tchdodg

I have a 2000 Dodge 2500 4x4 with an automatic tranny. What are the rules for towing with OD. My other vehicle was a 5sp. What I did with it was when my rpm's dropped below 2000 I shifted into 4th. This worked, but the truck also had 3.55 gears in the rear. Anyway, my Dodge has 4.10's and it seems like it wants to pull in OD. Most of my loads are in the 4500 to 6500 pound range and I can maintain 1900 to 2100 rpms in OD. Is this OK? Am I going to burn up my tranny? All thoughts are appreciated.

P.J

I have towed fairly heavy (9000 lbs.) in OD. I like to see my RPM's above 1550 or so. I have a stock truck, so I it starts to wimper a little if I tow heavy in OD without watching the RPM's Out of OD I can run abour 60 mph @2000 RPMS, okay for short distances, but on flat highway I kick it up to about 70-72 and feel safe in OD.
One thing is for certian, if you let it hunt and/or downshift while towing in OD you will burn thigs up for sure.

Maybe someone who knows more specifics will add to this.

On Edit: I don't have 4:10's, ignore my RPM and speeds,

JD730

I tow heavy (12,000 lbs. trailer empty is 5000lbs.) with 3.55 gears. I can cruise 65 to 70 mph at 1700-1800 rpms on flat ground, but I cannot lay the loud pedal down or it will slip in OD(looks like the rebuilder will be doing it again). Any kind of hills require me to do 75mph and stay above 2000 rpms. Otherwise down into 3rd it goes.

With 4.10's it should be alittle easier on the trans. I'm slipping OD with a rebuilt trans that supposedly been built to take it.

Mine will not hunt as I don't have any PCM to control Lockup functions, I use a switch on the dash.

Trans temp gauge would be a real good idea to have too.

I'm sure I forgot something, someone else should have some good input too.

hardyhindle

I pull 8000lbs with mine, and just leave it in OD. It seems to do a good job at picking what gear it needs to be in, and 98% of the time, it just stays in OD. They have a safety feature built in (I don't know what year it started in) that when the tranny builds too much heat in OD, it will dump a gear for a while till it cools down. There is a good 5 mile grade near my place, and my truck has used that feature more than once in the heat of the summer..

45000km and I haven't wrecked it yet... almost halfway to the end of warrenty though...

J BODY

Safety feature?!? Is that what you call it when you overheat your engine and it automatically de-fuels so it won't melt? That is a "your lugging this trans and the fluid is getting super overheated because you didn't shift down to keep your rpms up at a decent pulling rpm" feature.

tchdodg, what you're doing is just fine, but if you're rpm's cannot be maintained, slow down and dis engage the OD. You might end up pulling the rest of the grade at 45-50 mph, but the r's will be in a "happy spot" if you can maintain that 2100 + rpm range.

John Rodriguez

I've towed 10klb in OD at 55mph (1,500rpm) and had no problems pulling grades except lots of barking after cresting the hill, but that's due to my mods. I'm on my stock tranny pushing over 500whp on big tires, and I tow. All I can say is put Dextron in the tranny instead of ATF+4, it slips less. I would hit 220 degrees on my pan temp just driving normally at less than 5psi of boost on 37" tires no trailer. When I went to Dextron I haven't had it over 180, even towing (and racing)

yamroamer

My 2002 has 4.10s fitted and I was thinking of changing to 3.55s for better mileage when solo.When towing a caravan in the UK the speed limit is 60mph and when towing in Spain its 50.Would it be better to stick with the 4.10s and use higher revs,does this put less strain on the o/d?

DanTana

The best advice I can give you is listen to your engine. Feel your truck. Mine will vibrate a little at lower rpms if I lay into it to hard. If ever in doubt downshift with the tow/haul button. After a while you can learn to control the rigs entire feel by the push of a button. 'bout like sex!!

DennisB

My truck is a 97 - 2500HD. I had a transmission temp. gauge installed and the seding unit is located in the transmission line not the pan. I've just purchased a new 5R. Gross net weight is 8250. I took the truck and trailer to the scales and had them weighed. 15,000lbs. That included a full tank of diesel, me and my wife. The trailer was empty. The truck manual recommends a GCVWR of 16000 lbs. So I can load about 1000lbs of stuff for a trip.

My question is regarding the best driving technique so as not to screw up the automatic transmission. Should I be driving not using OD? Some say it's OK to use OD on flat runs. How does RPM play into this? Any guidance would be appreciated.

John Faughn

Trans. temp gauge.

MnTom

You can tow in O/D all day long without hurting a thing. PERIOD. Where you run into problems is when you allow the engine to lug or the tranny to hunt. Just listen to the engine, pay attention to the tach, pyro AND tranny temp gauge and you will be OK.
Tom

flippinfred

What MnTom said......except....if you decide to start bombing. I put 43k on
our '01 with maybe 15k of that pulling our 5ver. Once I added the Banks "Git
Kit" I puked our tranny in one day.

Watch your rpms, use 1600 or more as a minimum and you'll be ok. Let the
truck tell you whats' comfortable; if it won't respond to peddle...downshift.