Mid-size vs Full-size truck setup

[tacollie]

You aren't supposed to drive in 4h on dry pavement with a traditional transfer. I don't do it. The majority of people I know do it and never have an issue. They complain about how bad their trucks handle in 4wd but never connect the did. I used to try to explain it to people but I stopped trying a long time ago.

 

[phsycle]

I think it depends on the 4WD system, no? My first-gen Sequoia had a separate center diff lock with 2WD, 4Hi, and 4Lo. I didn't make it a habit to use 4WD on totally dry roads, but never experienced any binding/etc. on the short stints where I did when cruising along mixed surfaces with drive pavement intermixed. Though I also never did any tight turns. With that diff locked? Absolutely not unless going straight or on really slippery surfaces. That may be the difference, too, where a "traditional" 4WD always uses a locking center diff?

Either way...if there were damage from someone binding up the drivetrain in a high-grip situation, it should be readily apparent!

Edit: And now realizing that traditional transfer cases don't actually utilize a center diff. Learned something new!

Just posting for posterity: First Gen Sequoia’s had a traditional part time transfer case. Second Gen had a center diff so could be driven in 4/AWD on dry pavement (until you lock the center diff).

The only time I had an issue was with a 3rd gen Runner. I accidentally ran 4wd on pavement and had the transfer case seal blow.

 

[K9LTW]

Just posting for posterity: First Gen Sequoia’s had a traditional part time transfer case. Second Gen had a center diff so could be driven in 4/AWD on dry pavement (until you lock the center diff).

The only time I had an issue was with a 3rd gen Runner. I accidentally ran 4wd on pavement and had the transfer case seal blow.

My ‘05 had an e-locker center diff, so 4Hi was technically 4A as it was an open diff when unlocked, no?


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[phsycle]

My ‘05 had an e-locker center diff, so 4Hi was technically 4A as it was an open diff when unlocked, no?


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Doh! My mistake. I believe you’re right. 1st Gen sequoias also had a center diff.

 

[jaywo]

What tacollie said. 85 octane at altitude is like 87 in the lowlands. In oversimplified terms, less oxygen = need for fuel that ignites easier. 93 octane here = 91 out there, typically. And it's running lockers that you don't want to do on dry pavement...4Hi is fine. Otherwise you couldn't have full-time 4WD vehicles.

The “85 octane at altitude is like 87 in lowlands” works for non turbo engines with carburators. This has been obsolete for decades with newer turbo engines. It’s well documented online. Also, Ford manuals specifies that even at high altitude 85 Octane should never be used and can void the warranty.
85 Octane for turbo engines is bad regardless of the altitude. Thankfully, the ECU can pull timing to make up for it and avoid knocking, but still not ideal.

Also, 4H is not fine on the road. The number of people on forums online saying “my truck has an issue, it’s hard to turn and it makes weird noise when I drive in 4WD on the road” is astonishing.
Your comment is precisely why I was concerned, the majority of people do not know how to treat their car properly . But as someone pointed out, the Truck is under warranty so I am not too concerned, and it’s only speculation on my end, maybe the previous owner did nothing wrong.

 

[phsycle]

The “85 octane at altitude is like 87 in lowlands” works for non turbo engines with carburators. This has been obsolete for decades with newer turbo engines. It’s well documented online..
85 Octane for turbo engines is bad regardless of the altitude. Thankfully, the ECU can pull timing to make up for it and avoid knocking, but still not ideal.

Also, 4H is not fine on the road. The number of people on forums online saying “my truck has an issue, it’s hard to turn and it makes weird noise when I drive in 4WD on the road” is astonishing.
Your comment is precisely why I was concerned, the majority of people do not know how to treat their car properly . But as someone pointed out, the Truck is under warranty so I am not too concerned, and it’s only speculation on my end, maybe the previous owner did nothing wrong.

Even for non-FI engines, owners manuals specifically state 87+ must be used.

 

[jaywo]

By the way, to everybody who said I should not consider mid size, and that I should buy a Super Duty, have a look at this thread, it’s interesting:

Camping In a GFC With Kids

With a couple additional adventurer partners, we are adapting to another type of adventure. This one involves more snack breaks, scenic potty stops, and quite a bit more gear! I wanted to share some things we have learned and open up a discussion with other Go Fast Families. A little bit of...

forum.gofastcampers.com

Multiple families of 4+ (my favorite is the family with 2 older kids + 1 huge dog) are camping in a ridiculously small GFC. The Family with 2 kids and the dog is doing so in a Tacoma, and they take long trips down to Baja. Incredible. 2 adults on top, 2 kids down below, and don’t ask me where they put the gear. The GFC is the last pop up I would buy, even with a family of 0.

