part time vs full time

bugsnbikes

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Im guessing most people with part ime and lifts have t gone with longer front control arms or pushed their stock ones forward in the frame side mounts to claw back lost wheelbase? Or fixed the rear uca's lost angle by raising the uca mount point to compensate for lift?

Given that some of the Jdm LC's had optional part time....i would imagine in a purely stock height and suspension setup- the Setup was fine for Toyota. Im wondering if all these little suspension shortcomings that people arent commonly addressing when adding lift (like panhard and uca mount raising-longer arms etc) are all magnifying the problems to the point that for some it feels very different/bad?
 
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In my case, my HDJ81 was on 4" lift, 3° caster 1/4 toe in each side, and radius arm shifted 3/4" forward at the frame, rear control arms extended and sleeved, rolling on 33" BFG A/Ts on road, 35" MTZs for playing in the dirt.
HZJ105, basically the same, but 2"lift, and slightly less caster at 2°
 
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Part time vs full-time 4wd for 80s is hotly debated on Aussie based 4wd forums.

Many do it purely because they think they will save fuel. I've never seen a documented assessment of fuel use before and after.
I used to track my fuel use, and anecdtotally I've seen no change running in AWD, or rear shaft out, or front shaft out for extended periods of time, including having the front shaft out, and drive plates removed at the hubs (smashed diff, and birf)

Others go part-time because it means they can drift their 80 in the dirt or do circle work (skids, doughnuts etc). I s*** you not.

For me, they drive ok in part time, but comparatively, not great, and far better in full-time AWD. Chalk and cheese.
 
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This mod has to be the greatest thing on a full time car if you are a wheeler. Limp out of trail if something goes wrong with the front axle, or even to save your bacon if you get on tippy situationand can’t go backwards.At the end of the day, lock your hubs and go home !
 
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This mod has to be the greatest thing on a full time car if you are a wheeler. Limp out of trail if something goes wrong with the front axle,
Meh. Kind of moot point, no advantage.

I've busted birfs, and pulled the broken birf on the trail, used the front locker to continue the trail and limp out in 3 wheel drive.

Once out of the bush, 10 minutes under the car to pull front shaft, and pull drive flanges at the hubs, lock the CDL and limp home.
I've also had to pull the rear shaft and limp home in front wheel drive due to a destroyed rear pinion bearing. Again 10minutes work.
 
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my 1997 came factory part time, so I have an H4 button on the dash that engages the front drive shaft. since it came with factory part time, I added free wheel hubs as there is no need to push the front shafts if they are not working (or so I think). It drives OK, when my wife drives it, I lock the hubs as she says it gives more steering feel. scary bits are being in a lifted (2.5") 2.5 tonne car with armor in twisty mountain rainy/snowy roads and having the tail slide out on every turn (35" BF AT2). option would be to engage H4 but I suspect that gives it 50/50 power distribution

Havent driven an AWD 80
 

Dissent

Questioning my life choices...
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Having my part time kit for about 2 years now, I think anyone would easily adapt to it. Buying a 20 year old truck, you really have no idea what it was supposed to feel like. Those who bought their trucks new probably do but over time, you get used to whatever it hands you as things wear out. I had discussions about handling perceptions with so many 80 owners who's answers ranged from "it's a 20 year old truck, it's going to be sloppy so deal with it" to "change all your bushings with OEM parts and then decide on how the truck is supposed to handle" and after replacing all the worn out suspension and driveline components I understand why the soccer mom I bought it from paid $68,000 for it. Nobody would have paid that much for the sloppy 20 year old mess I began with.

I had no choice in the part time conversion given the drive-line vibes I had after my TJM 50mm (2.5" lift, 4" overall including 20 year spring sag). I tried DC shafts and nothing short of a part time kit or a ball cut and turn would fix it. I'm not talented enough for a cut and turn so the part time kit fit the bill perfectly. In hindsight, I would not have installed the lift at all, just replaced the OEM springs and left it AWD, if I knew the issues that small lift was going to cause. 4+ years of wheeling on street tires and saggy LX springs taught me more about driving off-road than I could have imagined.

