Using 4wd to slow down

[craig7h]

I was reading the last issue of trailer life, the article a couple wrote about looking for a new truck. In the article they said that when going down a step grade they will put their truck in 4wd low and low gear to help slow down. I would like to know if this is common practice. I would have never thought about doing that, is this something that the trucks transmission can handle.

[2gypsies1]

Totally agree....4lo when 4-wheeling off pavement....not on an interstate.

[nevadanick]

Exhaust Brake and Tow Haul

[mowermech]

Muddydogs wrote:
I have to say that most of you guys have no idea what you're talking about.

First most new pickups have auto locking hubs which means when you engage the 4x4 stick or switch in the cab the hubs engage as well.

Ford does have auto and manual hubs in one package. Why Ford did this is for the convenience of auto hubs but when you bury the truck in a hole and can't roll the truck enough to get the hubs locked in one can get out and lock them in.

Using 4lo to ascend or descend a steep forest road is not foolish at all. All your doing is gearing down the transmission getting more torque or power to the wheels. Yes the front end is locked in and on pavement if you make a sharp turn the wheels will hop as there spinning together so don't make sharp turns, heck even just having a rig in 4 hi will cause tire bind on pavement.

I guess that none of you have had to crawl up a steep road with the trailer in tow, well if you can only go 4 or so miles an hour up the hill with your foot on the floor try shifting in 4lo then select a transmission gear that gets you the torque and speed you want. Same works for doing down hill, shift into 4lo then select a transmission gear that keeps your speed down so you are only touching the brakes a little.

4lo and first gear in the transmission will get you about 3 or so miles an hour before everything starts winding up, 4lo and 5th gear will get you around 25 miles an hour before wind up. Most manufacturers recommend keeping your speed under 25 mph when in 4lo.

It amazes me some of the answers people give on this forum that have probably never even had a pickup in 4lo. Obviously most of the guys that have posted have never towed down a steep 5mph forest road for 10 miles or more.

The answer is really quite simple:
1. READ the owners manual.
2. FOLLOW the instructions contained therein regarding the use of four wheel drive, and specifically the LO range in the transfer case.

If you haven't read it, you might be surprised at what it says!
I have owned 4X4 vehicles since about 1970, mostly Jeeps, Chevys, and Dodges, and I have never seen one that had a "2Lo" transfer case position, nor have I ever seen one that didn't say using LO range without having the hubs locked in was a BAD IDEA! ("It had 2 hi, 2 low, neutral, 4 hi, and 4 low." I would like to see proof of that!)

Yes, I HAVE done a considerable amount of driving on logging roads in the mountains of Northwestern Montana, mostly for fishing or cutting firewood, but some just for sight-seeing. I rarely had to use 4Lo.
However, on the "slick-rock" near Moab, Utah, the use of 4Lo was rather common, if not absolutely necessary.
Yeah, in a small way I been there, done that.
I still say that using 4Lo to go down Homestake Pass on I-90 East of Butte or Lookout Pass on I-90 or the Vantage hill on I-90 in Washington would be a damfool idea!
Read the instructions!

[sammytoo]

bpounds wrote:
Manual hubs have not been available on a Superduty since at least 2005. Not even with a manual shifter. I know because I would have swapped out my auto hubs a long time ago if they made them. That's where the 2WD/low range modification comes in that I mentioned above. I have not done that mod but it is pretty simple.

Don't know about other brands, but would bet they are similar.

My 06 Super Duty has manual hubs

[mpierce]

I wish my 4 whl drive vehicles had the transfer case my, I believe, 84 chev had.

It had 2 hi, 2 low, neutral, 4 hi, and 4 low.

Most now do not have the 2 low. That was a GREAT selection for slow speed manauvers. Lots of power, no locked in axles.

[kofire]

I gave up early on this one. No reason to try and convince people who never leave the pavement the options available to them with some trucks.

[tdsxt51]

Muddydogs wrote:
I have to say that most of you guys have no idea what you're talking about.

First most new pickups have auto locking hubs which means when you engage the 4x4 stick or switch in the cab the hubs engage as well.

Ford does have auto and manual hubs in one package. Why Ford did this is for the convenience of auto hubs but when you bury the truck in a hole and can't roll the truck enough to get the hubs locked in one can get out and lock them in.

Using 4lo to ascend or descend a steep forest road is not foolish at all. All your doing is gearing down the transmission getting more torque or power to the wheels. Yes the front end is locked in and on pavement if you make a sharp turn the wheels will hop as there spinning together so don't make sharp turns, heck even just having a rig in 4 hi will cause tire bind on pavement.

I guess that none of you have had to crawl up a steep road with the trailer in tow, well if you can only go 4 or so miles an hour up the hill with your foot on the floor try shifting in 4lo then select a transmission gear that gets you the torque and speed you want. Same works for doing down hill, shift into 4lo then select a transmission gear that keeps your speed down so you are only touching the brakes a little.

4lo and first gear in the transmission will get you about 3 or so miles an hour before everything starts winding up, 4lo and 5th gear will get you around 25 miles an hour before wind up. Most manufacturers recommend keeping your speed under 25 mph when in 4lo.

It amazes me some of the answers people give on this forum that have probably never even had a pickup in 4lo. Obviously most of the guys that have posted have never towed down a steep 5mph forest road for 10 miles or more.

