Guys, please excuse my horrible lack of knowledge when it comes to 4x4. This truck is my first.
I was doing some thinking about 4x4. I have read that some newer trucks have a 2-Lo setting on their transfer case. That is a good thing to have when pulling a boat up a steep and slippery ramp, or backing a trailer up a steep hill (i.e. my driveway!). Going up the ramp, you are basically going straight, so 4-lo would work correct?
Everything I am reading says 4 wheel drive engaged is ok if in a straight line on paved surface. You have problems when you start turning.
Now, when backing my boat up my driveway, I have to hit it on an angle, and turn, so 4-lo is out of the question. My truck has no 2-lo setting.
So, here comes my brilliant thought. Set it to 4-lo, and don't lock in the hubs. This will prevent the front diff from binding I think.
I know next to nothing about 4wd systems, so I figured I'd better ask before I go and do something stupid. Will I hurt my 4wd system by running in 4-lo with the hubs free? Kinda a red-neck 2-lo system I guess.
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Ryan
1988 F250 Supercab, 4x4, 7.3 IDI, C6 Auto, 147K miles
Banks Sidewinder non-wastegated Turbo, Stage 1 Injectors, and Pyro, Boost and Water guages.
i use 4 lo with the hubs unlocked all the time it works great for trailers and places when you need to go slow
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2001 dodge 2500 24 valve cummins diesel 6 speed strait piped and that is it SOLD my 1994 F250 4x4 IDI turbo 5 speed reg cab xlt 3 in strait piped200,xxx miles headache rack with tractor backup lights chrome brush guard 105 gal fueltank gooseneck hitch rebuilt inj pump turned up with pyro looking at boost gauge and injectors
1990 chevy ld2500 4 speed v6
2000 polaris xpedition 325 4x4 5 speed
Now that I have this truck, I plan to stop using my 5spd Dakota for putting my boat in the garage. I just hate the smell of the poor clutch when I get done with that task. With the lo setting on the xfer case, the F250 should do the job much easier.
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Ryan
1988 F250 Supercab, 4x4, 7.3 IDI, C6 Auto, 147K miles
Banks Sidewinder non-wastegated Turbo, Stage 1 Injectors, and Pyro, Boost and Water guages.
Since you have manual hubs has anyone tried leaving 1 front one unlocked, the only time windup comes into play is with both fronts locked in I believe..........am I out in left field again.... [img]/ubbthreads/images/graemlins/shrug.gif[/img]
__________________ http://photos.thedieselstop.com/show...0/ppuser/28329
93 F250 7.3 IDI S/C XLT 4X4 E40D 3.55LS, Captains chairs, Tutone Mocha, Leer 48" Hiboy cap, FR & RR hitches, full DeeZee running boards. Factory ordered/delivered Jan 93 has 160K+, it's basically a stock truck with all the Ford options, just no disc player.
Toys: 26'Jayco FK TT, 18'Sylvan Pro Fish.
I think some old jeeps were the only transfercases with 2 levers 1 for 2wd or 4wd and 1 for hi/lo range. I have a 2wd gas rig with the lame zf rev. and man, let's just say I always use 4 low when backing the trailer on my diesel. you won't hurt anything.
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I think some old jeeps were the only transfercases with 2 levers 1 for 2wd or 4wd and 1 for hi/lo range....
[/ QUOTE ]And I've heard they had an interlock to prevent shifting into low range w/o engaging the front end to supposedly prevent the possibility of sending excessive torque to the rear drivetrain.
I often use "2 low" on my '89 for loading my camper and backing trailers. It normally won't cause any problems.
If you're not careful, though.... [img]/ubbthreads/images/graemlins/tongue.gif[/img] I tried "2-low" on my old Bronco once while trying to climb a steep hill... I "Tootsie-Rolled" the rear drive shaft. [img]/ubbthreads/images/graemlins/tongue.gif[/img]
[/ QUOTE ]And I've heard they had an interlock to prevent shifting into low range w/o engaging the front end to supposedly prevent the possibility of sending excessive torque to the rear drivetrain.
I don't think so, If they did it would be simple to bypass. Because 2 of my friends operate their jeeps with 2 wheel low range. (sometimes it helps on the trails) The torque numbers weren't really high in the 1940 neither. The np205 can also be modified to operate this way for guys with lockers in the front this is a huge benefit, it saves unlocking the hubs sometimes when you have to turn sharp on muddy hills.
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Since you have manual hubs has anyone tried leaving 1 front one unlocked, the only time windup comes into play is with both fronts locked in I believe..........am I out in left field again.... [img]/ubbthreads/images/graemlins/shrug.gif[/img]
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hmmm....wouldn't the open-diff in the front cause the torque to be sent to the "free" side? I.e. what would be the 'spinning' wheel in a slip situation.
Analog; you quoted one source as saying to use 2-lo for "steep and slippery boat ramps". That's not quite right. You'd use it for -steep- ramps, but for -slippery- you'd want 4wd. Lo-range can actually exacerbate spin-out problems because there's just so much torque going to the wheels. It's hard to control it enough to prevent break-loose.
On a slippery ramp, I use 4-lo, but I don't worry about it even in turns, because it's.....slippery! [img]/ubbthreads/images/graemlins/biggrin.gif[/img]
A -little- bit of driveline 'windup' isn't a problem, as long as you are being careful with the go-pedal. The tires will generally slip/scuff to equalize on their own. However, if you're in a tight turn on bone-dry pavement, and whack the go-pedal hard in 1st-gear 4-lo,, then yeah, you'll probably break something expensive...
My other diesel is a...
Hydra 35-ton Excavator, 6V71T; Isuzu C201 genset;
'71 VanPelt Pumper, Cummins 855 Turbo
There used to be a link here, to some useful IDI-diesel tech info; but it was chopped out by others, in a vain attempt to repress the very essence of the internet: linking!
sigh...
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Analog; you quoted one source as saying to use 2-lo for "steep and slippery boat ramps". That's not quite right. You'd use it for -steep- ramps, but for -slippery- you'd want 4wd. Lo-range can actually exacerbate spin-out problems because there's just so much torque going to the wheels. It's hard to control it enough to prevent break-loose.
On a slippery ramp, I use 4-lo, but I don't worry about it even in turns, because it's.....slippery! [img]/ubbthreads/images/graemlins/biggrin.gif[/img]
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Heh, the source quoted was my poor brain [img]/ubbthreads/images/graemlins/eek.gif[/img]. You make a very good point, and of course, slippery is just what 4-lo is good for. Thanks for clarifying.
__________________
Ryan
1988 F250 Supercab, 4x4, 7.3 IDI, C6 Auto, 147K miles
Banks Sidewinder non-wastegated Turbo, Stage 1 Injectors, and Pyro, Boost and Water guages.
Having 4x4 locked (Lo or High) and engaged will bind most systems while on solid dry surfaces. If your driveway is loose or wet, etc. you should be OK in 4x4 Lo/locked. I would do 2LO as you describe, if your driveway is paved, etc.
Enjoy your 4x4!!! [img]/ubbthreads/images/graemlins/cool.gif[/img]
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"You gotta get your mind right" Cool Hand Luke
(Paul Newman)
1988 4x4 F350, 7.3IDI, ZF 5spd(5th syncro gone), SRW, 4.10 LS (worn clutches) Std. Cab Stock, Rough Paint Rough bed. 190,000 miles Multiple fuel/air leak/supply issues. Did the soup bowl.
New ZD-9's. New Batts. Fuel returns and inj cups repaced sometime ago. Donations accepted.
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