You live, you learn, you pay for crap you never saw coming, you live some more. Rinse and repeat. :)
 
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This mod has to be the greatest thing on a full time car if you are a wheeler. Limp out of trail if something goes wrong with the front axle, or even to save your bacon if you get on tippy situationand can’t go backwards.At the end of the day, lock your hubs and go home !
Or just pull the diff fuse and remove driveshaft.
 

smritte

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Many do it purely because they think they will save fuel. I've never seen a documented assessment of fuel use before and after.
I used to track my fuel use, and anecdtotally I've seen no change running in AWD, or rear shaft out, or front shaft out for extended periods of time, including having the front shaft out, and drive plates removed at the hubs (smashed diff, and birf)
Hmm lets see.
I drive to my sisters house 5-6 times a year. 3.5 (ish) hours, 242 miles (gps not odo.). Across the desert from Ontario, Ca to Summerland, Las Vegas (if someone wants to see the terrain). I would arrive at her house just above empty. Now I get there with almost a quarter tank left. About a needle thickness above empty to the same below quarter. Not very scientific but it was enough for me to notice. I have confirmed my fuel gauge accuracy only by adding fuel and comparing to what gauge reads. That has not changed since I've owned it.

This isn't one trip but several over the last year and a half (7-9 trips). Now I know someone is going to want an analysis on the fuel blend, the best you will get is I always run premium fuel and yes there is a difference in mileage with that (Ca and Vegas fuel stations).

Bottom line is, to me that difference is significant. I calculated it to "around" 2mpg.
Before Part-Time 11-12, after Part-Time 14-14.5.

Different fuel stations, different times of the year. You could say, I just drive different now and plot out the math where the loss from the front is not that significant. Don't drive any different and I don't have the log sheets from when I started tracking it. I tracked my fuel mileage obsessively from when I bought the cruiser, through all my mods and stopped before I did my part time kit. Mostly because of what I read and people telling me what horrible mileage Cruisers get. I didn't think Part-Time would make any difference based on what I read here. But it did.

Now I'm sure running with no front shaft and hub plates removed for several thousand miles would be a better comparison.

My vehicle spec's are, 1996, 2" lift, 35 cooper AT, stock gearing, fresh motor, open diffs, bumpers, winch, drawer system (haven't weighed it).


Disclaimer: Very few Prius were harmed during this testing.
 
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Sanchez

 
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I did a part time kit on mine few months back. My rig has a slee 4" lift, slee lower LCA's 315's, 488's and full armor. I tow a turtleback trailer with a family of 4 and so far I gained around 44 more miles of driving. Before, I was getting around 200 miles to a full tank, now around 244 miles or better highway (if I push it). I didn't do this mod for the gas savings, I did it so that it would help with towing and less wear and tear while driving around town. It definitely made an improvement while towing. I'm happy with the end results.
 

landtank

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I don't think comparing a AWD with no front drive shaft and a truck with part time is an apples to apples comparison. Even though the front axle in the AWD is disconnected from the t-case the front wheels are still linked to the diff and forced to rotate and adjust for differential speeds when turning.

I had to go part time because of a front auto locker and I don't really mind it. But I wouldn't say I prefer it either.

And provided the front axle is still located in the stock position on the arms it won't be rearward of the stock position until the truck is lifted over 4". In stock form the front axle is 2" above the horizontal plane set by the rear frame mount.
 

baldilocks

Battle Ground, WA
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Sensitivity levels are on the rise here. And, this thread is nothing compared to another one currently taking up space on the inter webs.
 
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I just part-timed my case and it has reduced driveline vibes significantly. I probably needed a DC front driveshaft, but I already had the part-time spool, so I just installed that for the cost of my labor.

I also prefer the way it handles. Steering is lighter.

