When to use my 4wd options

[HotxjGuy]

Hey guys I have been getting use to my jeep now and have been climbing and doing some trail driving and want to understand my jeeps 4wd system better


I have an 89 and I have
Part time
full time
and
Low

Both Part time and low say lock on them on my visor is this mean I have a locker?

I have noticed if I am trying to climb a hill that part time seems like its just two wheel drive
full time is great 4wd and does well but traction can be challenging
Low "lock" well is just so much easier I can basically just point the jeep and go no slipping or anything just seems to go right up its amazing haha


I am having a blast though!

Let me know when and how you would you use the three options

I think part time is for mainly two wheel drive stuff that is in the snow basically slippery roads but will engage 4wd when it feels its needed
full time is just that full time on any surface
and Low I am guessing locks it and allows for more advanced stuff like mud or hill climbs

[tinythexj]

One of the best ways to find what your jeep came with is to request a build sheet from jeep where they will list all the goodies it came with.

[4.3LXJ]

I use 4WD in any situation where traction is questionable. I use low range anytime my speed on trails and gravel roads are 25 mph or less. This is easier on the tranny because you can take advantage of torque converter lock up and reduce heat generated in the auto tranny

[Carves]

Hey guys I have been getting use to my jeep now and have been climbing and doing some trail driving and want to understand my jeeps 4wd system better


I have an 89 and I have
Part time
full time
and
Low

Both Part time and low say lock on them on my visor is this mean I have a locker?

I have noticed if I am trying to climb a hill that part time seems like its just two wheel drive
full time is great 4wd and does well but traction can be challenging
Low "lock" well is just so much easier I can basically just point the jeep and go no slipping or anything just seems to go right up its amazing haha


I am having a blast though!

Let me know when and how you would you use the three options

I think part time is for mainly two wheel drive stuff that is in the snow basically slippery roads but will engage 4wd when it feels its needed
full time is just that full time on any surface
and Low I am guessing locks it and allows for more advanced stuff like mud or hill climbs


Sounds like you have a 242 Transfer case.


OPERATING RANGES
NV242 operating ranges are,

2WD (2-wheel drive),
4x4 part-time,
4x4 full time, and
4 Lo.

The 2WD and 4x4 full time ranges can be used at any time and on any road surface.
The 4x4 part-time and 4 Lo ranges are for off road use only. The only time these ranges can be used on hard surface roads, is when the surface is covered with snow and ice.


Not wise to use 4x4 part-time and 4 Lo ranges on pavement ... or even hard packed, smooth service gravel roads imho.

[bcrosson92]

full time should be used on paved roads when its slick. ex snow part time and lo should be used offroad only unless u get stuck in a ditch in the snow or something. if you would like a more technical answer on how it works let us know we can give that too.

[HotxjGuy]

full time should be used on paved roads when its slick. ex snow part time and lo should be used offroad only unless u get stuck in a ditch in the snow or something. if you would like a more technical answer on how it works let us know we can give that too.
I was curious to know if I may have a locker? Both hi and low say lock on my visor

[prerunner1982]

That just means that the front and rear axles are "locked" together and will turn at the same rate.... use only offroad.

Also 4wd Full Time allows the front and rear axles to turn at different rates which is why you can use it on pavement, but it's still in 4wd all the time.

[bcrosson92]

not from the factory you wouldn't. the lock is referring to how the 4wd works. this will be a bit technical. full time works like this. its based on a torque ratio. when it reaches a high enough torque it will free spin the front output. low and full time are true "locked" meaning front and rear drive shafts will spin at the same rate no matter what. a locker makes wheel to wheel on the same axle spin at the same time. think 4wd lock means front to back and lockers lock left to right.

[HotxjGuy]

full time should be used on paved roads when its slick. ex snow part time and lo should be used offroad only unless u get stuck in a ditch in the snow or something. if you would like a more technical answer on how it works let us know we can give that too.
I was curious to know if I may have a locker? Both hi and low say lock on my visor?
Do you guys just leave it in full time most of the time and only switch when you need it?

[bcrosson92]

yes. switch when you need it. if your on dry paved roads or even just dirt ones you should use 2wd. now for snow i use full time on paved roads and dirt ones (unless its really deep like 6 inches or more then part time but go 25mph ) use part time anytime you are wheeling or its slick off road. i use lo ONLY when i get stuck or its realllly slippery. as for locker unless the preveous owner put a locker in you don't have one. you could put the axle on a jack and spin the wheels. if one spins but not the other no locker. the simple answer is no locker.

[prerunner1982]

I was curious to know if I may have a locker? Both hi and low say lock on my visor?



That just means that the front and rear axles are "locked" together and will turn at the same rate.... use only offroad.

[4.3LXJ]

I would suggest using 2WD on normal paved roads. It will save wear on the chain in the tcase. Continual use of Full Time 4WD will cause wear on the chain and eventually need to be replaced. Use the full time option in slick road conditions

[xj-jake]

My wife has the part time and full time in her WJ. Here's how I remember how it works. Part time on the shifter is for part time use NOT part time 4x4. Full time is where you could drive it on the pavement if you needed to. Obviously 4x4 on dry tar is not the best idea but that is how I remember it.

[bcrosson92]

My wife has the part time and full time in her WJ. Here's how I remember how it works. Part time on the shifter is for part time use NOT part time 4x4. Full time is where you could drive it on the pavement if you needed to. Obviously 4x4 on dry tar is not the best idea but that is how I remember it.

yes jake part time is 4wd till it gets up to speed then will let the front driveshaft free spin till its needed. the 242 is hard to wrap your head around.

[XJ Wheeler]

A little late to the game but i noticed another issue in your first post. You say that in part time you are only getting power to the rear wheels? This is a common problem with the renix era jeeps which have the front axle with a two piece inner shaft on the passenger side that has a vacuum operated shift fork that connects the shaft when in four wheel drive. The problem comes in when after 20 some odd years the vacuum hose cracks and generally has its problems leading to the vacuum actuator not working. Simple fix usually though, some new vacuum hose.

Sorry for leading us off topic, just didn't want to glaze over that.

As far as the use of the t-case. It may just be me but all that ^ sounds confusing.

2wd - Use on normal road conditions
Full time - Use on road whenever you feel you may lose traction and want a more confident feel but still want to go fast.

Part time - This is four wheel high range. Use it for general off roading where you need power to the front and rear.

Low - Four wheel drive Low range. This is your end all, busting up a rocky ledge, powering through the more extreme terrain, and helps to slow your downhill descent. Use it for the more demanding off road conditions basically.

Hope that clears things up.

Sent via messenger pigeon. I talk, he types.

[downsy]

yes jake part time is 4wd till it gets up to speed then will let the front driveshaft free spin till its needed. the 242 is hard to wrap your head around.

Not quite. It's torque-Biasing. It's splits 48 percent torque to the front nad 52 percent to the rear when in full time. It does that split all the time no matter how fast you are going. In part time operation the front and rear prop shafts are locked together and it's a 50/50 split.

https://www.novak-adapt.com/knowledge/np242.htm

To the OP. You might be interested to know a "Heavy Duty" version of this transfer-case is used in the Military HMMWV/Hummer H1. ;)

It's a good transfercase. I've been kicking around the idea of possibly swapping my NP231 out for a 242 to have the option of full time. But who knows I may never get around to it haha.