A friend of mine has the exact truck as I do. He towed my toy hauler home this weekend and forgot to put the truck back in 2 wheel drive before leaving the desert. He drove about 200 miles, average speed of 65, in 4 wheel drive. Everything seemed fine. Could this have done any damage?

Thanks

I hope not, from personal experience... Turning sharp corners on pavement doesn't seem to nice in 4wd though, going straight though, you'd never know its in.

You can feel it when turning, but I'm just making sure there was no damage done to the front differential or transfer case.

I've always heard that you're ok driving in 4wd. Figure that if trucks can go to the track and do quarter mile passes in 4wd you'll be all right on the freeway. Also, heard that if you're really worried about it to just change the fluids. I know I've done it and it hasn't been a problem.

Should we check the fluids in the front dif. and transfer case? Anywhere else?

I do it all the time. Just yesterday the roads were snow packed and cars in the ditch all over the place, slipped it into 4 and ran 65 for 100 mi. It shouldnt hurt a thing.
I did change that milk colored fluid in the front diff for some AMSOIL some time ago.

I do it all the time. Just yesterday the roads were snow packed and cars in the ditch all over the place, slipped it into 4 and ran 65 for 100 mi. It shouldnt hurt a thing.


I've done the same thing :o: and never had any problems. :)

I did it too. No problems.

you may waste more fuel than before, and you can mess up drivetrain but you should be ok.

if the road is that icy that you need 4x4 to get around and drive 65mph you probly shouldnt be driving on the road at all. 4x4 will do nothing for your stopping ability. we have winter 5 months of the year here so i know a thing or two about winter driving.

if the road is that icy that you need 4x4 to get around and drive 65mph you probly shouldnt be driving on the road at all. 4x4 will do nothing for your stopping ability. we have winter 5 months of the year here so i know a thing or two about winter driving.


Hahaha, I hear ya man!!

As for using the 4x4 on the highway for a stretch, not a big deal at all. It's meant for that. As long as the tires are the same diameter, all is good. :)

I could be wrong but doesnt the front drivetrain spin all the time anyways? If thats the case I dont see how driving in 4wd is any different than driving in 2wd.

change front dif fluid, because its not used often, collects moisture, contaminates fluid, but u should b ok if mostly straight.

if the road is that icy that you need 4x4 to get around and drive 65mph you probly shouldnt be driving on the road at all. 4x4 will do nothing for your stopping ability. we have winter 5 months of the year here so i know a thing or two about winter driving.
truck will stop shorter in 4wd then in 2wd, provides equeal stopping power to all 4 wheels

truck will stop shorter in 4wd then in 2wd, provides equeal stopping power to all 4 wheels

x2:D

truck will stop shorter in 4wd then in 2wd, provides equeal stopping power to all 4 wheels

Never mind the fact that you have anti-lock brakes, and the fact that about 60-70% of your stopping power is over your front wheels...

Now on the 4wd on pavement...NO it won't hurt anything at all save for your mileage and treadwear. You don't need to change any fluid, the drivelines are all fine, You could drive around all summer long in 4wd and not cause any catastrophic damage.

truck will stop shorter in 4wd then in 2wd, provides equeal stopping power to all 4 wheels


WTF?
Are you being serious?

if the road is that icy that you need 4x4 to get around and drive 65mph you probly shouldnt be driving on the road at all. 4x4 will do nothing for your stopping ability. we have winter 5 months of the year here so i know a thing or two about winter driving.


:funnypost

I never said anything about stopping.

Oh ya I almost forgot I know nothing about snow or winter driving, After all its only Wyoming. It’s like the San Diego of the Rockies.

"we have winter 5 months of the bla bla bla"
And
"You shouldn’t be driving on the road"

You sound just like my dad. saying stuff like;

"I had to walk to school every day in the snow uphill both ways."

Here is a pic (picture) of beach front property, Enjoy pops!

its called common sense!

