Hello,

I'm looking for a tow pig with the V10 to tow a 5th wheel down to the coast maybe 6-10 times a year. It will not be my daily, I have a 2024 Lightning for that.

There is not a lot of aftermarket support for these engines, given the split-pin crank limits HP production, of course, there are the PI heads if you have a 99 down. And intakes/cat backs, plus tuning.

I figure these things have enough power to tow well as-is anyway, if they are geared properly to put the engine at an RPM at 65-70 where it is producing at least 80% of peak torque. I'm figuring when I find the clean, well cared for truck that I want, I will go ahead and change out the rear end gears.

Looking at the Dana/Spicer RPM calculator,
https://spicerparts.com/calculators/...rpm-calculator

A 4.88 gear, with a 31.5 inch (stock 17" tire) height, and a .71 final drive ratio, puts you at 64.94 MPH at 2400 RPMs, and 70.35MPH at 2600rpm. To me this seems about right to tow say 10K lbs with the V10, given the torque curve. Goals are to have good acceleration and to minimize downshifting on the freeway. I want to tow in the 65-70 range, probably biased more towards the 65 mph side of that, with the ability to speed up a little if the conditions demand it.

Given this will not be my daily, I don't have to make compromises around wanting reasonable RPM at 75-80 on the local toll roads.

Am I off here?

Some of the older towing charts, list gears up to 5.38 gears for the chassis cab Super Duty V10s. That seems a little extreme for highway use.

 

Yes 4.88 with a 31 inch tall tire is a little to much gear. Now 4.88 with a 35 inch tall tire is just about perfect. It works very well with 99-04 V10s with the 4R100 trans. I will recommend taking a look at 2012 - 2016 with the 6.2 with the 6R140. My son and I installed 4.56s in his 2013. When he keeps his foot out of it he gets a solid 12mpg vs my solid 10mpg on the toll roads.

 

My 2000 V10 DRW with 17" tires and 4.30 gears pulled out 16K 5th wheel all over the country without any problems. Would 4.88 have done a better job maybe but the rpms would have been a problem for me.

Denny

 

I have a 3/99/V10/auto,4x4 ,cc, 3.73 truck, with 285 tires. last good long haul was pulling a 24' cargo weighing an estimated 8000lbs across the US. My observations. #1, no way could I use O/D, unless going downhill only. #2 bucking a headwind of 20/30 mph Id estimate I was lucky to hit 55 and get 6mpg, good flat with no wind 8mpg. Truck is original and stock, free flowing exhaust stock muff, capiche?, no codes, runs smooth as can be, and empty gives 13 mpg. A few have said the truck has something wrong with it and should do way better, dunno??. Ive put 40K on it in 3 years and it never throws a code or skips a beat. Yeah, its a V10 but its only 415CI, what the heck you want is my thought. Now that dodge V10 I had, it ripped like cummins without the clatter....but of course it fell apart like a good dodge. LOL.