Towing in OD with NV4500

[Kollin Syverson]

How many of you tow in 5th gear (overdrive), and if so have you had any problems such as overheating the tranny, etc.

[Showgood1]

If you look in your owners manuel I don't think they recomend pulling OD. At least they didn't in '93. I did it with a light load boat etc. but I wouldn't pull anything real heavy with it. I don't know much about them overheating but the limit of the nv4500 in fifth gear is a matter of design. The OD gear is added almost as an after thought. It runs on a much smaller gear and shaft assembly and cannot handle the weight of a heavy trailer. We have had several of our 3500HD's at work fail. The truck I had with one only had 47k on it when I got rid of it but I never had any trouble the the tranny. My friend kept his untill the 100k warenty ran out also without problems.

[James Hewett]

Yes, I do tow in O.D., but I keep an eye on the RPM's, if you want to get rolling over 55mph and want to go faster, you almost have to and you can make better time going up the next hill, if you roll down one hill about 65 to 70,that's when you run OD I even have hit the 75mph mark, of coarse you have to build yourself up to it and have confidence in your trailer, my 5ver trailer rides very nice and stable.
If you keep the RPM's up above 2000,and the headwind doesn't hold you back , you should not get the tranny hot. Once you see the speed dropping, you must take it out of OD until your moving fast again.
One thing that makes my trans. run hotter is being in bumper to bumper traffic.At them times I wish I had an electric fan aimed at the ATF cooler.

[DmaxProf]

I tow my 12,000 lb. 5th wheel in OD all the time unless I am pulling some steep grades or a series of constant small hills. I also always tow with Tow/Haul on. I have not had any heating problems at all, even driving through Kansas and half of Colorado in the heat of July.

[Inspector]

I pulled a 36ft king of the road all over the place with an nv4500 and never had a minutes problem with in 5th gear. It was in a 93 3500. My trailer sitting at the curb with nothing in it but water and propane will weigh about 12000lbs. Road loaded near 14000lbs. I used 5th gear and 5th over on the gearvendor all the time and it would run with the big boys and did it for about 40000 miles. Its all about feel and I could run back and forth between the gears according to what was needed. No one is going to just let his truck lug around all day in its highest gear. The trans is quite capable of towing in 5th gear. Watch your temps and pressures and tow on.
Denny

[Turbo Al]

Guys the NV4500 is a STANDARD trans not an auto.
I have towed quite a bit in OD with the New Venture 4500 and at 175,000 miles it is still as good as new. I do average around the 6,000 lb mark (trailer and cargo).
I do also have a temp sensor in it and keep the trans below 200.
Like Denny said -- don't lug it.
Al