Truck Driving Jobs

#11 12-09-2007, 03:22 PM

Quote:

Originally Posted by SteveBooth

Thanks Dweller. I was just going to say screw it and go my merry way and let everyone tell stories instead of actually PICKING UP A MANUAL AND ACTUALLY READING IT!!!!!!!!!!!!!

I dont think anyone told any STORIES....we are going by what we have learned and were told, if this qualifies as making up a story...sorry I didnt mean to lie to you all even though i didnt know i was making it up and lying.

I am still curious just as to why you would lock that in going over 50 mph if you thought it was actually slick enough to use it. This is not a smart ass question I am just very curious about this....maybe i can learn a new thing or 2 about driving in slick conditions on this thread.

Fredog · #12 12-09-2007, 03:35 PM

Quote:

Originally Posted by Jagerbomber

Quote:

Originally Posted by SteveBooth

Thanks Dweller. I was just going to say screw it and go my merry way and let everyone tell stories instead of actually PICKING UP A MANUAL AND ACTUALLY READING IT!!!!!!!!!!!!!

I dont think anyone told any STORIES....we are going by what we have learned and were told, if this qualifies as making up a story...sorry I didnt mean to lie to you all even though i didnt know i was making it up and lying.

I am still curious just as to why you would lock that in going over 50 mph if you thought it was actually slick enough to use it. This is not a smart ass question I am just very curious about this....maybe i can learn a new thing or 2 about driving in slick conditions on this thread.

last winter, I was driving on a 2 lane road in the middle of nowhere about 11 at night, the weather was dry and the road looked fine, when I went to slow down for a curve, my tractor started to go sideways. I recovered and and then I locked in the axles. I figured there must be icy patches, I dont know if it did any good to turn it on, but it made me feel better. then I went on to the customer and got stuck in the snow on the rxr tracks, (luckily, their private tracks) but that's another story

#13 12-09-2007, 05:36 PM

Ok, I went and got out the old freightliner manual....different things for different rear ends and traction control devices....the only one in my manual that specificly says its ok to kick in at any speed is the Dana Spicer axles with Controlled Traction Differential.

On the other hand, Dana Spicer Interaxle Differential Lockout, different from controlled traction differential, specificly states, Engage only when stopped or at slow speeds and never on dry pavement or for prolonged periods of time.

On Meritor, the one that states specificly that you should lock in only at a stand still and never over 25 mph is the [b]Main Differential Lock[/b, different from Interaxle Diff lock whichis i guess what we were thinking about on the beginning of the thread.

The only one in the manual that specifies that it is ok to use at any speed is the Dana Spicer with Controlled Traction Differential which is apparently a different thing from interaxle diff lock.

Long story short, everybody was part right and part wrong...just depends on which option your truck is equiped with.

The one constand with all of these things is that none of them are really recomended for exteneded use and nver on dry pavement...and they do cause extra wear on the drive train....So Just take a peek in your manual like stated above, i did that and learned a few things...now i just have to figure out if i have a Dana Spicer or Merritor set up.

#14 12-09-2007, 05:57 PM

Quote:

Originally Posted by Jagerbomber

I dont think anyone told any STORIES....we are going by what we have learned and were told, if this qualifies as making up a story...sorry I didnt mean to lie to you all even though i didnt know i was making it up and lying.

Sorry JaggingBoomber, didn't mean for it to come out that way. Most of the time what I really want to say doesn't come out in my posts.

#15 12-09-2007, 06:05 PM

no problem...hey At least i went and got out that manual and did do some reading instead of just arguing my side. I always went by what the company told us about using the darn thing and it just didnt occur to me to read up on it since I very very rarely touch it anyway. Good info to have if you are in the snow alot.

GhostCaptain · #16 12-10-2007, 07:10 PM

Last year when I got my CDL and not much experience with trucks, I was traying to leave my yard and the rear wheels started spinning in some mud, engaged the diferencial lock,got out and completelly forgot to unlock it until 400 miles later in Houston,Texas, nothing happened to the differentials

Doghouse · #17 12-10-2007, 10:53 PM

I hope I didn't ruin mine. Today when I picked up my trailer I had to use it in the snowy yard and then I drove 9 miles on dry pavement before I noticed that I left it on.

Mackman · #18 12-10-2007, 11:30 PM

i know in my MACK with the diff. lock on a loud azz buzzer comes on and stays on intill you take the diff. lock off.

