Ford super duty 3.31 rear end. Will it be a big mistake. ?
Pulling a 37 foot Cedar creek with a f350. Diesel. Would the 3.31 rear end work or should I get the 3.55?
Forum Discussion
TXiceman wrote:
Personally, I'd want a 3.73 axle for towing. The torque amplification is more easily handles in the axle than the transmission. Sure you have multiple gears and you can drop down to 4th or even 3rd gear to pull the grade.
Ken
When your cruising down the highway at 62 mph with a typical rv the torque output of the engine might be about 500 lbft in 10th gear with 3.55 gears vs 536 lbft with 3.31 gears. When you hit a hill and the rear wheel torque demand increases the 3.31 truck will drop to 9th, 8th or 7th before the 3.55. This is desirable. There is no point in putting high power (1000 lbft of torque) through the overdrive gears to speed the driveshaft up just to run that power through a high ratio rear end to slow it down again.
