I know this is a newbie question, but it just came up. How can I tell when my 4x4 is working?
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4x4 HOW DO I KNOW ITS WORKING
- Thread starter Biff
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If I understand correctly, you have a 94 FZ, Does it have a CDL switch?
- Thread starter
- #3
No it does not have a CDL.
It's AWD, so it's always working...
If you have locking hubs and you're asking if they're locked, I think the various idiot lights (ABS, etc.) light up when you're locked, but someone with lockers will have to verify this since I don't have 'em. The other way you'll know is if you start scuffing your tires as you turn on pavement (which you don't want to do too much).
If you have locking hubs and you're asking if they're locked, I think the various idiot lights (ABS, etc.) light up when you're locked, but someone with lockers will have to verify this since I don't have 'em. The other way you'll know is if you start scuffing your tires as you turn on pavement (which you don't want to do too much).
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- #5
Good to know, Thanks
Scamper said:
I don't think that's really true. Correct me if I'm wrong . . .
We have AWD, but the only way to get 4WD as it's commonly referred to is to turn on the Center Differential Lock (not talking about a Center Differential Locker) which we have a button for or is turned on automatically when you shift into 4LOW.
The difference between AWD and 4WD, as I undertand it, is that potentially you could have only one wheel spinning and have no traction (no power to any other wheels). While in 4WD you would need two wheels spinnig before you lost traction (one wheel in back and one wheel in front).
This is because we have a Center differential, which does what the diffs in the front and rear axles do (lets wheels spin at different speeds).
Does that sound right?
semlin
curmudgeon
I don't think so. Lots of 4wd vehicles have open diffs and a CDL is an exception not a rule. the line between AWD and 4WD is blurry for me but I think AWD systems tend to have limited slip or traction contolr limiting the amount of time you get drive to all 4 wheels to "as required". the 80 has a fulltime conventional 4wd system all the time.
I don't think we're disagreeing. We have AWD which in 4H means we have 2WD (center diff is present, but more like a LSD unless locked due to viscous coupler...so maybe 1.5WD? 
). In 4L you're really just locking the center diff for those of us without lockers.
The only way to get true 4WD on an 80 is if you have lockers...which is why I suspect that's what he was really asking.
). In 4L you're really just locking the center diff for those of us without lockers.The only way to get true 4WD on an 80 is if you have lockers...which is why I suspect that's what he was really asking.
On the issue of AWD being equivalent to 4WD I will respectfully disagree. That's why they make lockers. I think the article supports what I said unless I'm totally wrong about how the LC drive train works (that's a possibility I can't ignore too 
).
As the article notes, when the axles are not locked, the wheels are capable of slipping, and you don't have 4WD (I was being techical about it). To say otherwise would be equivalent to saying that a Chevy Vega has 2WD (like a posi) since on dry pavement the diff will distribute power to both wheels on the drive axle. The benefit of locking axles is that in just that case where one of the wheels will spin, the locked diff keeps both wheels moving. So when our AWD trucks are not locked in 4H, we are really driving one wheel on each axle.
Biff's original question was whether his "4x4 was working", which could mean a couple of different things depending on whether he has lockers or not (turns out he doesn't). The simple/obvious answer is that it's always working becuase we have AWD as everyone agrees. But if he was asking whether the truck was in true, locked 4WD, then that depends on whether he has lockers which wasn't stated.
Yadda yadda yadda...
).As the article notes, when the axles are not locked, the wheels are capable of slipping, and you don't have 4WD (I was being techical about it). To say otherwise would be equivalent to saying that a Chevy Vega has 2WD (like a posi) since on dry pavement the diff will distribute power to both wheels on the drive axle. The benefit of locking axles is that in just that case where one of the wheels will spin, the locked diff keeps both wheels moving. So when our AWD trucks are not locked in 4H, we are really driving one wheel on each axle.
Biff's original question was whether his "4x4 was working", which could mean a couple of different things depending on whether he has lockers or not (turns out he doesn't). The simple/obvious answer is that it's always working becuase we have AWD as everyone agrees. But if he was asking whether the truck was in true, locked 4WD, then that depends on whether he has lockers which wasn't stated.
