shortbed rv

I put an LED light that comes on when the TC is locked. Then I added the TC lockswitch just for the situation you descibed. However if the Rpm drop below 1700 you need to downshift.

SOhappy

What are you using for rolling resistance to get 400HP at 60mph? It's a common rule-of-thumb that on tractor trailers the aerodynamic loading doesn't surpass rolling resistance until 65 mph. That's what I meant by "hardly noticeable" at 60mph. Just exaggerating a little to get my point across.

LeonT

That "little hill" you're talking about is Telegraph Pass. The grade is much steeper than you realize. I've pulled loads over it with semis, Power Strokes, Duramaxes, and this Cummins I have now. If your brother is pulling that grade at 80 MPH with a toyhauler I'd say he has some serious mods. I have never pulled that grade with a load anywhere approaching 80 MPH. I don't think there is anything wrong with your truck. You'll see a lot of vehicles pulling that grade empty and they are really huffing and puffing to keep their speed up.

I was born in Yuma and grew up in a little fart of a town named Tacna about 40 miles east of there. I've pulled that grade hundreds of times. My vote is to relax about it. I think you're good (although I realize the testosterone levels tend to rise sharply when approaching a "grade" and pulling a "load" with your "diesel" truck). I've been there. Finally learned to relax.

firedoger

Thanks for all the help and advice. I may be going back to the dunes in a couple of weeks and I hope to have a smarty jr on it by then. I'll check and replace the filters and see what happens.

AH64ID

Good luck...

SOhappy

By "hills" let's say 2+ miles of >5% grade. Otherwise, yes 2100 rpms is perfect. That's about where I'm at towing 75mph on the interstate, and can maintain that speed on overpasses and other slight rises without kicking down.

If you guys can tow 10,000 lbs up 2 miles a 5% grade at 65mph at 2100 rpms then I guess you have my slightly-modded SO beat (that's not saying much). As for me, I need the extra RPMs to maintain the speed limit on western mountain passes.

BTW, not telling you anything you don't already know- but these trucks hit peak HP at 2900 rpm. That's what's going to get you up that pass, not peak torque (at 1900 rpm).

SOhappy

I'm measuring that as a 2% avg. grade, eastbound (350' rise over 3.75 miles), 3% westbound (530' rise over 3.5 miles). You're right, such a slight grade over that distance can be deceiving.

jumper

Enough talk; I just want to hook up a trailer and go pull a hill. I can't wait for boating season. Till then, I'll just have to play in the snow. That's its own brand of fun.

LeonT

Correct. I assume he's talking about the westbound portion. It really starts dragging you down and there are some curves to deal with as well.

On the eastbound side there is a Border Patrol inspection station just before you start climbing, so you have to slow down or stop prior to hitting the grade.

NDanecker

Frontal area plays a HUGE roll when pulling. Weight comes in when going up steep grades. Put them together and you've got one tough pull!

I've got a 24' v-nose all aluminum Thule that is 7'6" clear inside. Its probably not as tall as some fifth wheel toy haulers, but its very lite (3500 empty). This thing is like a parachute!!! Huge difference between pulling this emtpy and an open 30' gooseneck deckover with 13k of steel coils (which have little or no wind drag as its very low to deck). the coils pulled very nice on flat ground but hit some steep hills you knew it was there. Down hill and ya needed exhaust brake. Downhill with the Thule ya still need to push on the go-pedal!

I dumped the edge juice for smarty jr and extremely happy with the tow mode. That is my suggestion.

Good luck!!!!!

NickBeek

Don't pull that heavy with a programmer or chip without gauges! That would be a BAD idea. Also putting your foot to the floor and holding it there will not net you the same results as a gasser will (can't speak to the GM). I find I get much better performance towing if I keep just enough pressure on the go pedal to make it want to accelerate, like just beyond where it would only maintain speed. I believe there is some "protective" software written into our ecm that slightly de-rates the engine if you just floor it and hold it there. Replace your filters, air up your tires to at least 70PSI assuming you have the proper "E" rated tires, and make sure you have good fuel then tow again using the strategy above and see what your results are. I'd be interested in hearing about it.

billie

That's just like when I walked to school.....up hill both ways

Hounddog

Wonder why once they start leaking they don't stop even after replacement.I read of a few on other sites who had NUMEROUS seals and said to heck with it and traded trucks.Friend of mine has had SEVERAL front and back in his 05 Dually from 80k to 150k.Anybody with AAM reading this?

