Frank, I'm not sure why you are unable to tow that weight in OD. I'm towing a 35 1/2ft fifthwheel that scales (certified scales) at 12,500 lbs, with full fresh water tank and loaded for a weekend. My '99 F350 has the V10, 4R100 auto trans. It originally had the 3.73 rear gears but when we traded for this fiver I swapped in the 4.10 gears. 4.10 is not a factory option for the V10 although it's available for the 5.4 and psd. However, 4.30 gears won't fit this pumpkin so the 4.10 it is. I tow in OD as a matter of course. It does drop out of OD on many hills of any size. That's what it's supposed to do to put the engine into a stronger power band. However, if you are in a series of hills where it will frequently shift in and out of OD, then it's a good idea to manually take it out of OD. The reason is all that shifting generates heat, which is hard on the transmission. The prior FW was 11,100 lbs and the V10/3.73 did a great job of towing it, in OD. If you're more comfortable not using OD, then towing at 3000 rpm is not going to hurt that truck at all, in my opinion. Good luck.

steve reigle

 

Sounds like a nice rig, Homebrew! Your GCW is about 4000lbs above mine yet.
steve reigle

 

I live in Wyoming and tow all over the rockies with my 2002 cc v10 4x4. I have pulled some steep grades with my v10 screamin away. I have seen it at 4200 rpm for several minutes on some steep grades. I think that was in second gear doing about 45mph or so.

I pull a 28' toy hauler camper. Loaded I am pushing about 11000 pounds and the V10 does pretty good. I have been thinking of trading up in the next year or so to a diesel.

Oh and I have the 3.73 axle also.

Bat

 

Interesing, I have a 99 Fleetwood Bounder 35 foot pulling a 94 Jeep Cherokee. I scaled it out a Flying J, full of water and empty sewage tanks with 80 gallons of gasoline and full Propane, evey bay loaded underneath. 29,000. I travel a lot in this rig and 9-10 miles per gallon is not uncommon. I have pulled 11,000 ft passes and been in 25 below zero temperatures. Never a problem. RPM wise, 70 mph is 2900 RPM. I have never reved over 4500. This engine works like a champ with 87 oct. The noise facter is minimal. No vibration. I do have a Banks. That made it a little noiser but I like the growl.

I like this info on the GV....thanks




>What a bunch of light weights. I am running a 32'
>motorhome, pulling a 97 Mazda PU with a combined weight of
>23,000 lbs. My rear gearing is 5.38 although tire size in
>19". Upon buying this unit last summer, I had a Gear
>Vendors auxillary transmission installed. This gives me the
>ability to split the gears. When using the GV, I disengage
>the Ford OD and use the OD of the GV. 3000 rpm gives me 64
>mph which is just fine with me. Last month I averaged 7.1
>mpg over 3,000 miles and all of this with an intermitent MAF
>sensor. It is in the shop at this time getting the sensor
>replaced. Gear Vendors recomends keeping the RPM between
>3000 and 3500, using these rpm's as shift points. Letting
>the Ford transmission do it's own thing is scary, have seen
>4,500 rpm on the freeway maintaing 70 mph. It might do that
>for a long time, but in a motorhome with the engine beside
>you, it is awfully busy sounding.
>
>