Why shouldn't I use 2wd low range?

[illegalFSJ]

In the past, when I've wanted a bit lower gearing, but didn't need 4wd, I'd leave the front hubs unlocked, but shift the D20 transfer case into 4 low range to get the gearing advantage. This would make a 2wd with low range. Flipping through the vintage '77 owners manual, it says to NEVER do this. Why not?

[Lindel]

There's a slight chance that you'll damage the front hubs. Otherwise, you won't hurt the transfer case, at all.

[Stuka]

I have done it and my hubs havent been hurt. Although I dont have factory hubs, I have warns. You could just put a twin stick on the D20 and then control the front and rear axles seperately. That way you can have 2wd low range and the front shaft wouldent even turn.

[dnixon]

I have the vaccum disconnect front axle they made in the 82-83 years (roughly) so I can disconnect the driveshaft all together.. not having to worry about damaging the hubs.. But this is all dependent on having the NP208 stick operated transfer case versus the NP229 vaccum actuated that i currently have..

[BIGYELLOW78J10]

What if your hubs didn't fully unlock - and then you gassed it, sending power to the partially engaged hub. Not too good for it, I would say.
Of course, I haven't done this, and don't plan to, though my Jeeps are both Qtrac, my Toy truck has manual hubs. I could definitely see trashing the hubs it they weren't fully disengaged.

Just thinking out loud.

Later,

Daniel

[rockjeep44]

You'd be fine. I run my 208 in 2wd low all the time. Just make sure to fully unlock your front hubs. The manual basically says that to cover their butts because there are some stupid people out there that don't know what in the world they're doing and would mess something up.
-Andrew

[HeepofaJeep]

This is only kind of related, but I was wondering why not to leave the hubs locked when in not in four wheel drive. I only do it when I am going from one trail to another, because I am too lazy to get out. but that really isn't bad for it, is it?

[Peter Matusov]

having the transfer case in 4-LO will not hurt your front hubs, as long as they are locked or unlocked. no problem at all.

there's another problem with 2-LO. The Dana 44 is an axle that's just about adequate for a 1/2 ton truck. Using it alone in low range (with torque multiplied by low range gearing) is going to eventually snap the axleshafts.

Same as "gunning it" when front axle has no traction in low range. a 350 Buick or 360 AMC will snap an axle rather easily.

peter

[Stuka]

aheepofajeep: eaving the hubs locked wont hurt anything per say. But they do cause pre-mature wear ont he front axle and drive line. In the winter I leave my hubs locked for weeks at a time because I use 4wd allmost every day.

[Peter Matusov]

Stuka,

if there's no load on the front driveline, there's no wear. Almost no wear, that is.
My Chero has about 180kmi on the clock, about 2/3 of it was spent in full time 4WD, and the front u-joint are as tight as they get. No significant slop in the front R&P, either.

peter

[Stuka]

Actually gears wear faster when there isnt as much force on them. When they are free wheeling they have more "play" so to say so they bang around a bit more. Also when freewheeling the front the stress is put on the backk side of the teeth. And the way a hypoid gear setup is they arent nearly as strong and have a smaller contact patch, so the wear is more concentrated.

And theres no way a axle with 180k miles on it is gona have no play in it. My spider gears had quite a bit of slop in them at 167k miles. And that was int he rear...the front under goes greater speed differances thent he rear when turning.

Now I am not saying running with your hubs locked all the time is gona make your axle wear out in 30k miles or nothing. Just saying why put wear on something because your to lazy to unlock your hubs when going down the freeway at 70mph....