4x4 problems

[Ruben9237]

I’m getting like half of what I used to get I have the t case motor wired also to a 3 way toggle switch to turn it from 4hi to 4 lo and then the other brown wire switch is to “turn the front tires on” but my t case shift fine in and out of the 4lo gear just no spinning of the front tires I can feel it like 1/4 engage but I guess not enuf for the front tires to actually do anything

A little update… I checked the fluid on the t case and it’s completely black so I’m on the way to the autozone near me to get new fluid and change it

 

[Mbrooks420]

this lock front wheels View attachment 425574

He doesn’t have one of these. Like mentioned above, twice. His front end is ALWAYS LIVE. The transfer case ABSOLUTELY sends power to the front axle. Nothing else is involved. The transfer case does a lot more than “select the gearing”.

 

[Mbrooks420]

New fluid is very unlikely to do anything but waste your money. You’ve almost certainly ruined the clutch clicking in your switch while spinning the rears. Huge no no with these cases.

 

[Pete Deering]

He doesn’t have one of these. Like mentioned above, twice. His front end is ALWAYS LIVE. The transfer case ABSOLUTELY sends power to the front axle. Nothing else is involved. The transfer case does a lot more than “select the gearing”.

He never stated he has a awd

 

[Mbrooks420]

He never stated he has a awd

It’s a 1999. It’s automatic 4wd, just like all v6 1999s are.

 

[410Fortune]

Just fyi with an open differential in 4wd only one front tire will spin, the one with the least amount of traction

 

[C420sailor]

He has the 4405 (Auto 4WD) without the vacuum disconnect.

As mentioned above, 100% live axle. Clutch pack in the transfer case controls power to the wheels. Sounds like he burnt it up.

His custom wiring job (not the brown wire mod) makes me wonder if that had a hand in it. Which component determines the duty cycle of the 4WD clutch? I’m not very smart on the wiring for these cases

 

[J_C]

^ Yes, if it were not for hardwiring it to continuously lockup the clutch, in automatic mode it would ramp up duty cycle in 10% increments to get the front spinning some too, so not as much friction. It would've done it the moment the rears started spinning (20ms later) so much less of a speed mismatch too.

As others already stated, continuous 12V should never be applied if the rear wheels are already spinning much faster than the front.

Putting new fluid in will most likely result in it slipping even more. It needs a new clutch pack at a minimum, unless there is some wiring (or switch) fault resulting in less than 12V getting to the clutch coil, which "might" also explain it.

 

[03eddie]

Hey everyone I’m running into a big issue with my 99 xl.about a year ago I did the brown wire mod because my wiring was fried and it worked great.we recently got snow here in North Carolina and my 4x4 was working great until today when I hit the switch for the brown wire mod my front tires no longer spins like they should I checked the wiring,bc axles ,front drive shaft and fluid in the t case and don’t see anything wrong.any help would be greatly appreciated

Which route did you decide to take when doing the brown wire mod? I have an 03 Eddie and have been considering it.

 

[joney]

^ Yes, if it were not for hardwiring it to continuously lockup the clutch, in automatic mode it would ramp up duty cycle in 10% increments to get the front spinning some too, so not as much friction. It would've done it the moment the rears started spinning (20ms later) so much less of a speed mismatch too.

As others already stated, continuous 12V should never be applied if the rear wheels are already spinning much faster than the front.

Putting new fluid in will most likely result in it slipping even more. It needs a new clutch pack at a minimum, unless there is some wiring (or switch) fault resulting in less than 12V getting to the clutch coil, which "might" also explain it.

Had mine in automatic mode today, doing 40mph on hard packed thin snow...slid a bit on a corner (only doing 20 there) - should I have had it in 4Hi instead? Not sure how fast automatic mode goes into 4wd but seems like quite a bit of delay, half a second to a second - is that normal? This is my first 4wd, hope to be using it correctly.

 

[Mbrooks420]

It’s very fast, not even a full tire rotation at that speed. Anytime it’s slippery you can have it in 4 high.

 

[joney]

It’s very fast, not even a full tire rotation at that speed. Anytime it’s slippery you can have it in 4 high.

Whew! And your reply is even faster, thanks much! Not sure why my automatic setting seems delayed, but will just go to 4hi as long as I have a snow or glazed road to deal with, no speed limitation as to using 4hi I believe you meant.

 

[J_C]

Had mine in automatic mode today, doing 40mph on hard packed thin snow...slid a bit on a corner (only doing 20 there) - should I have had it in 4Hi instead? Not sure how fast automatic mode goes into 4wd but seems like quite a bit of delay, half a second to a second - is that normal? This is my first 4wd, hope to be using it correctly.

If I started slipping, I'd be so focused on regaining control that I wouldn't be able to gauge what fraction of a second it took to engage. On the other hand, you can be sliding and if not applying throttle, not have enough wheel speed mismatch yet to engage it, which could explain the delay.


If your clutch pack is worn out, it could seem like longer till it ramps up to effective torque, but I wouldn't jump to that conclusion (yet).