Ace

Most likely incorrect installation. When new, those teflon-faced seals have to be put on a perfectly clean, dry surface in order to set properly. I suspect most techs doing this just pull out the old ones and stuff in the new ones without another thought to it.

Rednax

These trucks are already overpowered from the factory. Compared to driving a big rig, speed is the easiest thing in the world to maintain. But why would anyone want to speed up the hill, or mountain? Agreed that finding the best rpm spot is worthwhile. Torque is what gets you over the hill, horsepower only tells you how fast . . . and beating on the motor to keep it at 60 mph (for example) is dumb if the engine is indicating hots spots inside the motor.

As for trailers, it is irresponsible not to KNOW the numbers. It is unfortunate that nothing tells the RV owner how much work he actually has to do to get things properly rigged. If, as the insurance industry indicates, 90% of hitched RV's are improperly rigged, then anyone who doesn't know the numbers is part of that sorry number. It isn't that much work (find a certified scale), should be done on a regular basis, etc. Sort of like not tightening the trailer wheel lug nuts before every trip . . eventually, it is a problem.

I made a point of buying an aerodynamic, all-aluminum travel trailer. At 34' it weighs -- full-timing -- 7,400#. The truck is overkill for hauling this but I also needed it for work. Interstate mileage, level ground, is around 15-mpg. Secondary roads is 13 mpg (stop & go in towns).

Even then, with this better towing rig, I drop to Direct to hit the hills at above 2000 . . not to maintain speed, but to make life easy for the engine. The speed drops off as a matter of gear choice, but, then, that is how a diesel best operates, IMO, as throttle opening is just the way to move between gears.

Here's a chart to work with if you have a bumper-pull trailer:

Get all the numbers, and try NickCrowhursts Calculator; you'll have a leg up on 90% of the rigs on the road once you've made the proper adjustments.

Crowhurst Calc: Excel spreadsheet
http://www.airforums.com/forums/f464...sis-19236.html

1. TT Length, Hitch Ball Center to TT Rear Bumper:

2. TT Tongue Weight:

3. TT Hitch Center to Rear Axle Center:

4. TV wheelbase:

5. TV Rear Spring Capacity:

6. TV Rear Overhang (axle center to hitch center):

7. Length of bars:


A. TV Steer Axle, Solo:
[1] TV Steer Axle, Loaded:

B. TV Drive Axle, Solo:
[1] TV Steer Axle, Loaded:

C. TV Weight Bias, FF/RR, Solo:
[1] Loaded:

D. TV Weight, Solo, Gross:

E. TV Weight, Loaded, Gross:


F. TT, Tongue Weight:

G. TT, Axle Weight (all axles):

H. TT, Axle Weight (front):

I. TT, Axle Weight (rear):

J. [TT, Axle Weight (center):]


I. TV, FF, height, solo:

II. TV, FF, height, loaded:

III. TV, RR, height, solo:

IV. TV, RR, height, loaded:

V. TT, height (fenderwell), solo:

VI. TT, height (fenderwell), loaded:

The two dozen numbers can be useful for further tuning or understanding.

If your trailer tongue weight is 500# or higher then a load-distributing hitch is required by Dodge. That is a result of analysing "loss-of-control" accidents.

Not to mention that, if you get the weights balanced out, and rigging proper, you can see a reduction of fuel usage. The important part is making driving smoother.

Tires should be pressurized to the recommended number, not some Internet guys idea of same. Big money is spent to understand these relations in industry. Necessary tools for towing, IMO: infrared thermometer, tire tread depth gauge, torque wrench, dead-accurate pressure gauge . . . and readings before, during and after a day on the road.

Electric brakes need to be checked for consistent voltage under application (hot & cold); checked for drag, etc. Hubs, same.

Trailers need shock absorbers, wheel/tire balancing AND AXLE ALIGNMENT.

All of these will, when finally dialed-in, make towing a lot easier on the driver. That will mean better consistency behind the wheel (mpg).

Adding boxes, etc, is a waste.