Part-Time 4wd kit good or bad idea? (1 Viewer)

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So I'm planning on taking our 100 on a few thousand mile road trip this June to Colorado for a wedding and then on some sort of adventure across the States. IMO, the 100 is one of the sweetest and most plush rides to tour around in, but it has crappy fuel economy; something which I've been trying to figure out ways to increase as I'm thinking gas is gonna skyrocket this summer.

I have been trying to decide what my first real mod is going to be and decided that savage trail armor, lockers, and a lift might have to wait until I've got more $ burning a hole in my pocket (or someone decides to hit me and their insurance buys it for me :D). I've been strongly leaning towards doing the part-time 4wd conversion because to me it sounds like the only modification I could do that could potentially pay for itself in a reasonable amount of time. Hypothetically, it could keep the wear down on front driveline components as well as give me a slight increase of MPGs. I haven't found much info at all regarding the part-time for a 100, but for an 80, it seems that I'm gonna lose my ABS unless I have my front hubs locked - which would kinda defeat the purpose of being able to unlock everything. This is something that I'm still unclear on.

I'm also justifying the part-time because I don't really "need" the full-time/awd because I don't live in an area that sees "real weather" like snow/ice or wet/slick roads unless I'm going up to Tahoe in the winter. If road conditions are to the point where chains are required, I'd most likely be putting it in 50/50 4wd anyways - same thing offroad.

So I'm wondering if anyone has any comments or suggestions to talk me into/out of the part-time idea.

Off topic, but wouldn't 285-75-16 (some kinda aggressive AT) tires give me better gas mileage on the hwy due to lower RPMs and increased tire circumference? I'm aware that it would give me worse MPG for city driving as well as throw off my odo/speedo. I was just wondering about the tires because eventually I plan on going the off-road route with this rig and will be putting bigger meats on, but don't know which would be better to do now since they will end up being around the same cost (good tires vs part-time).
 
The only scenario I can see for doing this mod is to eliminate vibes if the truck is lifted too high. Since we're limited on the 100 to 2.75" lift we don't get vibes.

*CV's last 40K minimum even if you wheel like me. Typical is 50-100K. Boots still wear/dry out.
*Your savings on the front-end parts not turning is minimal.
*Selectable 4WD vehicles running in 2WD mode vs Full-time is under 1 MPG difference because the excess weight is still there.

So what do you really gain? Basically nothing.

Then you have the flat-out negatives:

*Changing out proven and ultra-reliable parts for aftermarket ones
*Full time 4WD will not be engaged if needed in an emergency situation
*You lose the potentially life-saving VSC feature in your model
*TRAC will not work either unless you first engage

I see it as a total waste of money for 99% of the owners and one that makes your ride less safe. Your payback on investment would take a long time. I see no real good (though I'm sure on a forum there will be 1 or 2 or 3 people who have done it and will say it's gods gift to their LC and everyone should do it). :rolleyes:

KEEP YOUR MONEY!
 
Ok, now I've changed my mind. Part time on the 100 has too many cons to be worth it - with the most important one being the loss of safety features. I got word back from Slee and I guess the 100s don't really wear on the front components that much as compared to the 80s solid axle does. I'd definitely be better off putting my money towards something else like sliders and some tires. Gonna be road tripping, so I already had planned on building up a set of drawers, so maybe a fridge would be a good thing to spend my rebate on.
 
So what do you really gain? Basically nothing.

Then you have the flat-out negatives:

*Changing out proven and ultra-reliable parts for aftermarket ones
*Full time 4WD will not be engaged if needed in an emergency situation
*You lose the potentially life-saving VSC feature in your model
*TRAC will not work either unless you first engage

I see it as a total waste of money for 99% of the owners and one that makes your ride less safe. Your payback on investment would take a long time. I see no real good (though I'm sure on a forum there will be 1 or 2 or 3 people who have done it and will say it's gods gift to their LC and everyone should do it). :rolleyes:

KEEP YOUR MONEY!


Wow, I actually agree with John on this one! :grinpimp:

Also, the bigger tires thing will actually cost you fuel economy in most situations, despite the (marginally) lower RPMs. Larger tires = more weight and mass and therefore inertia to overcome, which means fuel is wasted by the engine to power up. Also, more surface contact area = more friction that must be overcome by more engine power. Finally, you're speedometer will now be out of whack! There are legitimate reasons to up-size tires (after all, this is an OFF-road forum!) but fuel economy is not one of them.
 
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I evaluated the same mod and decided against it for all of the reasons John mentioned. If, and only if I was going to put a ton of highway miles on it would I have given it a second thought, but at $1k - $1.5k, you'd need to drive a lot of miles to break even, and then you'd have to deal with the downside of having that system anyway.

Got a dual battery, fridge etc... instead.
 
I did mine because I like the way it drives better with the front disengaged. I have never been a fan of AWD anyway and the kit saves wear and tear on lifted trucks and my big reason is that will flat tow my 100 behind a motorhome. I guess I am again the in the 1% group, which is OK with me.
 
Different strokes for different folks, i really like the way awd handles. Must be all those years of dreaming about World Rally!
 
so would the part-time be the solution to using the stock t-case in the event of a SAS? just curious.
 
I did mine because I like the way it drives better with the front disengaged. I have never been a fan of AWD anyway and the kit saves wear and tear on lifted trucks and my big reason is that will flat tow my 100 behind a motorhome. I guess I am again the in the 1% group, which is OK with me.

Kind of topic, but when flat towing behind a motorhome can't you put the transfer case in "Neutral" and be fine?
thanks for the input
jg
 
Kind of topic, but when flat towing behind a motorhome can't you put the transfer case in "Neutral" and be fine?
thanks for the input
jg

I would think without the part time kit your cv axles would still spin. Causing wear.

Yes, you can flat tow with the t-case in Nuetral.
 
Kind of topic, but when flat towing behind a motorhome can't you put the transfer case in "Neutral" and be fine?
thanks for the input
jg
When the T-case is in neutral and the wheels spinning, I think there will be a lubrication/heat problem in the T-case.
 
We looked into this and even took a tcase apart to see where/how it gets its oiling. It should be Ok to flat tow with 0 modifications even though the pump inside is not turning.

Thanks for the info!!!!
 
mpg question...

I'm running 265/70-17's on my T100 (stock fjc rims/tires) putting my speedometer and odometer off by ~10%. Of course the weight, width, and air pressure of the tires will affect performance, but by using the right mileage you may see a mpg or two that'd been hidding...

Make sure to correct your odo/trip before you divide by gallons of gas... my trip reads 340 miles from last fill up, in goes 19 gal for 17.9mpg. Using 340*1.1 i get 374 miles from last fill up, in goes 19 gal for 19.6mpg
 

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