When/How to use 4x4?

usually 4WD (even FT 4WD) are not the same as awd systems. awd systems do NOT have a 4LO. a good example is the 4runner. that is a FT 4WD system (in the limited models) since it has a 4LO.

that's why you never see Subaru calling symmetrical awd 4WD or audi haldex/Quattro systems 4WD since they don't have a 4LO gearing.

there has only been one awd system that had a 4LO in a car if I remember correctly but that was decades ago.

edit : also to add, not all awd systems have a center diff or a 3rd diff. I think only the wrx sti have a 3rd diff. the legacy only has a center diff that you can lock.

most awd systems don't even have a center diff (they use a computer to simulate a center diff by applying braking to the spinning wheel)

 

You can used 4w hi as long as you are in an environment that allows the wheels to slip a little, like snow, ice, dirt road, etc. I think you can use it in the rain, but I don't just to be safe. That's the simple answer. Again, all this is in the owners manual I believe. I don't see a situation that you would need to use 4wd faster than 60 mph, and 4w hi is fine at that speed. I live in Texas and we don't get snow, we get ice, so maybe you northern types drive that fast on snow, I don't know.

 

I had a full time 4WD, with low range. It was a Jeep with Quadra-Trac, back in the 70s.

The term AWD is just a coined term for most street and sport cars with full time four wheel drive. After all, all wheels are four. They each have special features and some might have low range, but those are usually the off road SUVs.

A third differential is primary to full time 4WD or AWD, so they can be operated on any surface, including dry pavement.

Subaru first had 4WD vehicles (70s and 80s)... which went from FWD (Front Wheel Drive) to 4WD by engaging the back wheels. They changed to AWD, and no longer offered low range, as they had begun to in the mid 80s.

AMC Eagle, Audi Quattro, and Toyota Tercel followed Suabru's lead in 4WD or AWD passenger cars.

Now most auto companies seem to have AWD or 4WD models.. it is just that good!

 

i heard to should atleast do about 10 miles a month on 4x4 to cycle the differential.. is that true?

 

that's what it says in the manual.

 

I think the manual says to use it to keep it lubed.

 

so what if you dont live in an area with snow.... i live in sunny california.. so can i just go straight for 10 miles on the fwy with 4x4 turned on for the next 10 miles?

 

Just drive down the highway 4x4 for 10 miles, its not as bad as everyone makes it out to be. That said, dont try and park or make u-turns, or tight turns while in 4wd. Just drive down the highway, the amount of turning you do on the highway is only a couple of degrees.

 

oh ok nice.. i drive local straight down a street to my work for lets say 12 miles so ill just turn it on 1 day out of the month i guess.

 

Lot's of good info there - thanks everyone. I'm new to 4x4 and trucks in general so i'm trying to make sense of all of it. It doesn't snow much here in Seattle, but when it does I want to be prepared and have assumed that I will only need 4H. I just get confused on all the trac, VSC and LSD stuff

 

Me too... and while I may not go 10 full miles each and every month... I turn the dial to H4 every week or two for a little bit, at least.

 

Just keep it simple and easy... sure! Dial it to H4 in snow. IF your tires spin trying to grab, then quickly push the VSC button (the one with a car and squiggly lines under). That will step up the traction control to a stronger level of limited slip, called TRAC OFF.

 

This is not true of stock 4x4 trucks. I have heard of off road racers doing it.

 

Very very few off road racers have four wheel drive... It is just too fragile (and heavy on the front) and not needed most of the time on where they race.

 

Kodiak Alaska gets a lot of black ice and slush on the highway to work. The road has bends and such. In town I use 2wd due to a lot of pavement turning. Once on the highway I use 4hi. When a get close to base, like driving into it, I switch back to 2wd. 4Lo for Off Road when I need it.

 

Savage lol

 

In the snow, but I think you all, already figured that out.

 

https://www.youtube.com/watch?v=4-Wy5ENm_lM

https://www.youtube.com/watch?v=ia463NahG5Q

https://youtu.be/Y7MF3q0v1hw

 

All part time 4WD trucks with 4WD engaged, the front wheels turn slightly faster than the rear wheels. If they didn't, you wouldn't be able to turn in 4WD. When turning, the turn radius of your front wheels is greater than your rear wheels, requiring your front wheels to turn faster than your rear wheels.
This is one of the reasons it's not recommended to have 4WD engaged on dry pavement. Going in a straight line on dry pavement with 4WD engaged, the front wheels turning faster than the rear wheels puts a lot of load on the drive train.

Different story for full time 4WD. They would have a differential between the front & rear wheels.