Which is better, Part time or Full time?

[Gordon Maney]

I must admit, I would not have predicted the trend indicated by the poll.

[Russ Erickson]

NP-203 transfer case

Just a little side note here, I bought an NP-203 full time transfer case at the local salvage yard (junk yard to us older folks) about a month ago for $20.00. It was in a pile of scrap that they were about to scoop up with a front end loader and take to a recycler. I don't know if it was a Dodge or Chev unit. I sold it to a good friend who makes transfer case doublers with NP-205 transfer cases. The old NP-203s are still very cheap if you need to find one.

[AdventurerSport]

I get good deals at the salvage yards, usually, but $20 is super cheap! :) $150-$200 for a NP203 around here, if you can find one in a junkyard, trucks around here have to have been hit hard to end up in yard.

JS

[hpproron]

Great thread going here!!!`~~~

OK, this is a GREAT thread!!! I personally have voted for Part-Time because I am of the school that you 'pre-lock' your hubs when you think you will need it, and then PULL THE T-CASE KNOB when you KNOW you need it! :)

Here's my note of interest, however.

Since I have had my W300, it has NEVER had the front driveshaft installed. The previous owner had if off, and I never took the time (or money, for new u-joints) to put it on. Now, if you have read any of my posts from before, you'll know that my truck is better built and used at the local drag strip. However, I am VERY curious to know just what it will feel like if that front 'full-time, automatic' driveline is engaged. The previous owner had stated something about "The noisy front end when the driveshaft was on".....??? I don't really know what he was talking about.

I have owned and loved two manual locking 4X4's (a 79 bronco and a 96 f-150) as well as owning and appreciating an automatic unit in a 95 toyota.
My Bronco was the best with it's Dana 44 front axle and NP205 transfer. I had warn hubs on that.
Now, with my Dodge having Dana 60front/Dana70 rear, AND an NP205, I can only imagine the 4 wheel drive potential. I DO believe that the rear-end in my W300 has been modified to a Detroit locker, but I have not pulled the cover plate to confirm.

I'm starting to ramble here.....great post anyways!

Cheers fellas!!!!

Ron in NB

[JimmieD]

Lotta truck there, Ron! As for the noisy front end there's a couple of possibilities. With the shaft removed there's no torque transfer between t-case and front axle, so the torque thrust on transfer output shaft doesn't ocur. But 205's are real stout and that's very rarely a problem area. Next of course, the driveshaft u-joints. But those are spicer 1350 and they too are stout, rarely causing problems and very easy to fix. So easy [and cheap] that it seems the former owner would toss in new ones if he already had the shaft out!??

I'd bet money, over a dollar, that the noise emanates from the actual axle u-joints in the front end. They rate a PIA factor of about 5 or 6, so they're potentially trying but not all that hard to change. Real similar to a standard u-joint job except for removing the axles, and that's not really that hard at all, mainly it's just time consuming. Thing is though, once your in there it's a real good time to stick in new brake pads, lube bearings, check brake flex lines, check seals, yadda yadda yadda.

Both type of axle u-joint works fine, if you buy Spicer branded, either lubed for life or the ones with a grease fitting. If you decide to do it I very strongly recommend you spend the extra couple of bucks to get Spicer, THERE IS a difference!

The 'what it will feel like' part is hard to describe. Only way I can say it is the truck suddenly feels like it's glued to the pavement. It's almost like the difference in driving a manual trans vehicle compared to an auto trans, you know, the way a manual just feels so much more 'attached' to the engine, axles and road? Try it, youll LOVE IT! :~ )

[MoparNorm]

My 2 cents:....
The previous owner tricked out the rear gear with a Detroit, but he installed the wrong gear ratio.............

[hpproron]

JimmieD!
Thanks for the input!

The rear driveshaft was rebuilt after I blew the flange yoke to pieces on a street launch one day. Basically, a whole new rear driveline is in there now! All Spicer, of course!

The front driveshaft that the owner gave me did not even have any u-joints in it, as well as the straps were missing. So, needless to say, when I get the front shaft shipped down here to Texas (maybe next year), I will have the whole thing rebuilt and balanced before re-installing it.

I DO feel quite a vibration at higher drive speeds, and I do suspect that is from end-play/movement on the free end of my front X-sfer yoke. I mean hey, there is no 'backpressure' there...it's just spinning in the air! ( I even notice this vibration when the transfer is in the 2HI position!!!)

Anyhow, the most important thing for me now is to get the new camshaft and components in so I can get the ole beast up and running again. This too will be at least a couple more months before I can afford the parts. All this high performance stuff is costing me and arm, a leg, a set of teeth, some hair, my dog and a couple children!!!! LOL!

Thanks again for your post!

R

[hpproron]

Yeah Norm!

The rear end, as HE quoted to me years ago, "Is a 5.74-to-1 ratio."

I've never done a tooth count nor have I done a 'spin-test' to confirm this, but I DO know that it's way up there somewhere!

[AdventurerSport]

better check the front and rear ratios before installing the front driveshaft...could be a major problem...good luck!

Fulltime 4wd RULES! :)

JS

[wsm41bn]

I have kinda liked the fulltime 4wd on my truck, ot seems really good around here working in the fields and going down logging roads, But i was wondering how it is on the snow and ice because im gonna be in alberta canada, this fall, I have a limited slip rear end in the truck also

[Clint Dixon]

I am not sure this poll provides enough choices or proper choices if you will, to allow me to cast a vote.

I think I am looking at the whole 4-wheel drive concept a little differently than most of the people, who have posted here, with the notable exception of Paul Cook. I guess I am going back to the grass roots thinking on the subject.

