim their maximum hp performs numbers.

I'm sure there are some Land Rover FSE's that would disagree with your statement about carbon build up being nonsense. There are multiple SSM's regarding this topic for the 5.0 motor and even the old Buick v8 motor was susceptible to valve stick from continued use of poor quality fuel
 

perkj

Explorer
Poor quality/dirty fuel does cause carbon build up. Octane level does not equate to the quality or how dirty gas is...dirty gas is a factor of the refinery, the additives, the tanker its transported in, the tank at the station, etc.
 
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perkj

Explorer
Not the case on GEMS equipped vehicles (not sure about Bosch and later trucks). The adaptive values cannot be cleared with a battery disconnect (earlier 14CUX trucks can) or an OBD II Scan tool. It requires a proprietary computer to clear.

Also remember these are European vehicles designed (initially at least) to run on Euro Fuel with much higher octane ratings even than US premium. The newer models are most likely equipped with fuel maps that go as low as US regular gas but I wouldn't be so sure all the older ones do. My 98 D1 for instance will soon let you know not just if you run on regular gas but also if the brand of gas (additives mix?) is something it doesn't like.

So a blanket statement that all modern (LR) vehicles with EFi will adapt for and run on lower octane fuels I would say is something to be cautious of if you have no personal experience that it is the case in the LR world at least.

Cost is not a stated factor for the OP but since we're discussing this from an Expo standpoint, range should be considered. These are big, heavy, un-aerodynamic vehicles and are not over powered to begin with, any reduction in power is going to cause more gas to be used and more gas to need to be carried when away from civilization. I have seen differences of up to 20% or more in loss of fuel consumption on long trips when running gas the trucks don’t like.

You won’t hurt it to run the odd tank of lower octane fuel but you are not doing yourself any favors really. If you have to head into the boonies and your concerned at the availability of higher octane gas, carry some Octane booster as has been mentioned. You can get quite far if you add a bottle every other tank or so and it doesn’t take up much room. But I wouldn’t try and drive around some parts of the world in anything other than a diesel anyway.

YMMV

Ian

My 2008 lr3 adaptive sensors are cleared after a battery disconnect. I know this because my obd2 scan tool has an obd2 test readiness feature that ensures all the values are populated so you will pass that check in a CA smog test. When I disconnect the battery and run the readiness it failed and shows n/a for all the values. After 100 miles or so and I rerun the test passes and all the values are present. I will point out when I disconnect the battery I touch the pos and neg cables together for a hard rest. I can also clear the sensors with my obd2 tool...verified with same method stated above.
 

ipgregory

Adventurer
Not sure your test is really proving what you think it is. I don't know the ECU set up of the more recent trucks so I cannot say for sure but from what you have said you only know it is clearing a flash memory containing test report values used for emissions testing. That does not mean that it is clearing the long term adaptive values that are used to modify ECU operation. Maybe it is, maybe it isn't. My point is that your original statement came across as a very blanket one that applied to all modern trucks and that is certainly not the case.

The OP posted about a 2012 truck of course but this thread has moved a little to discussing running lower grade gas in general. Others reading the thread who might be considering the question would be working from bad info if the believed they could clear their trucks with a simple battery disconnect or that their trucks will run just as well and there are are no downsides to using lower octane fuel.
 
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Daryl

Adventurer
Also remember these are European vehicles designed (initially at least) to run on Euro Fuel with much higher octane ratings even than US premium.

I believe you are confusing rating systems. Europe is RON, the US is AKI ((R+M)/2). 95 RON is only 90 AKI.
 

ipgregory

Adventurer
I probably am, but 95 RON is regular gas in Europe (or was 10yrs ago when I left). What is 98 RON (Super Unleaded in Euro Terms) in US terms?
 

KyleT

Explorer
YES, run high grade if possible. the direct injection system does not like low grade. and even still, buy from reputable gas stations. QT and racetrack are NOT the place to buy from.

Change the oil at 7500. NOT 15k.

not all adaptions are cleared by simply disconnecting the battery on any newer land rover. IDS/SDD is needed to fully reset them. yes it will adapt to low grade/quality fuel, but the effects include it running rough and idle fluctuations. as well as the other things mentioned above (ie injectors clogging ect...)

the LR4 is MUCH improved over LR3. and absolutely buy the 100K warranty.
 

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