Whats the best towing rpm for power /economy. Right now
I have LT265/75R16 tires that put me at 1900 rpm @65 mph.
I wanted to go up to LT285/75R16 tires to fill up my wheel wells
more, but I think my rpms would drop to the 1600-1800 range
and I don't want to lug the engine. Trailer weighs 6500# , used
once a month for camping with the family.

 

I have a trailer that's roughly the same weight as yours. I try to keep the rpm over 1600, and over 2,000 when I want power. You've got an EGT gauge, so you probably have a better feel for what the lower rpms do to EGT when you're towing than I do.

 

I like to pull at 2,100 or 2,200 Lots of power and your rocking right along with a 3.55 rear end.....

 

From my experience, and others here as well, the best towing RPMs are between 2000 and 2200. With my 4:10s it puts me between 61 and 67 mph, right where I like to be with the fiver.

 

i haul the same load....and i try to stay over 2k. if i will be lower then that for a while i will lock out overdrive....a little diesel is cheaper then engine and tranmission wear...and honestly it makes very little difference in mileage IMO

 

Hi Dieselcamper........I asked this question a few months ago and really opened up a can of worms unintentionally! Got some really great info though! Check it out at

https://www.dieseltruckresource.com/...threadid=53783

Hope this link works. Lots of good stuff there.

Steve

 

I tow in 4th gear only for fear of the 5th gear nut and my RPM's are around 2200-2300 at 60 mph. The higher RPM's make my exhaust brake work better to.

 

With the 4.10's, 70 MPH puts me at 2350 RPM in 6th gear. One advantage of running around 2350 RPM is that I'm slightly on the top side of the torque curve, so when I hit a grade any decrease in road/engine speed results in an increase in torque. In actuality, though, I don't have any problem holding 70 MPH up 6% grades in 6th gear on the Interstate with our 16K GVWR 5th wheel in tow.

Rusty