Newb dummy question: Is xj really a 4x4?

[klonestar]

When in 4x4 does all 4 tires work? I vaguely recall many 4x4's are actually 3x4's (three wheels drive)

Checked my rear D35 and back tires spin opposite so it is a limited slip? I did read all the posts on what percentage goes to front/rear in different 4wd set up. Does limited slip mean only 3 tires working at a time?

Its a stock 90' xj so far. 4.0 auto

Thanks,
Ken

[Sarge]

Without a traction assisting device in the front and back in 4x4 most are actually 4x2 (4 driven by 2) with one wheel on each end driving the vehicle. Of course that's assuming a slippage somewhere.

Sarge

[klonestar]

Thanks and that doesnt sound good for real off roading! Gotta get that fixed!

Ken

[Tally_XJ]

It works well as long as all four tires are on the ground!

If you have an automatic tranny version, you can apply light brake if one tire is off the ground and it will help the other tire that is on the ground to get traction (sometimes).

Still, a locker in both front and rear will provide the best amount of pull.

[creeperjeep]

Tip: When a vehicle with an open carrier flexes so much that one or more wheels comes off the ground, you can apply the brake and throttle to stop the wheel that's off the ground from spinning and allow the wheel with traction to continue to move.
Warning....Click here to see possible side effects. (http://creeperjeep.net/Images/tech/blownspiders.jpg)

[ROBZ95Xj]

Checked my rear D35 and back tires spin opposite so it is a limited slip?
NO limeted slip for you.

[klonestar]

NO limeted slip for you.
So means what? My 4x4 is a 4x2 yes? Bummer! Gotta get that fixed!

Thanks,
Ken

startin to miss my old 74 chevy true 4x4! posi and locking front hubs.

[jeeplvr88]

when the tires spin in opposite directions when freewheeling, it means you have an open diff, no LS or locker. with either of those both would spin in the same direction.

[ROBZ95Xj]

So means what? My 4x4 is a 4x2 yes? Bummer! Gotta get that fixed!

Thanks,
Ken

startin to miss my old 74 chevy true 4x4! posi and locking front hubs.
know anyone with a welder?:D j/k

[klonestar]

when the tires spin in opposite directions when freewheeling, it means you have an open diff, no LS or locker. with either of those both would spin in the same direction.
Bare with me im on a major learning curve here....

So with an open differential power goes to tire w/least resistance?

Which is why above items say to brake to stop spinning tire so power will then go to the other side?

Same is true for front D30?

You talking 'tapping' the break pedal or actually quickly laying on it?

thanks again,
Ken

[klonestar]

Tip: When a vehicle with an open carrier flexes so much that one or more wheels comes off the ground, you can apply the brake and throttle to stop the wheel that's off the ground from spinning and allow the wheel with traction to continue to move.
Warning....Click here to see possible side effects. (http://creeperjeep.net/Images/tech/blownspiders.jpg)
So possible side effect is from hitting the tire w/traction too fast or hard?

My luck I'll do that first time out!:shocked:

Following threads and using search it appears its not a good investment sinking $$$$ into D35 and D30 for lockers eh? (sigh!)

Ok so I got a 360 400hp and a dodge 8 3/4 rear end to start with if I junk my 66' Coronet! (slice n dice) lol kiddin!

[8Mud]

Differential action is a whole course in mechanical engineering.
But the gist of it is, if all four tires are pointed straight ahead, on an even surface with equal traction it's a 4X. Whenever your turning a corner the outside tire turns more times than the inside (front and rear) and the bias for the differential is to the side with the most revolutions (or the tire that turns with the least resistance). Which is most times a good thing, except when you want maximum acceleration or traction.
Applying the brakes moderatly (and progressively) can help force a portion of the bias to the tire turning fewer revolutions (or with the most traction). Getting the a tire spinning or the entire drivetrain and suddenly catching traction (or braking hard) or decelrating it quickly and a whole bunch of kinetic enenrgy comes to a sudden stop (or slowdown). Something has got to give.
Turning the steering wheel right and left (moderatly) can also help with traction.
Got to remember differential action is dynamic and is changing all the time.
A limited slip will force a ratio of torque to the tire with the most traction (or the fwest revolutions).
Also got to remember, the engineers designed the whole thing for an open differntial and/or a limited slip. Excess torque (or a large portion of it) is gonna be dumped to the tire with the least traction. When it's suddenly dumped to the tire (or axle) with the most traction, things break. In the real world the axles/tires are rarely turning at the same rate and the differential action, acts like a fuse to dump excess torque.
Guys spend years, building a drivetrain without a weak link and rarley succeed.
Even a 2X four wheel drive is better than a 1X 2 wheel drive.

[ILLXJ]

A locker in the 30 will be fine. I wouldn't put that money into a 35. JIM.