Yadda yadda yadda...
The 80 operates in AWD in normal daily operations. The "center differential" in the transfercase has a viscous coupling, which reduces the loss in the "center differential", providing a better distribution of power.
When the truck is in low range, the center differential is "Locked" and the 80 acts like any other 4WD vehicle in Low Range, 50% power to the front & rear axles.
The owner installed "Center Differential Lock" switch allows engagement of "TRUE" 4WD in hi-range, which provides power equally to the front & rear axles.
"Lockers" in the axle differentials allow equal power distribution to the wheels
When the truck is in low range, the center differential is "Locked" and the 80 acts like any other 4WD vehicle in Low Range, 50% power to the front & rear axles.
The owner installed "Center Differential Lock" switch allows engagement of "TRUE" 4WD in hi-range, which provides power equally to the front & rear axles.
"Lockers" in the axle differentials allow equal power distribution to the wheels
Big_Moose said:
That's what I was trying to say!! However, Big_Moose did a much better job of saying it.
Especially the second paragraph, about 'acting like any other 4WD vehicle.' Most vehicles called 4WD don't have lockers, I just meant what was commonly called 4WD (open diff axle diffs front and rear). Main difference is that we also have a center differential.
I think the biggest problem is the whole "Center Differential Lock". My understanding is that all 80's have a Center Diff Lock, which ""Locking" means is that the diff no longer performs the task of allowing the drive shafts to turn at different rates. The front and rear drive shafts are physically locked together. If one is to turn, the other must turn the same amount." (from link above) Some of the 93-97's have another switch which also locks the Front & Rear Diffs in addition to the Center Diff . . .
So my answer to the above question would be to go somewhere where you can get some wheels to spin. If you can be in 4Low and get stuck with only 1 wheel spinning then I believe that 4WD is not working, because the "Center Differential Lock" is not actuating.
As for the axles diffs, I thought that power in an "open" diff was distributed evenly between the two wheels unless there was slippage on one side, then the side that slips gets more or all the power. Also if both tires are slipping evenly then they both still get the same amount of power, until one side has less traction and then power 'slips' to the wheel on that side. Does that sound right?
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- Thread starter
- #14
Well I guess the center diff lock was never been used. After trying it a few times the ABS, and Diff Lock ligts came on. To make my life easier I'm going to be ordering the center diff lock from slee offroad. I noticed I have the front/back diff lock lights, am I right to assume that the LC is already prewired for lockers if I want them in the future?
Biff said:
Victor,
Are you sure there are lamps behind the panel? All the dash panels are the same but non-diff lock optioned vehicles did not come with lamps in the dash.
Even if you, by some chance, have the lamps, your truck is not completely prewired for lockers. There would still be an ECU and wiring required to enable the lockers after you buy the mechanical bits and pieces.
-B-
- Thread starter
- #16
Beowulf
Yes I'm sure I have the front & rear diff lock lamps. If I'm not prewired for lockers what does it mean to have those lamps on my dashboard?
Thanks for your info.
Yes I'm sure I have the front & rear diff lock lamps. If I'm not prewired for lockers what does it mean to have those lamps on my dashboard?
Thanks for your info.
Not trying to sound like a smarta$$, but if you do not have the diff lock option and you have those lamps then it probably only means you have the dash lamps.
What is the axle code on the sticker inside the driver's door?
-B-
What is the axle code on the sticker inside the driver's door?
-B-
- Thread starter
- #18
Hardly, I figured it was nothing special and that I just had the lamps.
What axle codes go with what rigs that have locks and those that don't?
What axle codes go with what rigs that have locks and those that don't?
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- Thread starter
- #19
My mistake, I only have the icons and the transmission is K292 which is open diffs. Oh well I guess ARB locks are in the future for me.
Here is a CDL question. Do you get better gas mileage if the CDL is off (AWD), can you somehow convert it to 2WD (just rear) to save on gas?
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