I agree 100%, but I got the impression the OP was talking about driving on pavement. Of course you don't use 4WD high or low on pavement. Unless it's snowpacked. Do people really not understand this concept?!? Eegads! 4WD IS FOR OFF ROAD!

[bpounds]

Muddydogs wrote:
I guess that none of you have had to crawl up a steep road with the trailer in tow,...

I'm with you, but not very many people here ever do anything like that, as I mentioned above. I guess it isn't too surprising, since this is a fifth wheel specific sub-forum. Most of the fivers here are too big for that kind of fun. And that's why I kept our unit small and light.

[bpounds]

fireman41 wrote:


This is my 2013 F250 hubs. Just free and lock, no auto no vacuum

I stand corrected, and I appreciate the photo. I wonder why those can't be retrofitted into a truck with auto hubs? Or maybe they can? The vacuum system in the Ford auto hubs is not very reliable.

[Muddydogs]

I have to say that most of you guys have no idea what you're talking about.

First most new pickups have auto locking hubs which means when you engage the 4x4 stick or switch in the cab the hubs engage as well.

Ford does have auto and manual hubs in one package. Why Ford did this is for the convenience of auto hubs but when you bury the truck in a hole and can't roll the truck enough to get the hubs locked in one can get out and lock them in.

Using 4lo to ascend or descend a steep forest road is not foolish at all. All your doing is gearing down the transmission getting more torque or power to the wheels. Yes the front end is locked in and on pavement if you make a sharp turn the wheels will hop as there spinning together so don't make sharp turns, heck even just having a rig in 4 hi will cause tire bind on pavement.

I guess that none of you have had to crawl up a steep road with the trailer in tow, well if you can only go 4 or so miles an hour up the hill with your foot on the floor try shifting in 4lo then select a transmission gear that gets you the torque and speed you want. Same works for doing down hill, shift into 4lo then select a transmission gear that keeps your speed down so you are only touching the brakes a little.

4lo and first gear in the transmission will get you about 3 or so miles an hour before everything starts winding up, 4lo and 5th gear will get you around 25 miles an hour before wind up. Most manufacturers recommend keeping your speed under 25 mph when in 4lo.

It amazes me some of the answers people give on this forum that have probably never even had a pickup in 4lo. Obviously most of the guys that have posted have never towed down a steep 5mph forest road for 10 miles or more.

[Arcamper]

fireman41 wrote:

Arcamper wrote:

bpounds wrote:

fireman41 wrote:

Not true my 2013 has full manual hubs. Unless you physically turn in the hubs the front axle will not be engaged.

Is it a Superduty? If so, I think you are mistaken. If you look at the hub dial closely you will see it has AUTO and LOCK positions. You can force them locked, but you cannot force them unlocked.

But I've been wrong before.

The Ford Superduty system that had Auto and Lock on the hubs was a vacuum operated system. They were free spinning until you put the shift on the fly selector in 4wd hi or low. Then a small electric valve under the hood, passenger side right next to the vacuum pump applied vacuum to the front hubs. The lock position was a safety in case of failure in the auto system. You could pull the connector off that valve and put the truck in 4 low without locking in the front wheels thus forcing low range without actually being in 4 wheel drive.
It was not the best system out there and I had problems with it twice.

This is my 2013 F250 hubs. Just free and lock, no auto no vacuum

This is correct, if your truck does not have shift on the fly 4wd you would have standard hubs shown in this picture. I wish I would have had that system on mine. There is not much to go wrong. Only downside is unless you leave them locked in you have to stop and get out of the truck when you put it in 4 wd to lock the hubs.

[fireman41]

Arcamper wrote:

bpounds wrote:

fireman41 wrote:

Not true my 2013 has full manual hubs. Unless you physically turn in the hubs the front axle will not be engaged.

Is it a Superduty? If so, I think you are mistaken. If you look at the hub dial closely you will see it has AUTO and LOCK positions. You can force them locked, but you cannot force them unlocked.

But I've been wrong before.

The Ford Superduty system that had Auto and Lock on the hubs was a vacuum operated system. They were free spinning until you put the shift on the fly selector in 4wd hi or low. Then a small electric valve under the hood, passenger side right next to the vacuum pump applied vacuum to the front hubs. The lock position was a safety in case of failure in the auto system. You could pull the connector off that valve and put the truck in 4 low without locking in the front wheels thus forcing low range without actually being in 4 wheel drive.
It was not the best system out there and I had problems with it twice.

This is my 2013 F250 hubs. Just free and lock, no auto no vacuum

[Longhaultranspo]

My 08 Super Duty has manual trans, manual 4x4 and manual hubs.

[Arcamper]

bpounds wrote:

fireman41 wrote:

Not true my 2013 has full manual hubs. Unless you physically turn in the hubs the front axle will not be engaged.

Is it a Superduty? If so, I think you are mistaken. If you look at the hub dial closely you will see it has AUTO and LOCK positions. You can force them locked, but you cannot force them unlocked.

But I've been wrong before.

The Ford Superduty system that had Auto and Lock on the hubs was a vacuum operated system. They were free spinning until you put the shift on the fly selector in 4wd hi or low. Then a small electric valve under the hood, passenger side right next to the vacuum pump applied vacuum to the front hubs. The lock position was a safety in case of failure in the auto system. You could pull the connector off that valve and put the truck in 4 low without locking in the front wheels thus forcing low range without actually being in 4 wheel drive.
It was not the best system out there and I had problems with it twice.