Which is better, Part time or Full time?

[AdventurerSport]

Yup, what Norm said...:) Fulltime 4wd RULES! If you need a 4x4, why would you NOT want it to work fulltime?? If you don't need fulltime 4wd, you probably don't NEED 4wd, you just think that you want it...:P

I'll put any of my fulltime 4wd Power Wagons against any parttime 4x4 comparable truck for a fuel mileage race...:)

JS

[Gordon Maney]

I didn't put it in 4WD that day. If it was in 4WD the front tires never spun, if fact if you remember, I found one hub turned "in" and one hub disengaged.
I suppose that the CAD was only used on 100 and 200 (150-250) trucks, with the Dana 44, but I have a 85 W350 front axle in my W200 and it was originally a CAD axle (but it has Dana 44 tubes so that answers that question).
Keeping the hubs turned all the time defeats the purpose of the hubs as far as wear and tear and fuel economy, so I suppose you'd be better off with a Fulltime system....= )

I suppose if a person truly did leave hubs locked in all year long, they might be better off with fulltime. But, living in Iowa, which AdventurerSport is familiar with as well, I only need four wheel drive occasionally in the winter. [....this entire discussion is academic with my 2001 truck, since it does not have lockouts....]

So, I might lock my hubs in on my W300 three or four times in the winter. If there were some weeks where I thought the need could be more consistent, I might leave my hubs locked in. But, for likely more than eleven months out of the year, my hubs were free and everybody was resting, and that is good.

In the farm application, where the truck is worked a lot and on bad terrain in any season, then full time makes great sense.

As far as a comparison, physics tell us that if you had two trucks that were identical in every regard, and only differed in that one had locking hubs and the other had a full time system that ran the front end all the time, the lockout truck would get better mileage. I admire the enthusiasm, but those are the facts. Frictional load is undeniable.

[MoparNorm]

......As far as a comparison, physics tell us that if you had two trucks that were identical in every regard, and only differed in that one had locking hubs and the other had a full time system that ran the front end all the time, the lockout truck would get better mileage. I admire the enthusiasm, but those are the facts. Frictional load is undeniable.

I've often thought about that, not only because I prefer full time in some vehicles (1 Jeep is Part Time, 2 Jeeps are Full Time and the Dodge is Part Time) but because the fuel economy standards are supposedly such a big deal for Detroit to achieve. It seems as if fuel economy was really such an important aspect, they would go back to Part Time transfer cases.
Seems that many folks can't or won't shift a lever, Jeep is considering going to electric switches and eliminating the transfer case lever. I think they are the last holdout, and I'm not liking the absence of a lever, it's just one more thing makes us a little more disconnected from the vehicle.

[MoparNorm]

.....As far as a comparison, physics tell us that if you had two trucks that were identical in every regard, and only differed in that one had locking hubs and the other had a full time system that ran the front end all the time, the lockout truck would get better mileage. I admire the enthusiasm, but those are the facts. Frictional load is undeniable.

Another thing that may not be obvious to all reading this post is the way a NP424 transfer case operates, which is this:
It's in 2WD until you place it into Full Time, so the front is not being driven all the time, until you place it in that mode.
The options, with that case are;
2WD High Range
4WD Full Time High Range
4WD Part Time High Range
4WD Part Time Low Range

[AdventurerSport]

Frictional Load is undeniable. Ok, I won't argue with that...:)

Frictional Load vs. Real World Fuel Mileage, and the actual difference in mileage between 2 trucks, fulltime vs. parttime, is a very different arguement. Real world math tells you that it equates to less than 1 mpg, so it's really a non-arguement. Especially considering all the stuff that the average car guy adds to his ride that hurts mileage (bigger tires, deeper gears, steps, rollbars, pushbars, fog lights, all add weight and hurt MPGs), there is no intelligent arguement to support parttime 4wd simply for fuel mileage...

And, as I always tell folks...if you want GOOD fuel mileage, why are you driving a Power Wagon? :P I have a Plymouth Acclaim for fuel mileage, not my Power Wagon (even though I drive the PW every day). Lots of good, used, cheap Dodge Omnis/Plymouth Horizons out there that get great mpgs, why not drive one of them, and save your Power Wagon for truck stuff? :P

JS

[MoparNorm]

The Liberty with Full Time, big tires and lift gets 25-26 mpg on the highway, about 17 mpg in town.
The Power Wagon with Part Time, big tires and lift gets 15-16 mpg on a very good day.........= )

[Gordon Maney]

Another thing that may not be obvious to all reading this post is the way a NP424 transfer case operates, which is this:
It's in 2WD until you place it into Full Time, so the front is not being driven all the time, until you place it in that mode.
The options, with that case are;
2WD High Range
4WD Full Time High Range
4WD Part Time High Range
4WD Part Time Low Range

But the front is turning, right? ....axle shafts and differential?

