I have a 2000 psd dually with a 6 speed stick, big pickup camper and tow a horsetrailer maxing around 9,000 lbs. The truck does a great job towing but if I tow in 5th, she goes to about 58 mph and then the rpms get a little high -- around 2800, engine works harder, mileage isn't good either. Towing on the flat in overdrive seems like the engine uses little effort-- in the low 60s mph and rpms close to 2000. When I drove the old 460 cu. in. gasser the word was "don't tow in overdrive", you'll ruin the tranny even if it is a manual. What is the word these days? The owner's manual does not state that overdrive should not be used for towing....

Thanks in advance for the advice-- rather hear it now than experience it later!

Henry

 

I don't think I would tow anything real heavy in overdrive.You can tell by the way the engine is handling the load,if it seems like it is working hard when pulling the load in overdrive than I would not use it.

 

On the flat you're probably ok in OD if the speed warrants it, but you may just have to drop down the speed and run hills in 5th. That's kind-of what comes with towing a whole lot of weight. That's what I do with my auto tranny - once it kicks out of over drive for a hill I lock OD out and just plug away at that speed until the top. I'm not real familiar with towing with a manual tranny so hope you get some better info - just my $.02!

 

Unless you are really bogging down the engine keep it in OD. I have a 5 speed and tow in OD and only take it out when I feel that it is struggling. Usually this is on moderate hills when towing. Small hills even when fully loaded it stays in OD and doesn't lose any speed.

 

I tow in OD all the time without any problems so far. My 5th wheel weighs around 11k or 12k depending on what toys I bring. I do the tranny service every 30k though. I do turn off OD on hills though. Basically my rule of thumb is to turn off OD going up any hill that is steep enough to warrant engine braking if I was going down the other direction. (not sure if that makes sense or not...) I recommend spending 3 or 4 hundred bucks and pick up a set of nice guages so you can watch important things like tranny fluid temp and boost. EGT are nice to know if you have any mods.

happy motoring!

 

What's the rule for a 97 7.3 automatic with O/D?

 

I'am not sure about an automatic Biesel Diesel because I own a 94.5 7.3 manual and she don't have much trouble hauling what I haul .But like I said before you can usually tell by the way the engine is responding to the load if it sems to be bogging down bad than shift it out of overdrive.

 

Chavez,

Hey since you live in Tucson I know your tranny will run close to what mine does. I haven't pulled my toyhauler fifthwheel in the summer yet. What temp does your tranny usually get to? Do you have an after market cooler on it? I have a larger trans pan and during the winter towing it to utah from phx it never got above 150. So I was just curious about the summer months?

Fire Rooster

 

Guys,
Have had my guages about 3 months now and the temp seems to run about 140 degrees on my commuter run of 15 miles. When I'm towing my tractor and toys it goes to 160 as long as I am running 60-70 mph. I do not come out of OD unless my motor is lugging, try to keep that from happening if I can. I was towing a fertilizer spreader last week (about 4000 lbs) and could not go over 35 mph, tranny temp went up to 190 after about 20 miles. Not much air flowing over the cooler I guess (still running stock cooler). I'm anxious to see what temps do over the summer!!! Paul

 

If you are worried about your trans and you have an auto trans for you PSD, Banks offers a trans module that regulates the ammount of fluid being used for shifting points and what have you. I'm sure there are more companies out there with similar stuff, but I hear it helps the auto trans out alot under a heavy load. Derek

 

BieselDiesel asked:
When I tow with my '95 automatic, I tow in OD until the tranny kicks down, then lock out overdrive until I'm over the hill.
ReserectedSD said:
A sonnax valve and tricumulator springs added to your tranny would do the same thing. The valve increases line pressure throughout the valve body, and the springs help make the shifts happen quicker and firmer, keeping heat down. I'd also recommend a larger tranny cooler. The stock tranny cooler, at least in the pre-Superduties, was only rated at 10000lb gvw. Once you start towing, you're overworking the tranny cooler. I put on a Tru-Cool tranny cooler, rated at 24000lb gvw, and even towing a 28' travel trailer over the Cascades in August, my tranny only got to 165 degrees once, while coming over the pass at 70mph. The rest of the time, the needle was at 155.