Is your Ram towing as Good as it should?
Or does it not have the power it should have. It seems that Ram is putting the WRONG gear in their trucks. Seems if you ordered a 3.55.1 axle. You could have got a 3.21.1 axle. AND they won't even o...
Forum Discussion
Terryallan wrote:Grit dog wrote:
Sucks if the owners didn't get what they ordered but with an 8 speed trans, it's not hard to pick a gear that has the same effective final drive ratio.
Ah, but what about 1st. It's going to be much higher too.
We can debate for days, but here are some facts:
- 8 speed + 3.21 equals the old 545RFE/65RE + 5.029 gears
- Old 545RFE came with 3.92 gears at max, which is rated to tow 10,000 lbs
- 8 speed + 3.21 can easily out-tow ANY 545/65 gear combo
- 10,000 lbs is above the capacity rating for 8 speed + 3.55 gears
- 8 speed has a higher torque capacity than the 545/65 ("70" rating vs "45/50" rating)
- Therefore, any engineer can conclude no damage can occur from towing with the 8 speed + 3.21 combo, at or below the spec for 3.55 gears.
BTW, the max stress on a transmission is ONLY dependent on the torque input of the engine, NOT the output gear ratio (diff). The diff ratio only affects torque experienced by the axle tube, ring gear, drive shaft / hub, wheel and tire.
But that's a 10 page argument in itself which I've done here and on Ramforumz. If anyone wants to debate that I'll draw a free body diagram of the torque path from engine to rear tire.