My brother roasted his front differential (litterally smoking) after about 20 miles on a windy road pully a 5th wheel in 4WD. It was so bad GM didn't even try and rebuild it. His truck was a 95, so I don't know if anything has changed since that would prevent this. If you were mostly straight, like going to Vegas, probably no problem. If there were windy sections, I would definitely change the diff and xfer case fluids. Good luck!

My brother roasted his front differential (litterally smoking) after about 20 miles on a windy road pully a 5th wheel in 4WD. It was so bad GM didn't even try and rebuild it. His truck was a 95, so I don't know if anything has changed since that would prevent this. If you were mostly straight, like going to Vegas, probably no problem. If there were windy sections, I would definitely change the diff and xfer case fluids. Good luck!

Do you know for a fact that there was sufficient oil in the diff before the run was made? cause my '94 stays in 4wd all winter long and has never had a problem one. and my '04 has driven around in the summer in 4wd multiple times and its still rollin without any problems.

:funnypost

I never said anything about stopping.

Oh ya I almost forgot I know nothing about snow or winter driving, After all its only Wyoming. It’s like the San Diego of the Rockies.

"we have winter 5 months of the bla bla bla"
And
"You shouldn’t be driving on the road"

You sound just like my dad. saying stuff like;

"I had to walk to school every day in the snow uphill both ways."

Here is a pic (picture) of beach front property, Enjoy pops!




Haha yeah that look's like home and just because the roads r bad dosent mean we cant drive on em unless they are closed, just put the chains on and keep on rollin lol, Obviously nobody here has drove on a Wyoming road in white out conditions on solid ice it sux, expecially going over some of the moutain passes in those conditions but hey we dont know wat were talkin about!

i never said you guys dont know about winter driving. i said that if you need 4x4 to go 65mph. then chances are the road is in pretty shity conditions and if it is that shitty then your gonna have a hard time stopping.

i never said you guys dont know about winter driving. i said that if you need 4x4 to go 65mph. then chances are the road is in pretty shity conditions and if it is that shitty then your gonna have a hard time stopping.

Yeah most of the time 65 is too fast one time i had to drive 400 miles across the state at 20-40mph

Do you know for a fact that there was sufficient oil in the diff before the run was made? cause my '94 stays in 4wd all winter long and has never had a problem one. and my '04 has driven around in the summer in 4wd multiple times and its still rollin without any problems.


I hauled a 15,000 pound goosneck about 100 miles through grades anywheres fomr 5-8% in 4 wheel and didnt have any problems, I just couldnt figure out why my fuel gauge was going down so fast.:rolleyes: Man that push buttons nice but i wish there was a 4 wheel light on the dash and not just a little light in the button.

WTF?
Are you being serious?

very, think about it

so your sayin my brakes only work on the front when im in 4x4?

Your truck is fine, it won't hurt it in 4X4.

My experience driving is snow is next to nothing. But the one time i did, the best part of it was sliding into the snow drifts on the side of the highway at 4-50 mph. There was no one else dumb enough to be out there :)

This is kinda funny... you drove 200 miles with no sharp turns? My truck is a real bear to turn when 4wd is engaged on pavement.

It's definitely not good for it, but that doesn't mean it will break tomorrow. Don't let this scare you...

Usually the gear ratios between the front and back are not exactly matched and you end up with a slight load on one of the axles and thus on the transfer case.
Consider first a 265/75/16 and a 31x10.5x16 (height difference of only 1/2 an inch). The difference in speed at 2000rpm in 5th w/ 3.73 axles is 1.5mph. (This could probably cause a failure very quickly.)
or with a 3.74 rear axle and a 3.72 front on 33 inch tires, a difference of 0.5 mph.