4WD high is fine to use as long as you don't have any patches of dry pavement, so wheels can spin freely. I usually just keep it in Auto until slippage is excessive during acceleration (or no dry patches of pavement anywhere), and slow down lower than 20MPH on corners. I also put it in 4 high and 4 low a few times in winter just to make sure that still works including the shift motor, but 4 low just driving a short distance, slow speed then the test is concluded.

 

[joney]

If I started slipping, I'd be so focused on regaining control that I wouldn't be able to gauge what fraction of a second it took to engage. On the other hand, you can be sliding and if not applying throttle, not have enough wheel speed mismatch yet to engage it, which could explain the delay.


If your clutch pack is worn out, it could seem like longer till it ramps up to effective torque, but I wouldn't jump to that conclusion (yet).

4WD high is fine to use as long as you don't have any patches of dry pavement, so wheels can spin freely. I usually just keep it in Auto until slippage is excessive during acceleration (or no dry patches of pavement anywhere), and slow down lower than 20MPH on corners. I also put it in 4 high and 4 low a few times in winter just to make sure that still works including the shift motor, but 4 low just driving a short distance, slow speed then the test is concluded.

Pretty sure that answers my question. Have slid twice in automatic mode, wasn't on the gas at the time. Today's slide was so short, I wasn't on the gas, probably only a couple of feet. Rattled me just a bit though. Have tested 4 low just on my hill where I park, seems to work also. Lucky I think, have no idea what previous 4x4 maintenance was done by previous owners! I've defaulted to driving it like a RWD car, which I drove exclusively from '76 to '03 when I got my first FWD car. Nice to know now I can use 4 Hi on a snow packed highway also!

 

[J_C]

^ It would be good to change the transfer case fluid and think about doing the differentials too. Even if only driven in auto/RWD the fluid eventually needs replaced.

 

[Mbrooks420]

I’ve used high up to 75mph on the highway without and issue. High isn’t really delicate, and if you happen to use it on a place with too much traction it’ll just pop and slip the clutch. I’ve used high on stretches of road that had bare spots without any issue. If you’re going straight there’s no reason for it to bind up.

 

[XLTrunner]

Joney...I'm just going to throw this out there. Since this is your first 4WD vehicle, do not believe for one minute that you can't/won't slide on packed snow or slushy/icey roads; regardless of which position your dash switch is in. The medians, ditches and body shops are always full of 4WD vehicles who's owners barrel along under a false sense of security and do not understand that 4WD is of minimal benefit when encountering slick winter driving conditions. It is, however, a great help in getting moving from a stop.

 

[C420sailor]

It probably engaged rapidly, but didn’t hook up (gain traction) immediately. 4WD is great, but Newtonian physics still applies.

I go to 4HI when I can’t see any pavement, but that’s just me.

 

[joney]

Joney...I'm just going to throw this out there. Since this is your first 4WD vehicle, do not believe for one minute that you can't/won't slide on packed snow or slushy/icey roads; regardless of which position your dash switch is in. The medians, ditches and body shops are always full of 4WD vehicles who's owners barrel along under a false sense of security and do not understand that 4WD is of minimal benefit when encountering slick winter driving conditions. It is, however, a great help in getting moving from a stop.

Yep, one reason I was doing 40-45 instead of the 50 limit. Hanging out in the right lane. Everyone else doing the posted limit of 50 at least. Was wondering what would happen to them if the light changed to red quick! Thanks everyone for the answers and advice!

 

[J_C]

Joney...I'm just going to throw this out there. Since this is your first 4WD vehicle, do not believe for one minute that you can't/won't slide on packed snow or slushy/icey roads; regardless of which position your dash switch is in. The medians, ditches and body shops are always full of 4WD vehicles who's owners barrel along under a false sense of security and do not understand that 4WD is of minimal benefit when encountering slick winter driving conditions. It is, however, a great help in getting moving from a stop.

While I agree, I think it is also driver error. There have been many times, where I started to slide, and my gut reaction was depend on the brakes, that they're there to stop you and you want sliding to stop, right?

Well that's not always the solution, sometimes powering out of the slide is the thing to do, stay off the brakes, give it a lot of throttle (for a very short period of time till you correct your direction, making sure not to over-compensate (which is very common) ) and drive your way out of it. This works best if there are no other motorists very nearby, in case you suddenly get more traction than you expected.

My main point is, I wouldn't call it a minimal benefit at all, compared to only having RWD. When it's really slick out, I can just go (at an appropriate, slow speed), confident I won't get stuck as long as I take it easy on curves.

There are two types of drivers, those new to having 4WD or AWD, which is a growing class since the era where SUV/etc became more popular, and then those of us who had 4WD in winter for a long time and have more practice, realizing that in some situations, last thing you want to do is apply brakes if you don't want to get stuck. Of course tires are a good 50+% of it too, and getting stuck beats hitting another motorist. Every situation has its own choices to make.