[klonestar]

Differential action is a whole course in mechanical engineering.
But the gist of it is, if all four tires are pointed straight ahead, on an even surface with equal traction it's a 4X. Whenever your turning a corner the outside tire turns more times than the inside (front and rear) and the bias for the differential is to the side with the most revolutions (or the tire that turns with the least resistance). Which is most times a good thing, except when you want maximum acceleration or traction.
Applying the brakes moderatly (and progressively) can help force a portion of the bias to the tire turning fewer revolutions (or with the most traction). Getting the a tire spinning or the entire drivetrain and suddenly catching traction (or braking hard) or decelrating it quickly and a whole bunch of kinetic enenrgy comes to a sudden stop (or slowdown). Something has got to give.
Turning the steering wheel right and left (moderatly) can also help with traction.
Got to remember differential action is dynamic and is changing all the time.
A limited slip will force a ratio of torque to the tire with the most traction (or the fwest revolutions).
Also got to remember, the engineers designed the whole thing for an open differntial and/or a limited slip. Excess torque (or a large portion of it) is gonna be dumped to the tire with the least traction. When it's suddenly dumped to the tire (or axle) with the most traction, things break. In the real world the axles/tires are rarely turning at the same rate and the differential action, acts like a fuse to dump excess torque.
Guys spend years, building a drivetrain without a weak link and rarley succeed.
Even a 2X four wheel drive is better than a 1X 2 wheel drive.
Gotcha! Makes much more sense now! Many thanks.
Ken

[GreenXJ2K]

Depends what your doing. Wheel it open, break it, throw in a rear D44, lock front/rear. If you want true 4x4, it will take some amount of wallet opening. Or better yet, get a unimog, lift your leg and piss on any trail.

[klonestar]

A locker in the 30 will be fine. I wouldn't put that money into a 35. JIM.
Ok and now????:)

So a D44 in the rear before adding mods to the rear? Now if a D30 is smaller than a D35 why is it ok to keep and upgrade it? Guess im asking why not a 44 on the front to? or? I like what your saying because it means less money for me! Just trying to understand why a 30 is ok in the front.

I cant do any major mods for a while but hope to understand and make the right decisions for me when the time comes.

Although I will eventually have a good rock climber first I want to make use of what offroading is readily available to me in my area as this is what I hope to be doing most weekends. More muddy washed out dirt roads and mtn. climbing around here w/tons of streams to cross.

And, any issues locking the front with an open D35 in the rear? I want traction for the type of 4x4 ing I will mostly be doing where I live. I also need to keep it a DD for now.

Many thanks again,
Ken

[8Mud]

Locking the front and your steering disappears. Even with a limited slip it's slightly noticeable (more so in loose stuff), the more aggressive the device in the front the less steering you have. I had a Unimog with a mechanical/lever lock (solid) in the front and no power steering. It was almost like the steering wheel was in the locked posisiton, my skinny butt just wasn't up to turning it much. And when I did get the wheel turned, it wanted to go straight ahead anyway. Not for the streets.
Even an aggresive limited slip or ratchet locker in the rear can mess you up in the snow or rain. Gas it at the wrong time and you swap ends pretty quick. Most of my wheeling is done on snow or in the mud. A limited slip rear and an open front are my preferance. The traction gains with a more aggresive setup are negated by the lack of control. I use momentum, the right tires and the gas pedal to get me through. I also don't often break drivetrain parts.

[klonestar]

Locking the front and your steering disappears. Even with a limited slip it's slightly noticeable (more so in loose stuff), the more aggressive the device in the front the less steering you have. I had a Unimog with a mechanical/lever lock (solid) in the front and no power steering. It was almost like the steering wheel was in the locked posisiton, my skinny butt just wasn't up to turning it much. And when I did get the wheel turned, it wanted to go straight ahead anyway. Not for the streets.
Even an aggresive limited slip or ratchet locker in the rear can mess you up in the snow or rain. Gas it at the wrong time and you swap ends pretty quick. Most of my wheeling is done on snow or in the mud. A limited slip rear and an open front are my preferance. The traction gains with a more aggresive setup are negated by the lack of control. I use momentum, the right tires and the gas pedal to get me through. I also don't often break drivetrain parts.

So as I do need to keep this as a DD in major snow country Id be better off leaving the front alone and working on a limited slip for the rear? Best bet would be to get a 44 and limited slip for the rear?

Is the known axle breakage (35/30) mostly done in rock climbing?

I mean I can get a one front wheel drive mini van into places in snow and ice that most find unbelievable just by using the methods you mentioned. I do understand the driver part. My dad taught me old school when you didnt have all this modern stuff. He said you want to get over there this is how you do it and we never had a 4wd vehicle! I drove my 66' Dodge year around w/limited slip and it handled great on snow and ice!

Thanks,
Ken

[8Mud]

I have a 8.25 in the wifes 96 and a 35 in mine, I've never managed to break either one yet. I don't go over a 30 inch tire. The gains from a taller tire are marginal for me, as most of the clearance I need is at the axle (rutted roads). And the taller the tire, the worse the handling, it's a tradeoff.
Though I've had a bit of wear on the 35. New carrier bearings, new spider gears, soon new pinion bearings. The 8.25 seems to be heavier duty and seems to last better (though I did lunch one in a Dodge PU once). If my 35 ever does explode, I'll be looking for an 8.25 or a 44. Or even maybe a dually rear out of a Mercedes 2 ton truck. I spotted one at a junk yard with the right width and a mechanical/ lever locker:loveu:

[RCP Phx]

So means what? My 4x4 is a 4x2 yes? Bummer! Gotta get that fixed!