To me, my WDX with the NP 200 transfer case represents the best application of a system having four driving wheels. The WDX was basically designed to be an "all the time" 4-wheel drive vehicle created to carry heavy loads where there were no roads. If needed, the driver could reach down to a lever and disengage the transfer case gears that were providing rotational force to the front axle. One reason to make this choice could have been when one maybe wanted to take an occasional drive on hard surfaced roads. Once back in the natural environment that the truck was designed for, the driver simply reached down and shifted the lever back again allowing the transfer case gears to engage. The driver made the choice. The truck did not. He never had to get out of the truck to do so. This, of course, meant that the idea of having front axle drive hubs that manually disengaged was truly a foreign concept.

My '98 Jeep Cherokee with "Command Trac" (I can't remember the actual transfer case number) is basically the same. The driver makes the choice to either cause the front wheels to be driven, or not to be driven. He never leaves the vehicle. No “lock out” hubs are required.

Now there are two problems with my observation though. First, both vehicles have their transfer case lever/s arranged in such a fashion to make it appear that having the transfer case gears to the front axle disengaged (2WD) is the natural state for the transfer case to be in. And second, I do have aftermarket drive hubs on the front axle of my WDX that allow the axle shafts to manually disengage from the hubs. The majority of the time I drive the WDX in an environment that it was not designed for – on paved roads. I have become soft. I enjoy lessoned drive train vibrations while traversing the paved roads.

[Steve G]

Hey Clint, my 99 Cherokee has a "select trac" transfer case. I have the choice of 2wd, full time 4wd, part time 4wd, and low 4wd. From my understanding on how this works is the part time selection is the same as the old trucks, both front and rear drive shafts are "locked" together and turn the same speed. Now the full time selection lets the transfer case slip for going around corners and is good for the wife to drive when the roads have patchy ice and snow or she isn't sure if it should be in 4wd. When the snow/mud gets deep the full time 4wd is worthless compared to the part time "locked" selection, and I have demonstrated that for her so she could remember. The manual says that you can run it in full time all the time on hard pavement or whatever. Part time is used only for maximum traction on non paved surfaces. So my vote goes with the part time.

[MoparNorm]

I am not sure this poll provides enough choices or proper choices if you will, to allow me to cast a vote.

I think I am looking at the whole 4-wheel drive concept a little differently than most of the people, who have posted here, with the notable exception of Paul Cook. I guess I am going back to the grass roots thinking on the subject.

Actually, that is how the Full Time/Part Time cases used to be labeled, until about 1982 or so when it became so confusing that Jeep (New Process) decided to confuse the issue even more. They decided that Part time meant, only part of the time and Full Time meant that it could be run all of the time in that mode, the mindset of pavement vs. off-road had sissified by then and the die was cast.
I like the ability to run in 2WD Low Range at times as that allows a certain flexibility in high traction situations, without having to turn the hubs.

[MoparNorm]

Hey Clint, my 99 Cherokee has a "select trac" transfer case. I have the choice of 2wd, full time 4wd, part time 4wd, and low 4wd. From my understanding on how this works is the part time selection is the same as the old trucks, both front and rear drive shafts are "locked" together and turn the same speed. Now the full time selection lets the transfer case slip for going around corners and is good for the wife to drive when the roads have patchy ice and snow or she isn't sure if it should be in 4wd. When the snow/mud gets deep the full time 4wd is worthless compared to the part time "locked" selection, and I have demonstrated that for her so she could remember. The manual says that you can run it in full time all the time on hard pavement or whatever. Part time is used only for maximum traction on non paved surfaces. So my vote goes with the part time.

You're missing a huge benefit of the Select Trac (NP242). The Part Time mode is a 50/50 split between front and rear (it may actually be 49/51) to the ONE drive wheel on each axle (unless you have lockers).
Full Time is a "slip sensing mode" which sends traction to the axle, front or rear, which needs it. It is a perfect system for wet, slick, snow and or icy roads where the Part Time mode might break an axle component.
When you are in an off-road situation you can simply shift into Part Time for the old style 50/50 split.
Anytime you get tired of that NP242 you can ship it to me....= )
The only internal difference between the "Command Trac" Part Time case (NP241) and the "Select Trac" (NP242) is the extra cluster which makes the NP242 slightly weaker because of the additional moving parts. It's a great system for folks in the real world who spend 80% of their time on pavement, it also saves fuel when off-road.

However, I would think that the main point of this thread is to compare preferences between the group of NP200, NP201 and NP 205 vs. the NP 203, 208 and later cases found in the age of CAD and electric switches. I like the fact that Jeep has forsaken those labor saving gimmicks and gives us a real lever attached to real gears.

[Steve G]

When the thread said which one is better, I was mostly thinking of off road situations (or bad on road situations). That transfer case in my jeep is really nice for the choices, but in the off/bad road the part time wins. It probably makes a difference that I have a factory sure grip in the rear also. I have a 87 Ramcharger with the np208 that I ran like a part time because the vacuum pod was bad and parts missing (the axle slider coupling always engaged), so I put on lockouts and ran it that way. Usually a person knows when to have the lockouts engaged, I would leave mine engaged all winter so I could shift in 4wd when needed, and locked out in the summer.
A friend of mine has a 78 Plymouth Trail Duster with full time and the only advantage I see is being able to shift into 2wd Lo on the transfer case. He also had a Grand Cherokee that was full time all the time with no option for 2wd.
Also Norm, I don't think my wife is going to let go of the Cherokee anytime soon. I'll see if you're still interested in 20 years when it finally dies!