 

[Tex68w]

Definitely go full-size, definitely consider a trailer in addition to. IMHO, the new Tundra is not the same Tundra we all know, it wouldn't even make it in my top three of full-size trucks if I were shopping at the moment. I'd also consider adding a trailer to your current 4-door Bronco setup, it would be the cheapest option with the least amount of additional work.

 

[K9LTW]

The “85 octane at altitude is like 87 in lowlands” works for non turbo engines with carburators. This has been obsolete for decades with newer turbo engines. It’s well documented online. Also, Ford manuals specifies that even at high altitude 85 Octane should never be used and can void the warranty.
85 Octane for turbo engines is bad regardless of the altitude. Thankfully, the ECU can pull timing to make up for it and avoid knocking, but still not ideal.

Also, 4H is not fine on the road. The number of people on forums online saying “my truck has an issue, it’s hard to turn and it makes weird noise when I drive in 4WD on the road” is astonishing.
Your comment is precisely why I was concerned, the majority of people do not know how to treat their car properly . But as someone pointed out, the Truck is under warranty so I am not too concerned, and it’s only speculation on my end, maybe the previous owner did nothing wrong.

We've already established the confusion I had re: 4HI...and that it's really 4A (which is also not proper AWD) despite having a transfer case in some vehicles with a separate center locker. My RAM has a traditional transfer case, and no it doesn't get run on dry pavement. Poor horse, it just wants to sleep .

As far as octane...agree to disagree. Air:fuel ratio is undeniably affected by air density from both altitude and ambient temperature (a whole 'nother thing that's not even worth calculating). That's why regular is 85 octane at higher elevations and 87 here at 600 feet. Mid-grade at altitude = regular here. And it can be rather hard to find 93 in the mountains, particularly away from cities...hence the proliferation of 91. Nothing about modern vehicles has altered the amount of oxygen needed to properly burn a given amount of fuel at a certain compression level, they've simply incorporated an increasingly advanced ability to advance and retard timing to adjust for variations in atmospheric pressures. Turbos, typically, run at higher compression, so they usually need higher octane, sure. But the newest turbo Subarus, for instance, are tuned for 87 while my '18 Forester XT recommends "premium" which, stated in the manual, is a minimum of 91...the stuff at altitude, which is 93 here as you can't even find 91 save for rare stations. Now would it run on 91 here? Most likely it would retard the injection timing enough to make it work, but I wouldn't run it.

My RAM calls for a minimum of 87. What no manufacturer will tell you is at what altitude that number is for...I'm sure because most folks wouldn't know what to do, and because of the vehicle's ability to adjust as necessary. I never advocated running less octane than the manual calls for, though my truck ran just fine when I couldn't find anything but 85 for a couple days above 8k feet...and it saved me some money. Science is science and being able to drop octane at altitude is also "well documented online." I agree that newer engines (being forced induction or NA has zero to do with it) have made it "obsolete" insofar as they have a far greater ability to fiddle with timing, however it's still a thing, and can save you quite a bit of money so long as you stay within the vehicle's tuning parameters.

 

[phsycle]

By the way, to everybody who said I should not consider mid size, and that I should buy a Super Duty, have a look at this thread, it’s interesting:

Camping In a GFC With Kids

With a couple additional adventurer partners, we are adapting to another type of adventure. This one involves more snack breaks, scenic potty stops, and quite a bit more gear! I wanted to share some things we have learned and open up a discussion with other Go Fast Families. A little bit of...

forum.gofastcampers.com

Multiple families of 4+ (my favorite is the family with 2 older kids + 1 huge dog) are camping in a ridiculously small GFC. The Family with 2 kids and the dog is doing so in a Tacoma, and they take long trips down to Baja. Incredible. 2 adults on top, 2 kids down below, and don’t ask me where they put the gear. The GFC is the last pop up I would buy, even with a family of 0.

I mean, it’s all relative to the options available. There was a time when a family of 6 took trips in a regular cab F100, 4 in the cab and 2 in the bed. I have family members with 2-3 kids taking long road trips in a compact car. Anything is “doable.”
How comfortable and safe you want to be, that’s the crux of the discussion.

For the record, for my family of 5, I’m not taking trips longer than an hour in a midsize. If that.

