Do you live in an area that regularly experiences very cold, foggy weather with black ice conditions? Are you concerned about damaging your F150’s drivetrain if you engage 4A or 4H while driving on the highway? Are you concerned about damaging the F150’s transfer case if you drive in excess of 65mph while in 4A? If any of these are your concern then this article could shed some light on the subject.
Driving your F150 with 4A engaged on the highway is perfectly safe since the truck remains in 2H and automatically engages 4H when the truck detects loss of traction on any of the front wheels.
The F150 is a very popular truck and for good reason. Tough offroad credentials combined with its sophisticated drivetrain options make it a real beast in any driving conditions. Equipped with the 4A (4 All-Wheel Drive) functionality driving across a variety of road conditions is a pleasure. With that being said, is engaging 4A on the freeway void of any risks?
Let’s find out!
Table of Contents
F150 4A On Highway
The F150 is an engineering masterstroke and is designed with the ability to drive safely on the freeway. The A4 system was specifically designed to provide improved traction across a wide variety of driving conditions, including highways and freeways.
The 4A system will take all the guesswork out of the equation while you safely enjoy the ride.
So you can rest assured your F150 will be safe in 4An while driving in and around town when road conditions are slippery and wet or when it’s a mixture of low traction and high traction driving conditions. The 4A system will take all the guesswork out of the equation while you safely enjoy the ride.
4A – Road Conditions
Before engaging 4A it’s important to pay attention to the road surface conditions. Meaning, does it consists of a mixture of slippery and non-slippery conditions. Has it been snowing or raining recently leaving certain parts of the road with low traction while other sections are clean and clear? In these situations, the 4A system can provide added confidence and control, ensuring a safer driving experience.
Drivetrain and Transfer Case
What happens to the drivetrain and TC when you engage 4A? Well, unlike 4H, the 4A system actually runs mainly in 2H and only engages the front wheels when necessary. The advanced computer systems and wheel sensors take care of all the guesswork. While driving, the 4WD system makes thousands of calculations and reacts within split seconds once it senses the traction has been compromised. This gives you the benefit of returning the best fuel efficiency and safety combined. This is an advantage when driving in slippery road conditions like snow, sand, grass, wet roads, and steep inclines.
Fuel Consumption
However, it’s important to note that while the 4A system enhances traction, it does not necessarily mean that driving in 4A mode is always required or recommended on the freeway. In normal driving conditions, where the road is dry and well-maintained, utilizing the rear-wheel-drive (2WD) mode of the F-150 can be more fuel-efficient and sufficient for most situations.
WATCH – Ford F150 4×4 and Drive Modes Explained (VIDEO)
Driving In 4H On The Highway
This article discusses the effects of driving on a high traction surface like a dry pavement or a highway while a 4-wheel drive mode is engaged. We will be focusing mainly on part-time 4-wheel drive trucks since full-time 4-wheel drive vehicles can safely drive on low and high-traction surfaces such as concrete pavements and tarmac roads and highways without causing any drivetrain problems, due to its drivetrain system design.
Driving on dry pavement or highways with a part-time 4-wheel drive while 4H is engaged should be AVOIDED AT ALL COSTS.
Driving on dry pavement or highways with a part-time 4-wheel drive while 4H is engaged should be AVOIDED AT ALL COSTS. The reason for this rule is, that the drivetrain design of a part-time 4-wheel drive is not intended for high-traction surfaces such as dry pavements but rather for slippery, low-traction off-road terrain where traction is limited. Drivetrain binding will result if a part-time 4WD is driven for many miles on twisty highways.
Transmission windup occurs due to the front and rear driveshafts not being designed to rotate at dissimilar speeds while the vehicle is turning. Full-time 4WDs and AWDs that incorporate viscous couplings or multi-plate clutch systems are able to safely drive on dry pavements and highways.
So what happens to your drivetrain when you engage 4WD or 4H on dry pavement, or you forget to disengage 4H after you leave the dirt roads? How long will it take for binding to occur? This is a common occurrence and can easily happen to even the most experienced 4-wheel driver. The next part of this article will go into more detail about the cause and effects of Drivetrain binding as well as how the viscous coupling of a permanent 4-wheel drive functions. We will also discuss what happens when we reverse in 4WD mode on dry pavement.
User Experience & Feedback
User #1
So first off I’m new to 4×4’s, and didn’t know that I could be doing damage. I know better now but wanted to ask this. Had our first snow last weekend and I put it in 4h to drive to work. Got to the parking lot, and it was salted. Wet, but no snow or ice. I did a couple tight manoeuvres to park. It never hopped or skipped on me but I did hear some groaning coming from the front. Maybe that was just the tires roaring, but what do you guys think? It still shifts in and out of 4 normally. Should I get it looked at, at the dealership? No indications are on the dash, it seems fine, but from what I’ve been reading on here I messed up bad.
https://www.f150forum.com/f118/used-4h-dry-pavement-should-i-worry-369283/
User #2
Don’t worry about it. No you shouldn’t be using it on dry pavement, but it’s not like it’s so fragile that it breaks the first time you do it. If you do that a lot you could cause premature wear of some components.
https://www.f150forum.com/f118/used-4h-dry-pavement-should-i-worry-369283/
User #3
So, I live in the NW and we’ve been in the 30’s with fog causing a lot of black ice issues. I have a 2017 XLT Screw 4 x 4. I have 4H not AWD and I was wondering in it’s cool to drive in 4H doing highway speeds (65mph) on the highways. Going to work this morning changing lanes while passing it tried to break loose (in 2WD) a bit is why I’m asking. Thanks.
https://www.f150forum.com/f118/can-you-drive-freeway-4h-401997/
User #4
If you are losing traction in 2wd SLOW down. Yes you can run 4HI on the highway. Read your manual. I believe it suggests a top speed of 60mph. On ice it won’t help much at highway speed.
https://www.f150forum.com/f118/can-you-drive-freeway-4h-401997/
Resources
https://www.f150forum.com/f118/used-4h-dry-pavement-should-i-worry-369283/
Photo by Jason Pischke on Unsplash
Conclusion
In conclusion, the decision to drive in 4A mode on the freeway depends on the specific road conditions, weather, and personal preference. There’s no right and wrong application, however, It’s always advisable to consult the owner’s manual and adhere to the manufacturer’s recommendations regarding the appropriate use of the 4A system in your Ford F-150 to optimize performance and safety.