The difference in loading/speed has to be absorbed by one or more of the following:
-Tires (Slipping, additional wear)
-Transfer case (the weakest part in it takes the most load)
-Differential
Trying to figure out what happens next is anyones guess. If there is no slack/slip or failure in the axles or t-case, then you have two tires that are sliding while rotating... there goes some breaking and handling ability.
To give an example of this sliding, consider your front tires are locked up and your rears are rolling at 1.5mph. Now speed both ends up an additional 70mph. The only thing that has changed is that the front tires are now constantly changing the point on the tire which is sliding, but they are still sliding!

If the t-case is slipping a clutch then your creating a lot of heat and wear on it. (the NP 246 has a clutch, but i dont think our 263's do...)

Best advice is to be damn careful.

truck will stop shorter in 4wd then in 2wd, provides equeal stopping power to all 4 wheels


wait I thought our trucks had brakes on all the wheels? :rolleyes:

wait I thought our trucks had brakes on all the wheels? :rolleyes:

It seems logical that the ABS system would make the braking force equal to all wheels when in 4wd. Applying more force to the front wheels doesnt make sense when they are physically geared to the rear wheels.

It seems logical that the ABS system would make the braking force equal to all wheels when in 4wd. Applying more force to the front wheels doesnt make sense when they are physically geared to the rear wheels.

What you end up with is inefficient braking. Given the fact that the front and rear wheels are no longer allowed to brake independently, their eficiency is reduced. That being said, on a 1984 4WD this theory DOES work. But they didn't have ABS, so....you figure it out.

and also, our trucks have dynamic rear proportioning. Meaning, front/rear brake bias is controlled electronically by the ABS module. If you slam on the brakes and the EBCM (abs module) detects that the rear wheels are about to lock up (which always happens because our trucks are way lighter in the rear), it automatically cranks the front/rear brake proportioning/bias full forward, and then does its thing cycling the dump valves and isolation valves to pulse the brakes and prevent you from skidding.

So on our trucks, the theory of "4wd giving you better braking" does not hold any water whatsoever. The 2009 dmax's go one step further with their stability control. (stabilitrak)

ben

downshifting would be better in 4wd though since the engine is directly linked to and therefore slowing down all four tires at the same time instead of only 2 tires. As for regular breaking i cant see there being any difference, 2wd vs. 4wd, because the abs is constantly regulating breaking pressure for each tire so that it can provide maximum stopping power without sliding.

downshifting would be better in 4wd though since the engine is directly linked to and therefore slowing down all four tires at the same time instead of only 2 tires.


:exactly:

Would anyone agree that driving on pavement in 4wd wears tires faster? Then you would agree that there is SOME sliding or frictional wear going on that isn't in 2wd?
It's a fact that you have a certain force capacity (for stopping, turning, accelerating, etc) per tire per pound of force over it that is based directly on your coefficient of friction. So if you're in 4wd and creating more sliding (kinetic friction) then you are operating on more of a KINETIC friction interface instead of a STATIC fiction interface. Kinetic friction coefficients are lower than static coefficients. Therefore, your coefficient of friction between your tires and the road should be lower in 4wd drive and your stopping and handling power must be partially diminished.

It seems logical that the ABS system would make the braking force equal to all wheels when in 4wd. Applying more force to the front wheels doesnt make sense when they are physically geared to the rear wheels.

Here is a really good point. If you engage the 4wd system, your abs can not function. If one is locked up they are all locked up. And if you were to lock up all four, the abs could not recover since it depends on independent wheel speed sensors for reference.

So maybe on dry pavement 4wd breaking in a straight line COULD be faster than 2wd with abs.
Otherwise.... i would think its more of a problem.

what a dumb ass!!!

lol we need to shut this one down guys. we're not helping anyone anymore.

Here is a really good point. If you engage the 4wd system, your abs can not function. If one is locked up they are all locked up. And if you were to lock up all four, the abs could not recover since it depends on independent wheel speed sensors for reference.