 

[K9LTW]

I mean, it’s all relative to the options available. There was a time when a family of 6 took trips in a regular cab F100, 4 in the cab and 2 in the bed. I have family members with 2-3 kids taking long road trips in a compact car. Anything is “doable.”
How comfortable and safe you want to be, that’s the crux of the discussion.

For the record, for my family of 5, I’m not taking trips longer than an hour in a midsize. If that.

And the chances of riding in the bed increased in relation to the number of times "Are we there yet?" came out of your mouth.

 

[phsycle]

And the chances of riding in the bed increased in relation to the number of times "Are we there yet?" came out of your mouth.

Might be why when I was a youth riding in the bed, the window to the cab was locked 🤣

 

[rruff]

Hmm... I learned something today! Apparently the reasoning for lower octane at high altitude came from a 1942 study, while a 1987 study (still far from recent!) concluded that the octane need for modern (1987) engines dropped by only ~0.2 points per 1,000 ft, so at 5,000 ft 85 octane is about like 86 octane at sea level.

Oddly, the great majority of internet sites show no references, but are parroting the conclusions of a 1942 study!... ie, "low octane at altitude is fine"

This doesn't mean that 85 octane will hurt your engine, but efficiency and power will be reduced due to timing retard. Turbo engines are more greatly effected as well.

I've pretty much always used 85 octane in my truck, and never heard a hint of knock, so if it's correcting it's very quick. I also get better MPG at altitude, but that's surely due to lower air resistance.

 

[phsycle]

Hmm... I learned something today! Apparently the reasoning for lower octane at high altitude came from a 1942 study, while a 1987 study (still far from recent!) concluded that the octane need for modern (1987) engines dropped by only ~0.2 points per 1,000 ft, so at 5,000 ft 85 octane is about like 86 octane at sea level.

Oddly, the great majority of internet sites show no references, but are parroting the conclusions of a 1942 study!... ie, "low octane at altitude is fine"

This doesn't mean that 85 octane will hurt your engine, but efficiency and power will be reduced due to timing retard. Turbo engines are more greatly effected as well.

I've pretty much always used 85 octane in my truck, and never heard a hint of knock, so if it's correcting it's very quick. I also get better MPG at altitude, but that's surely due to lower air resistance.

I’m unsure if 85 octane will hurt your engine, but every owners manual from late model vehicles do state using anything less than 87 could damage the engine and warranty will be void. Frustrating for us in high elevation states.

 

[jaywo]

Hmm... I learned something today! Apparently the reasoning for lower octane at high altitude came from a 1942 study, while a 1987 study (still far from recent!) concluded that the octane need for modern (1987) engines dropped by only ~0.2 points per 1,000 ft, so at 5,000 ft 85 octane is about like 86 octane at sea level.

Oddly, the great majority of internet sites show no references, but are parroting the conclusions of a 1942 study!... ie, "low octane at altitude is fine"

This doesn't mean that 85 octane will hurt your engine, but efficiency and power will be reduced due to timing retard. Turbo engines are more greatly effected as well.

I've pretty much always used 85 octane in my truck, and never heard a hint of knock, so if it's correcting it's very quick. I also get better MPG at altitude, but that's surely due to lower air resistance.

It’s funny because I saw this video a while ago and was going to post it here after I saw your previous message before that one.

Also, as Phsycle just posted, contrary to what you said in the previous message the manual specifically mentions High Altitude.

Anyway, I am not blaming you for not knowing. I am blaming governments and corporate for allowing sale of 85 Octane in 2024. I am also blaming corporate for advertising often a very low « regular » (85 octane) price, then when you put 87 it’s 25% more expensive and pretty much the same price as 91. Not all gas stations do this thankfully.

But again, more people than not thought all of that was okay, in fact I would say more people than not know even less, and it’s no wonder many cars have reliability issues past 100K miles.

Of course, with all that said, the Tremor is already at the dealership because the transmission or engine is making a high pitch high frequency whine noise at low speed.
I am punshing myself in the face for buying used. Whoever is gonna buy my Bronco is the luckiest person ever. Impeccable engine break in, premium gas only, 5 tire rotation and oil change every 5K miles, touchless car wash only, screen protector from day 1, hell I even refused the « free gas tank » from the dealer when I picked it to make sure they didn’t put bad fuel. Never ate in the car. Makes me cringe when I see people have their skis sit on the side of their vehicle at the ski resort parking lot. I would never do that and risk a scratch.
Yes I treated the Bronco like I would keep it a lifetime, yes I am crazy.

Appart from that it’s incredible how quiet and spacious and comfortable the F150 is. It feels like way too much space right now, but hopefully when baby comes it feels the right choice.