I have to admit that I did not know that you had a two wheel drive possibility. I have been thinking about the early ones that were literally full time, and all you got to choose was whether it was in Loc or not. Am I remembering that right?

[Gordon Maney]

The Liberty with Full Time, big tires and lift gets 25-26 mpg on the highway, about 17 mpg in town.
The Power Wagon with Part Time, big tires and lift gets 15-16 mpg on a very good day.........= )

That is pretty good. What did it get before the big tires?

[Gordon Maney]

Frictional Load is undeniable. Ok, I won't argue with that...:)

Frictional Load vs. Real World Fuel Mileage, and the actual difference in mileage between 2 trucks, fulltime vs. parttime, is a very different arguement. Real world math tells you that it equates to less than 1 mpg, so it's really a non-arguement. Especially considering all the stuff that the average car guy adds to his ride that hurts mileage (bigger tires, deeper gears, steps, rollbars, pushbars, fog lights, all add weight and hurt MPGs), there is no intelligent arguement to support parttime 4wd simply for fuel mileage...

And, as I always tell folks...if you want GOOD fuel mileage, why are you driving a Power Wagon? :P I have a Plymouth Acclaim for fuel mileage, not my Power Wagon (even though I drive the PW every day). Lots of good, used, cheap Dodge Omnis/Plymouth Horizons out there that get great mpgs, why not drive one of them, and save your Power Wagon for truck stuff? :P

JS

Have you ever considered writing an article for the magazine, describing the virtues of the fulltime trucks? :-)

[AdventurerSport]

Wouldn't an article from my personal point of view about Fulltime 4wd be much to biased to be published in a magazine? :)

Jeeps with "Selec-Trac" offer 2wd mode or Fulltime 4wd mode
Jeeps with "Command-Trac" offer only parttime 4wd
Jeeps with "Quadra-Trac" (varies, QT II, III, IV), offer various forms of Fulltime 4wd, with locking front and rear differentials in some models, but no 2wd mode.

JS

[Gordon Maney]

Wouldn't an article from my personal point of view about Fulltime 4wd be much to biased to be published in a magazine? :)

Jeeps with "Selec-Trac" offer 2wd mode or Fulltime 4wd mode
Jeeps with "Command-Trac" offer only parttime 4wd
Jeeps with "Quadra-Trac" (varies, QT II, III, IV), offer various forms of Fulltime 4wd, with locking front and rear differentials in some models, but no 2wd mode.

JS

I am pretty sure that you are not serious, but just in case you are serious, no.... bias is not bad. I would expect you to have enthusiasm for fulltime, and also the later trucks. That is another slant on you doing an article. I just hate to wait until you are back in the combine....

[MoparNorm]

But the front is turning, right? ....axle shafts and differential?

I have to admit that I did not know that you had a two wheel drive possibility. I have been thinking about the early ones that were literally full time, and all you got to choose was whether it was in Loc or not. Am I remembering that right?

Yes LOC or Open, you remember that correctly.
With the NP242 (Select Trac) the front axles turn, but they are "dry" axles, really just CV units without axle housings. So I don't know how much drag there is, but there is some minute amount.

[MoparNorm]

That is pretty good. What did it get before the big tires?

About the same mileage, the larger tires are not that much larger 235/16 vs 245/16. It's hard to get real big tires without cutting up the fender lips. For what MoparTina uses it for, it's fine!


Some people however DO get a tad more serious with their Liberty's

[waynebo]

part time by a mile,,better gas mileage and less wear on t-case and front axle and front drive shaft,,tires too..also no annoying steering wheel kick back when turning,,and fun to shoot rooster tail on old dirt roads,,can't do that with full time..if the weather is bad lock in the hubs and use 4x4 as needed,,,who want 6-9 mpg with fulltime,,thats what i get with my m880,,sucks,,,wayne p.s= going to make it part time

I agree 100 %

[AdventurerSport]

I agree 100 %

You agree with What? Yourself? Do you realize that you're agreeing with your own post, or are you trying to be funny? :P

JS