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
JIMNLIN wrote:.
Fords 3.31 vs 3.55 gears with the torqshift 10 speed @ 60 mph on 33" tires shows
7th gear = 164 rpm difference
8th gear = 125 " " ".
9th gear = 99 " "".
10th = 93 " ""
I doubt the 6.7 diesels big HP/torque will notice much difference.
Now the 7.3 gazzer may work a bit better with the 3.55 gears.
This is correct, either ratio will work great with the 6.7. You will not notice a 100-200 rpm difference.
Sure on paper the 3.55 will pull slightly better, but seat of the pants while driving they will feel the same.