Still getting some vibration at highway speeds, but that may be the caster out of spec, rear driveshaft, or rear panhard.

Part time and the DeltaV rear panhard correction bracket are probably the best mods I've done. I personally prefer the way it steers and picked up a bit of mileage on long trips. I am going to be biased as this was the first AWD I've owned. I don't have to contend with poor road conditions just horrible drivers. If I lived somewhere with ice and snow, it would be different.

Scott
Could you elaborate on the DVS panhard correction bracket? What do you like about it? How did it improve the truck? Tracks straighter and less "darting"?
 

smritte

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Could you elaborate on the DVS panhard correction bracket? What do you like about it? How did it improve the truck? Tracks straighter and less "darting"?
The rear sway was slightly noticeable in AWD over 70mph. When I did the part time conversion it was bad enough to scare me changing lanes at that speed. I have had a few Jeeps where the panhard wasn't lined up properly in the rear and this was way worse. Im thinking its the longer wheelbase. I'm sure the extra weight in the rear doesn't help either. Low speed the front seemed a bit light but that didn't bother me.

This Christmas was the first time I got to drive the vehicle on a long trip with the bracket installed. 250 miles each way up to 85 mph with no sway at all. Im running 3 degrees of caster and was thinking of bumping it some to stabilize it. No need now. In my opinion, if someones does a part time and freeway drives, they need to correct this. Any way possible. Unless you have access to some means of fabbing your own, the Delta bracket makes it easy.

Edit: I'm not running a cv front shaft. I did have a vibration at high speed but, thats gone with the part time.
 

LandCruiserPhil

Peter Pan Syndrome
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I have about 75K with PT on my current 80 I also run it on my LX470 but with more caster and love the way they both drive. Most people that have driven my 80 dont even notice. One of the biggest reason IMO is I run a solid 4° of caster and it provides tracking comfort at speed with good wheel feel. I have run/tried PT in other 80 and did not like it with the suspension set up as the 80 had to much lift when leaving from a dead stop. The front end was not stable and had a lot of up, down, and diving. The other part that I really like is zero vibs at any speed.:flipoff2:

Pull your drive plates and drop your front drive line and it will not take you long to figure out if PT its for you or not.
 

cme4lyt

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robbie A. mentioned a long while ago that he didnt like the handling characterisitics when he pulled his front driveshaft for long trips in 2wd. And im curious what people who have done the part time tcase kits think of the differences in handling? Does the front feel too light/ twitchy/ darty ? Or understeer/ oversteer etc?
I remember Robbie cautioning me before I went PT but I really didn’t think it was a big deal. Sure, it feels different but if you drive with that mindset, I don’t think it’s a concern.

I think he, and I at the time, were more worried about my wife, now ex, getting into the vehicle in wet conditions and things not going ‘per normal’ while doing a kids school run, a valid concern I think.

I actually like the ‘lightness’ or ‘crispness’ of the front wheels when in 2WD. It seems to turn easier and respond better with a lot less driver steering wheel input, which I like.
 

bugsnbikes

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Pull your drive plates and drop your front drive line and it will not take you long to figure out if PT its for you or not.
Its going to have to be for me.... as im doing Om606/h55f/ split case in the 80. So part time for sure.

the engine tranny tcase is 200lbs . less than the 1fz/auto that just came out. and it will be positioned slightly rearward to where the 1fz sat in relation to the front axle. rear end will be losing 300lbs of seats. so im hoping a 4200lb-4300lb 80 will be a tad more nimble handling wise.
a touch more castor correction and raising the panhards and UCA mounts and im hoping it wont handle too bad. Its currently got some 315/ 12.5. but im not at all opposed to trying 255/80 skinnies if the wider 35s track poorly or are sluggish on turn in. I guess i will just be doing lots of fiddling with castor/ toe/ mounts and overall suspension tuning with the Frankies springs which im hoping are a tad softer than the ones i have on Baconbits right now.
 
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