Towing & Overdrive
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Towing & Overdrive
I just bought a 2003 Dodge Ram 2500 with the Cummins Diesel. When towing a 9500# trailer @ 65 mph 2750 rpm and 70 mph 3000 rpm. I feel the rpms are too high but they don't advise towing in over-drive. I need some suggestions
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From: New Holland, PA
Re:Towing & Overdrive
Here's some info from another thread:
The whole thread is at http://www.dodge-diesel.org/yabbse/i...4624#msg164624
Unless you've added a governor spring kit or a box that raises your max RPM capability, you won't hurt the engine by winding it up. The 5.9 was built to drag around medium duty trucks weighing up around 28,000 pounds. These trucks are usually geared so that top speed is 62 to 65 mph. When you drive a truck like this on the highway, you just floor it and hold the pedal down. They run for hundreds of thousands of miles this way, at max governed RPM.
Specific example: the company I work for has a Ford 26k GVW truck with the 5.9 and an automatic. The automatic is set up so RPM is never under 2500 under load, and the truck will do 62 mph foot to the floor. The only time this engine runs under 2500 RPM is idling at a light or coasting. The truck has around 120k on it with oil changes at 7500 miles if somebody remembers, and it runs fine.
The point of all this is to show you that the 5.9 is really overbuilt for what most of us are doing, and that towing all day at 3000 rpm is a picnic compared to what these engines were designed to survive.
Specific example: the company I work for has a Ford 26k GVW truck with the 5.9 and an automatic. The automatic is set up so RPM is never under 2500 under load, and the truck will do 62 mph foot to the floor. The only time this engine runs under 2500 RPM is idling at a light or coasting. The truck has around 120k on it with oil changes at 7500 miles if somebody remembers, and it runs fine.
The point of all this is to show you that the 5.9 is really overbuilt for what most of us are doing, and that towing all day at 3000 rpm is a picnic compared to what these engines were designed to survive.
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From: Disputanta, Virginia
Re:Towing & Overdrive
Welcome to the site RTCRam,
I think that you will find most of us tow in OD as long as the RPMs can be kept above about 1700-1750 and the tranny doesn't keep trying to go in and out of OD (hunting). I tow a 10K 5er and only lock out OD under these conditions.
There are a few threads in the towing forum that talk about this also. CLICK HERE
I think that you will find most of us tow in OD as long as the RPMs can be kept above about 1700-1750 and the tranny doesn't keep trying to go in and out of OD (hunting). I tow a 10K 5er and only lock out OD under these conditions.
There are a few threads in the towing forum that talk about this also. CLICK HERE
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Joined: Nov 2002
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From: Waynesboro Ga ...Haul custom Motorcycles
Re:Towing & Overdrive
I pull heavy at times 28000 GVW and always use OD...my tranny will downshift when its needed and unlock from OD (I have a Transgo shift kit).....at other times I watch my RPMs when its going outta the power band I just hit the OD button to unlock OD....your tranny is called a automatic for a reason it senses different conditions and shifts automatically
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From: Michigan
Re:Towing & Overdrive
I tow a 10.5k fifthwheel in OD most of the time, I watch the hills lock out my OD when the hill gets to steep. In 3rd I think the truck will climb the side of a house
Also I keep an eye on my tranny temp!!
KC
Also I keep an eye on my tranny temp!!KC
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Joined: Mar 2003
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From: Windsor, Colorado
Re:Towing & Overdrive
RTCRam,
Do you have the 48RE transmission? That was a mid-year release for the 03s. From what I have read, the 48RE is actually rated for towing in OD. Someone feel free to correct me if I am wrong.
Do you have the 48RE transmission? That was a mid-year release for the 03s. From what I have read, the 48RE is actually rated for towing in OD. Someone feel free to correct me if I am wrong.
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From: Houston, TX
Does anyone know of a site where I can find out which tranny I have...possibly by VIN number?
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From: SW Connecticut
I tow my 10.5K trailer in OD 90% of the time. I'll kick the OD off if climbing a long grade or the EGT's climb too high. If you have the HO motor you will have the 48RE. Look at the plate on the side of the motor. 305 HP = HO
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From: Houston, TX
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From: Udaho
I had the 2003 SO (hence "SOHappy") with the 47RE and frequently towed my 11k lbs toyhauler in the mountains and interstates. I found it best to use the OD lockout under 60mph, but on the flats on the interstate I'd turn it off so it would drop into 4th. I would run at 3100RPM when climbing mt. passes, we have a lot of long 7-10% grade hills around here and I had no problem keeping up with traffic (60-65mph). But on the flats, you should shoot for around 2000RPM and let it drop into OD. Of course, tires and rear-end gearing have an impact as well.
BTW, the only time I saw high tranny temps was in 1st-2nd gear on slow (<30mph) steep climbs (dirt roads) pulling the trailer. The torque converter slips under these conditions, so you have to be really careful not to toast it.
BTW, the only time I saw high tranny temps was in 1st-2nd gear on slow (<30mph) steep climbs (dirt roads) pulling the trailer. The torque converter slips under these conditions, so you have to be really careful not to toast it.
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