Orangetxguy · #19 12-13-2007, 12:02 AM

Quote:

Originally Posted by Part Time Dweller

Instructions for the inter axle lockout/ Power divider. Provided by Eaton Dana.

http://www.roadranger.com/ecm/groups..._axdr-0126.pdf

Quote:

Use lockout when approaching: ice, snow, mud, wet surfaces, or loose terrain.

Lockout Operation
1. Temporarily release the accelerator pedal. This interrupts the torque
applied to the inter-axle differential allowing easy engagement or disengagement
at any speed.

2. Flip the lockout selector valve to lock (engage) or unlock (disengage)
the lockout.

Remember:
• Engage lockout at any speed with accelerator released. Never
engage lockout when wheels are slipping.
• Use only under poor traction. Do not operate truck with lockout
“engaged” on dry pavement.

How it works;

Tandem axles will rotate at different speeds when cornering, driving over
uneven road surfaces or when equipped with different tire sizes.
The inter-axle differential is simply a mechanism that lets one axle rotate faster
or slower than the other. Under normal conditions it splits the torque evenly
between the 2 axles.
When extra traction is needed under adverse road conditions, you can lock out
the inter-axle differential. With the lockout engaged (LOCK position), the interaxle
differential acts as a solid shaft and does not compensate for differences
in axle speed, but directs the torque to the axle with the most traction.
With the lockout disengaged (UNLOCK position), the inter-axle differential
operates normally.

There also is a differential lock that locks the rear ends side to side. This is usually not installed on an OTR truck, but can be. This will be a seperate control from the power divider. This is the one you can't use over 25mph, and trust them when they say you will have severe understeer with it on.

Instructions for differential lock, Provided by Eaton Dana
http://www.roadranger.com/ecm/groups..._axdr-0130.pdf

Quote:

The Dana Drive Axle Wheel Differential Lock is an air-actuated clutch which
positively locks the differential gearing in the rear axle. When this clutch is
engaged, power flows to the tires without any differential action, giving each
wheel all the torque the road conditions will permit.

The Wheel Differential Lock is engaged by a cab-mounted valve, causing the
clutch to move in or out of engagement. This motion also trips an electrical
switch used to activate a light in the cab or sound an audible device, indicating
that the Wheel Differential Lock is engaged.

WARNING: Do NOT use your Wheel Differential Lock when traveling
downhill

WARNING: Do NOT use your Wheel Differential Lock at speeds over
25 mph

Engage
1. Flip the control lever to the “Lock” position, either while the vehicle
is stationary, or while moving at a steady speed under 25 miles per
hour without the wheels slipping (spin out).
2. Let up momentarily on the accelerator pedal to relieve torque on the
gearing and fully engage the clutch.
3. When the differential lock is engaged, the indicator light will be on, or
an audible signal will sound.
4. When the differential lock is engaged, the vehicle will understeer,
requiring a longer turning radius for a given turn.

Disengage
1. To disengage the Wheel Differential Lock, flip the control lever to
“Unlock”.
2. Let up momentarily on the accelerator pedal to relieve torque and
allow the clutch to disengage.
3. When the differential lock is disengaged, the indicator light and/or
audible signal will go out.
WARNING: Engage Wheel Differential Lock ONLY when vehicle is
stationary, or moving without wheel slippage.

Important To Remember
When engaged, the Wheel Differential Lock will cause the vehicle to understeer,
meaning that the vehicle will not turn as quickly, and more steering
effort will be required.
Use your Wheel Differential Lock only at speeds less than 25 miles per
hour; at higher speeds, the understeer handling characteristics could be
dangerous.
The differential lock should be engaged only when the vehicle is stationary,
or moving without wheel slippage (spin out).
This system should only be used when poor traction is encountered; it
should be disengaged under normal traction conditions.

Power Dividers today are far and away superior to the power dividers of the 60's, 70's and early 80's. Technology ...go figure.

Now...the Wheel Differential Lock..that is sweet, if you are chained up, pulling 105,000 pounds, and climbing a mountain. It makes it tough though, if you have it engaged and try to turn a 90 degree corner. Lot's of crow hopping, even at slow crawl.

allan5oh · #20 12-13-2007, 01:19 AM

Yup you definitely don't want to have this thing engaged while it's slick out and you're going around corners. You greatly increase your odds of jacknifing under power.

It's the axle lock that you don't want to leave engaged. Most trucks nowadays will disengage the axle lock automatically at about 15 mph.