Winter driving means slow down

[stumps]

A long time ago, several months after I bought my first 4WD vehicle... a pickup truck..., it snowed.... And, for the first time ever, I was excited that I had to go someplace ...IN THE SNOW!

Not knowing quite what to expect, I took some little baby steps in the parking lot. I locked the hubs, put the truck in 4WD drive, and I was amazed that it had traction to burn. Confident, I packed the truck up, and went off on my journey. I was going slow, because I knew that I was on equal footing with all cars in the 4WB (braking) category. In fact, it was going so well, that I figured there was no need to keep the truck in 4WD (and burn all of that gas), so I shifted the transfer case back into 2WD. I guess I should mention that the hubs were manual, and were still locked...

BIG MISTAKE!

I came to the first slight hill, and I heard (and felt) a little brupp brupp sound. I didn't think anything of it, until I noticed that the rear of my truck was slowly starting to pass the front. I let off of the gas, and gently steered my wheels into the skid, as I always do in 2WD vehicles, but sadly that did nothing to control the spin, and I hit a guard rail.... Thankfully I was the only one on the road, was only going about 25MPH, and did very little damage.

What went wrong? I was going slow and steady, I was going straight, and I spun out of control anyway.

Ok. Here is the scoop: When you have a truck that has a front differential, locked hubs, and is in 2WD, you are actually in a worse state of affairs for driving in slippery conditions than a normal 2WD vehicle. The reason is the front differential's gears are busy pumping cold gear oil, and applying a very significant drag on the front wheels.

When I shifted out of 4WD, I changed the situation from my front wheels being driven in sync with my rear wheels, to my front wheels driving a differential full of cold oil. That heavy drag on the front wheels caused them to stop turning (remember the: brupp, brupp sound?).

Wheels that don't turn don't steer!

Let's bring this story back around to military vehicles... and in particular my favorite, the deuce:

Your stock deuce has its front hubs locked all of the time. When you are driving with the transfer case in the rear wheel drive position, your front wheels are dragging heavily because they are turning your front differential, and it is busy pumping cold gear oil. With the front wheels locked out, you are actually in much worse condition to be on slippery roads than a normal 2WD vehicle. Your front wheels will stop turning almost instantly when they get on ice.

The only way to regain control is to get your steering back, and the only way to get your steering back is to get your front wheels turning again. And the only way to get your front wheels turning again is to get back into all wheel drive.

My pickup truck, like the deuce, can be shifted in and out of 4WD at will... but... if the front wheels aren't turning, shifting into 4WD will grind the transfer case gears, possibly destructively. The only way to get my pickup truck back into 4WD when the front wheels stop turning, is to make the rear wheels stop turning before shifting... that means jamming on the brakes, shifting into 4WD, and then driving out of the skid. I'd bet that you won't remember to do that when it is your turn to start slowly spinning out of control.

I'm pretty sure the deuce transfer case suffers the same gear clash problem with shifting into all wheel drive when one set of wheels is turning, and the other isn't.

Avoid the problem: If the road conditions require all wheel drive, stay in all wheel drive.

-Chuck

 

[dittle]

You just raised a good point Chuck and I now have a question related to the end of your post. What is the max speed you can drive a deuce with the front end locked in? Not max safe speed but max mechanical speed. I'm assuming that since the front end is spinning all the time anyway there is no mechanical reason that you couldn't drive normal speed with the Xfer case engaged to the front. Now, it might be harder on your tires, and your thumbs if you get them stuck in the steering wheel but that is not what I'm asking about....thinking more about the parts in the driveline.

 

[stumps]

I can't think of any mechanical reason for a limit. Everything is turning whether you are in all wheel drive, or are not.

In the pickup truck world, trucks with positraction front differentials are very squirrely if you leave the hubs locked, as the losses between the right side, and left side of the differential seem to change at will.... causing wander. But, alas, the deuce doesn't have that problem.

I am of the opinion that if the road situation requires all wheel drive, sanity requires you to go slow.

-Chuck

 

[Stretch44875]

I'm the nut in the two wheel drive car passing everyone. Live in ohio and drive 90 miles one way to work in cleveland. No way am I going 25mph because some idiot has bald tires, or does not know how to drive in snow. If it's bad out, I slow to 45 mph. If it's just your typical snow, I'm doing the speed limit. If it's really bad out (the backup 4x4 truck would get stuck), I stay home and play with the deuce. That might happen once a year.

With all that being said, I haven't had an accident in the snow or put a car in the ditch since I was 18. So look out, if I pass ya, don't look for me in the ditch!

 

[stumps]

I'm the nut in the two wheel drive car passing everyone. Live in ohio and drive 90 miles one way to work in cleveland. No way am I going 25mph because some idiot has bald tires, or does not know how to drive in snow. If it's bad out, I slow to 45 mph. If it's just your typical snow, I'm doing the speed limit. If it's really bad out (the backup 4x4 truck would get stuck), I stay home and play with the deuce. That might happen once a year.

With all that being said, I haven't had an accident in the snow or put a car in the ditch since I was 18. So look out, if I pass ya, don't look for me in the ditch!

The guy driving 25 mph (who is in front of you) might just be driving 25 because he knows something about the road ahead that you don't.... not because he is an idiot with bald tires.

The shame is when you finally do make your fatal mistake, you will probably also kill the cautious guy driving 25 mph.

-Chuck

 

[Stretch44875]

The guy driving 25 mph (who is in front of you) might just be driving 25 because he knows something about the road ahead that you don't.... not because he is an idiot with bald tires.

