Pulling a 5th wheel on level highway

Wish to thank all those who gave me their experience and/or information.
Gary

garycq wrote:
I have a 30' 5th wheel and pull it with my Dodge diesel truck. The rear end gearing is 4:10 and the trans is an automatic which has been rebuilt for heavy towing. I was told recently by an experienced RVer that I should never tow my 5'ver in over drive. I usually tow at 55mph or less and I do use over drive on level highways. He told me he has torn up a couple of trans by using overdrive. I was curious about other peoples experience about towing with an automatic. When going up any grade the over drive goes off.
Thanks
Gary

Pulling in overdrive or not depends on your RPM. If the RPM is to low then you want to get out of overdrive. Having a 4:10 gear and running on the highway say at 65mph. You would probably be turning a lot of RPMs if you were not in overdrvie.

Path1
Learned from my dad years ago to change the automatic fluid and filter once a year. I do it every December as well as a number of other things. I, as a rule of thumb always try to stay about 50-55 mph when towing. I try to get behind a big rig that is going about that speed and draft behind him. Even when not towing and with 4:10 gearing I very seldom go over 70 mph. The best I ever got when towing was on a 6 week vacation, 12 mpg overall. I automatically never drove over 60 but was staying about 55.
Gary

OP... I already posted on this thread once but your post got me thinking that its about time to adjust the trans bands again. I forgot the torque so I broke out the book. Book fell open to trans section and re-building the "overdrive unit". I've only looked at it casually before.

After paying attention of about seeing about 10 pages just on the overdrive. There is no way I'm pulling with anything with it engaged. Got fewer disks and a lot of stuff packed into small area. I'm surprised they last as long as they do.

And I'm sure you know that Dodge hides stuff in the owners manual. No surprise there but if you don't know, you do now. Here is one example:

If you follow Service schedule B (heavy duty) at back of book it says to change trans fluid and filter at 30,000 miles but way back in another chapter under "starting and operating" it says:

"If your vehicle has an automatic and you tow a trailer frequently, change transmission fluid and filter every 12,000 miles or (19,000 km) that's just one example. That's a big difference. And trans fluid is the life blood of transmissions.

And after spending a couple days camping with a retired Cummins guy.

(Funny who you meet sometimes camping. He was walking by and said Thanks for buying and I'm retired Cummins)....

hearing his stories about some of the projects he worked on, there is no way I'm going to worry about a mile or two better MPG in overdrive. False economy, you'll spend more than that you save re-building the trans. My brother in law with his 7.3 gets about 1 to 1 1/2 better MPG than I do. That is pretty consistent tank to tank. And that is when we are following each other, same road and same conditions. He loves to rub it in. But my Trailer is also 2,000 pounds heavier and about a foot higher. He only locks out after trans kicks down one gear.

Anyways happy camping

My signature isn't complete. I thought it was but I guess I didn't do it right. I will add the below information once I learn how to do it right!
Gary

2007 29-5T, 125 Solar Panels, Inverter, 5th Airborne Sidewinder Combo, Brake Smart Controller, Michelin 16" XPS RIB tires
2001 Dodge CTD 2500, LB, Dana 80 4.10, AirBags, Smarty, DTT Hvy Duty Trans w/Smart Controller, Mag-Hyrtec Trans & Differential Covers, 4 inch Exhaust, PacBrake, 60 Gal Tank

When towing with a 47RE in OD, we need to be aware if the TC is locked or not. When it is there is very little stress on the trans provided the rpms are in the power band. IMHO 1700 is to low with my 355s.(my 98.5 24 valve) It will lock but seems to lug. Lugging is not good. Also in the 47RE the converter locks in 3rd and OD.
OD with the converter not locked due to torque management is something I don't do. Turn the OD off and let it lock in 3rd. The trans will thank you.
I keep thinking about 4.10s, but I'm running very close to stock tires. I hate to give up the mpg, and the truck seems happy pulling just under 12K lbs with the 3.55s.
As others have stated, trans temps and EGTs are your indicators of impending doom.

mdamerell wrote:
I put it in "Tow Haul" set the cruise about 60-62 mph (2,000 rpm w/ 4:10 rears) and let her run. The truck will do what it feels is right. Towing 12,000# and normally it will only drop 1 gear to go up a hill. If it's in tow haul the computer will protect the engine and transmission.

no tow haul in 2001

On flat to hill run in 4th. When you start climbing drop to third. A pyrometer will help you determining where your engine rpm's should be.

RustyJC wrote:

Coach-man wrote:
OP never stated year of his truck, newermodels of RAM and most other models have a tow/haul button which is used when towing or hauling anything! Older models have OD off or lockout switch which is the same thing.

Ummm, nope, not by a long shot. The 47RE OD lockout button locks out OD - period. Tow/haul mode in my truck (see signature) does NOT lock out 5th or 6th gears (both overdrives); it modifies shift points, shift firmness, exhaust brake function and interaction with the service brake pedal, provides an automatic exhaust brake/transmission downshift function to decelerate or to hold speed on a downgrade, etc. The newer trucks are much more sophisticated than the 2nd generation Dodge with its simple OD lockout switch (yes, I had one in my 1996 Dodge V-10/47RE-equipped 3500 dually).

In 2004 and 2005, Cummins and Hemi powered Rams went through a transition period where many had "O/D Off" on the end of the shift lever but would not lock out O/D but would instead go into tow/haul mode. Even after the supply of mismarked shift levers gut used up and the proper "Tow/Haul" lever showed up on new trucks, the howling about not being able to lock out O/D convinced Chrysler to offer a flash to diesel powered pickups to lock out O/D with the push of the button. Gas powered trucks didn't get the flash which is odd considering the Hemi was the one that needed the ability to lock out O/D. I wrote to Chrysler to no avail. At least one year if I remember correctly had the ability to go to Tow/Haul with one push and Tow/Haul with O/D off with a second push. A third push put it back to normal operation. That may have been the 2006 Hemi powered HD pickup.

We towed in O/D with our '95 47RH, '98 (5spd manual), 2001 and 2003 47RE Cummins Rams. Same with our '05 Hemi powered 2500HD and our current 5.4L gas powered F250. Both of which have no ability to lock out O/D. Never had a transmission problem.

My old rig was an F150 and 30' FW. I towed in OD roughly 50% of the time on the flat. Never had a tray problem.