Thanks,
Ken

startin to miss my old 74 chevy true 4x4! posi and locking front hubs.
Your Chevy is/was no different(4x2) without lockers.

[klonestar]

Your Chevy is/was no different(4x2) without lockers.
Never did dig into the rearend of the chevy. Never needed to. But in 4low granny gear all 4 tires spun at the same speed at the same time. When I hit the gas I knew I had all four wheel traction. Its a nice feeling. Had great tires that got traction in/on everything I needed. It had been heavily moded before I got it. I just beefed up the tranny and the engine. Had no 4wd on dry pavement. Could only spin rear two tires then. Took a lot to get them to spin though. They just wanted to grip n go. Actually won many rounds of beer betting it was really a 4x4! Had buddies in Jeeps and Fords betting me it wasnt. Never lost a bet! Top speed was 90. Would still do 90 up steep hills pulling a 30' travel trailer! Semi's couldnt believe it.:)

[whatevah]

extra weight and easy on the gas always helps traction :)

[Matthew Currie]

Never did dig into the rearend of the chevy. Never needed to. But in 4low granny gear all 4 tires spun at the same speed at the same time. When I hit the gas I knew I had all four wheel traction. Its a nice feeling. Had great tires that got traction in/on everything I needed. It had been heavily moded before I got it. I just beefed up the tranny and the engine. Had no 4wd on dry pavement. Could only spin rear two tires then. Took a lot to get them to spin though. They just wanted to grip n go. Actually won many rounds of beer betting it was really a 4x4! Had buddies in Jeeps and Fords betting me it wasnt. Never lost a bet! Top speed was 90. Would still do 90 up steep hills pulling a 30' travel trailer! Semi's couldnt believe it.:)

Locking front hubs do not lock the differential. Their business is only at the axle ends.

Actually, "locking hubs" is a misnomer. They should be called, as the original Warn hubs for CJ's were, I believe, "free wheeling hubs." The default position for a 4WD axle is engaged, in the manner of any full floating axle, with the hub permanently driven by the splines on the axle shaft. Later model XJ's are this way. The original Jeeps, among others, came this way, and freewheeling hubs were offered as an aftermarket option to disengage the hubs from the axle shafts when on the road.

It is, of course, possible that you had a limited slip differential on the front of that Chevy, along with the back, and if so, you would indeed have had true 4 wheel drive, at least straight ahead. some of those old systems, such as Dana's Pow-r-lok, were mighty grippy. But that's something else.

[sjan]

YOUR CHEVY HAD POSI--FRONT AND REAR ???

[red91]

theorhetically all vehicles with 4 wheels are 4 wheel drive.

Take one wheel off and your not gonna get very far.

:confused1

[XJ_ranger]

Ok and now????:)

So a D44 in the rear before adding mods to the rear? Now if a D30 is smaller than a D35 why is it ok to keep and upgrade it? Guess im asking why not a 44 on the front to? or? I like what your saying because it means less money for me! Just trying to understand why a 30 is ok in the front.


locking the front even though the differential isnt as strong as the d35, there is most often less weight on the front axle in positions where axle pieces go boom.

ofcourse there are people who will say that they blew a d30 shaft, ring and pinion, bla bla bla - but the majority of users with locked dana 30's dont have too much of an issue with them...

Jim (ILLXJ) has a locked 30 front and did some real hard wheeling on it a few weekends ago, no issues...

[teookie]

Jeeps ARE 4X4!!!!!! Quite saying their not! It's killing me!!

Even if you drive on some pretty slippery stuff, the only time you don't have full 4 wheel drive is if one tire slips considerably. If it just slips for one revolution your power loss is negligable and your only 2x4 for that split second.

Limited slip does just what it says, limits the slippage of that axle thereby reducing the likelyhood that you will only have one axle pulling.

You don't wan't a full time locker in the front. If you wan't to see what it would feel like, drive on pavement with the T case in part time. (just don't break anything while you do this...)

You can learn a lot about differentials (open, limited slip, locked etc etc etc) with google. Don't expect a full understanding to come quickly though, these are fairly complicated devices!!

[90Pioneer]

Limited slip in the rear and an air locker in the front. Expensive, but this would provide you with maximum traction when you're out wheeling, and on the pavement. When you hit the streets you could flip the locker off and you'll never know it's there. But you'll still have your limited slip helping you out on the snowy roads.

[klonestar]

Tons of great info everyone! Im starting to understand it much better now. Thanks for all the good input and info.

[dizzymac]

Where in the White Mtns........Campton here.

[klonestar]

Where in the White Mtns........Campton here.
North Conway. Where is Campton?