The shame is when you finally do make your fatal mistake, you will probably also kill the cautious guy driving 25 mph.

-Chuck

Not a chance.

 

[Stretch44875]

Need to clarify a little. Snow comes in about a dozen different kinds. You can have gritty snow that is like driving on packed gravel, to the hard packed snow that is like ice, to light powder, to heavy slush. Each one is different to drive on. One thing I don't drive on quickly or at all, is black ice, or freezing rain- ice. That is some truly slippery stuff. I saw a parked semi slid into the ditch from the crown of the road. At that point I am driving very slow, and half the wheels are off the road.

I always check the traction of what I am driving on, and change for the conditions.

Another thing is my roads are mostly straight, level, and in the country. Which makes for some nice drifts. Busting through powder snow drifts is some of the most fun you can have in a vehicle.

I see a lot of ditched cars where they went to close to the ditch, and got pulled in by the heavier snow. Some of them over-correct, get out of the ditch, and spin into the opposite ditch. My dear wife managed to do this recently when another car forced her off the road.

Truly I think most drivers can not steer out of a skid. So if they lose any traction, they lock the brakes and hold on to the bitter end. There is a payoff to doing all those donuts and driving rear wheel drives.

ABS is god's gift to snow driving. Much easier to do a steering stop. Some cars do it better than others. Unfortunately, my latest car does not have ABS. Not a problem when I am driving, but messes the wife up.

My daughter recently got her permit. Ex-wife was freaking out that I was letting her drive in the snow. Best time to learn is what I figure. Took her on a back road and told her to stop from 35mph as fast as she could. That was entertaining. Had to take over the steering wheel a couple of times. But she learned how to pump the brakes and keep control. Then took her to an empty parking lot and had her do some fast turns. Also pulled the e-brake and sent her into a slide. Now she can steer out of a skid, and knows how a car feels when it's out of control.

At the beginning of every winter, half the drivers forget how to drive in snow. Mostly just slow drivers. By the end, most are driving around the speed's I do. But you still have a couple really slow ones in a 90 mile drive.

My previous posts sound like I just helter skelter through the snow. But I drive in the stuff at least a couple of days every week, for 3 months. And the local township roads are not salted, they may have snow on them all month.

My vehicles are prepared every fall for the snow. Most years that means at least a couple new tires. New wipers are mandatory, full size spares, shovels, winter clothing...

Can I say I will never crash in the snow? Heck no. But my chances of crashing are below the average snow driver.

Now I have the upmost respect for Stumps. I would say he's one of the smartest people on this board, and I've learned some stuff from his posts. I would also say he's wrong about me killing anyone, when it comes to me driving in the snow.

Unless you have the experience and skill, don't drive like me. So don't take my previous post as a recommendation to drive fast in bad weather.

Dennis

 

[stumps]

Hi Dennis,

I certainly do not hope that your fast driving in the snow causes you to make that "fatal mistake", but I also know that I will never convince you that you need to slow down when the pavement friction conditions worsen, so the probability of your making that "fatal mistake" is much higher than I would like for you.

I will leave you with something to ponder: If your desire is to travel the route home at the fastest safe speed, and you don't consider snow, with the loss of stability and friction it causes relative to dry roads, something that compels you to reduces that speed to stay safe, then you must be driving way below that fastest safe speed when there is no snow.

Why?

Safe travels,

-Chuck

 

[dittle]

I am of the opinion that if the road situation requires all wheel drive, sanity requires you to go slow.

-Chuck

Common sense dictates this to be true. I agree with your post completely. Thats why I put in my post about not regarding safety but just mechanically if it would handle it. There is no way in **** that if I have to be in 6x6 to go anywhere in my deuce am I going to drive it anywhere close to full speed. Last time I was out in conditions that required 6x6 I think I did 30 or so for the top. NDTs also mean no **** stopping.

 

[ElkHunter61523]

Most people are just steering wheel holders...Caution is the best course.

 

[TheRainbowBoxer]

I see a lot of ditched cars where they went to close to the ditch, and got pulled in by the heavier snow.
Dennis

Hey hey hey... I don't do that! At least not to my own cars LOL!

 

[dragon1124]

This looks like the forum to post this story.

I was on my way into work last night. It was snowing bad <round 1 of 2> tonight is going to be even worse. 12-20" of snow, with up to 3" per hour.

I pulled up to a stop light, and this dodge nitro pulls up next to me. This stretch of road runs between two forest preserves. I always drive slower in any inclimate weather, be it rain or snow. This hot rodder revs his engine, I guess trying to intimidate me. The light turns green, he floors it, surprisingly gets traction to get going. I just take my time as I know my m1009 wasnt built for racing anyways, I'm not in a hurry to crash, Not even 10 seconds later, the nitro loses control, and slams head first into a tree. I pull over, and the driver was ok. His nitro had a nice tree hood ornament though. I waited for the police to show up, since I was a witness, and informed the officers of what happened. The nitro driver ended up getting 3 tickets, not to mention a nice tow bill. I wish I would have taken pictures, but was already running late for work.

 

[rideni]

I drive a reasonable and prudent speed in the snow and generally faster then most other drivers. Never had an accident I just know how to drive, couple of years of road racing, autocross, rallycross, and a little bit of ice racing kind of learn you. That person doing 25mph on the interstate in the snow storm is a danger and shouldn't be on the road. Some one that knows how to drive is not going to be the problem.