So maybe on dry pavement 4wd breaking in a straight line COULD be faster than 2wd with abs.
Otherwise.... i would think its more of a problem.

the ABS works fine in 4wd. Thats why we have a differential in the front axle...

ben

I thought the front differential was a spool/locker? Check this link.
http://www.dieselplace.com/forum/attachment.php?attachmentid=68420&d=1214918107
Certainly isn't open. I've had it jacked up and both wheels roll together when 4wd is engaged not to mention the howl from the inside tire while turning tight.
The functionality of the ABS system is affected by any driveline connection between two wheels.
If the wheels are locked together, then wheel speed at each wheel is irrelevant, since they are all directly related to the tail shaft speed.

The ABS does stuff even in 4wd, but the difference i noticed was black marks from both sides simultaneously, where as in 2wd there were random scattered marks. Plus it would 4 wheel slide that last 2 or 3 mph to a stop.

Maybe I'm completely wrong here...

Your 4 wheel drive truck has an open differential in the front.

The link you provided proves this fact. Notice part 25, this is the spider gears.

The transfer case doesn't have a differential. So this means one of the front tires and one of the back tires will be turning at the same speed no matter what. This is what causes the binding.

It will have a small effect on the abs system. In 2 wheel drive you can have all four wheels turning at different speeds. In 4 wheel drive you will have one of the fronts and one of the backs locked together. They aren't actually locked together, just traveling at the same speed. You can't determine which ones it will be because you have a front and rear differential.

You did an experiment with the truck on jack stands and both the front tires turned. This is the nature of an open differential, because both tires where off the ground they had equal torque. Try it again with only three tires on jack-stands, leave one of the front tires on the ground. If you have a locker in the front you will have a real mess. The tire on the ground will pull the truck off of the jack-stands.

I thought the front differential was a spool/locker? Check this link.
http://www.dieselplace.com/forum/attachment.php?attachmentid=68420&d=1214918107
Certainly isn't open. ...

yes it is. :)



The functionality of the ABS system is affected by any driveline connection between two wheels.
If the wheels are locked together, then wheel speed at each wheel is irrelevant, since they are all directly related to the tail shaft speed.

Yes I realize that, but our front is not locked, so the ABS works fine.

Tblack marks from both sides simultaneously, .

Yeah thats because we have THREE channel ABS on our trucks. Not four. ;)

ben

I hauled a 15,000 pound goosneck about 100 miles through grades anywheres fomr 5-8% in 4 wheel and didnt have any problems, I just couldnt figure out why my fuel gauge was going down so fast.:rolleyes: Man that push buttons nice but i wish there was a 4 wheel light on the dash and not just a little light in the button.

Below are links how to wire the 4WD light on your dash. Not sure if this will work on your 06.

http://dieselplace.com/forum/showthr...&highlight=4WD
http://dieselplace.com/forum/showthr...&highlight=4WD (http://dieselplace.com/forum/showthread.php?t=50901&highlight=4WD)

This one worked on my 2002. Start at post #24:
http://dieselplace.com/forum/showthr...&highlight=4WD (http://dieselplace.com/forum/showthread.php?t=48892&page=3&highlight=4WD)

I really appreciate yall clearin me up on that. next time I'll make sure i don't hijack a thread for it to happen :).

Sorry for the incorrect information everyone. That was me thinkin i knew what i was talkin about. It made sense in my head... didn't have all the facts though.

When I first read this post I thought how can you not realize your in 4wd.
Well it's easier than I thought. Pulled my equipment trailer out of the way at a job site and had to put the truck in 4wd b/c the trailer was in mud. Jumped out and went back to working.
Driving home pulling the trailer doing 65 mph or so on the highway, when I'd let off the pedal I'd was hearing an "extra sound" thats not there everyday. Got into the neighborhood and made a hard right hand turn and the left wheel felt like it was going to fold under the truck. Came down to a stop sign and made a left and it felt like the right wheel was going to fold under the truck.
Looked at the selector buttons....... drove home in 4wd.