3.73 or 4.10?

[troverman]

I've towed 15,000lbs gooseneck with my 2500 6.4, 3.73 axle. The 8 speed transmission helps a lot. I'm operating in hilly / mountainous NH / VT. Up any significant hills, the pedal is to the floor and I may not be able to maintain the 55mph speed limit and the engine is screaming. That said, I'm not sure the 4.10 would really do any better. If your engine is wound all the way out going up a hill, a shorter axle ratio just means it will be screaming in a different gear, which might be slower. Perhaps 4.10 would take off from a stop better, but I'm actually pretty satisfied with how the 3.73 axle and 8 speed steps off from a stop.

I had an F-350 with the 6.2L gas V8 and the 6-speed transmission and 3.73 axle- this truck does better. Perhaps its because the Hemi makes a little more power and torque (I had the 2015 version of the 6.2L which made 405lb-ft, not the current 430), but I suspect it has more to do with the 8-speed and maybe because the Ford 6.2L was OHC and needed to really wind up to make power.

 

[snocam]

I've towed 15,000lbs gooseneck with my 2500 6.4, 3.73 axle. The 8 speed transmission helps a lot. I'm operating in hilly / mountainous NH / VT. Up any significant hills, the pedal is to the floor and I may not be able to maintain the 55mph speed limit and the engine is screaming. That said, I'm not sure the 4.10 would really do any better. If your engine is wound all the way out going up a hill, a shorter axle ratio just means it will be screaming in a different gear, which might be slower. Perhaps 4.10 would take off from a stop better, but I'm actually pretty satisfied with how the 3.73 axle and 8 speed steps off from a stop.

I had an F-350 with the 6.2L gas V8 and the 6-speed transmission and 3.73 axle- this truck does better. Perhaps its because the Hemi makes a little more power and torque (I had the 2015 version of the 6.2L which made 405lb-ft, not the current 430), but I suspect it has more to do with the 8-speed and maybe because the Ford 6.2L was OHC and needed to really wind up to make power.

I've owned 5 ford super duty trucks with the 6.2. I also had a 2022 f350 with the 7.3 and 4.30s. The 6.2 trucks were very reliable but not the hauler that my ram with the 6.4 and 3.73s is. The 2022 F350 with the 7.3 and 4.30s was a good tow rig, better than my Ram, but not by much. I really think the ZF 8sp in the Ram is a great transmission. The 10sp in the ford was clunky, jumped into gear when shifting from park to drive. But this thread is about axle ratios. Point is, 3.73 or 4.10, the 6.4 pulls really well for a gasser and I enjoy driving it more than the truck I traded for it.

 

[troverman]

I've owned 5 ford super duty trucks with the 6.2. I also had a 2022 f350 with the 7.3 and 4.30s. The 6.2 trucks were very reliable but not the hauler that my ram with the 6.4 and 3.73s is. The 2022 F350 with the 7.3 and 4.30s was a good tow rig, better than my Ram, but not by much. I really think the ZF 8sp in the Ram is a great transmission. The 10sp in the ford was clunky, jumped into gear when shifting from park to drive. But this thread is about axle ratios. Point is, 3.73 or 4.10, the 6.4 pulls really well for a gasser and I enjoy driving it more than the truck I traded for it.

I've owned two Super Duty trucks with the 6.2L, a 2012 and a 2015. The 6.4L RAM is far more responsive and the 8-speed is far smoother. The 7.3L Ford is a beast of an engine and likely putting out more than what is claimed based upon the TFL Ike Gauntlet results towing 16k and still beating the RAM towing 14.3k, as well as smoking the Chevy gas 6.6L. For everyday livability, the 6.4L with the 8-speed is awesome, better than the diesel and better than the Ford in my opinion. My biggest concern is how well the ZF8HP75 transmission will hold up over time while being worked within the rated limits of the 2500 truck. Keep in mind this is the same transmission found in the half-ton Hemi and EcoDiesel trucks, and it does not appear to be made any heavier duty for the 3/4 ton (or 1-ton gas) applications.

 

[aaronedmonton]

I've owned two Super Duty trucks with the 6.2L, a 2012 and a 2015. The 6.4L RAM is far more responsive and the 8-speed is far smoother. The 7.3L Ford is a beast of an engine and likely putting out more than what is claimed based upon the TFL Ike Gauntlet results towing 16k and still beating the RAM towing 14.3k, as well as smoking the Chevy gas 6.6L. For everyday livability, the 6.4L with the 8-speed is awesome, better than the diesel and better than the Ford in my opinion. My biggest concern is how well the ZF8HP75 transmission will hold up over time while being worked within the rated limits of the 2500 truck. Keep in mind this is the same transmission found in the half-ton Hemi and EcoDiesel trucks, and it does not appear to be made any heavier duty for the 3/4 ton (or 1-ton gas) applications.

I wouldn’t be concerned with the Transmission. That is the one thing that will probably last the longest. The engine seems to be more susceptible to issues.

 

[troverman]

I wouldn’t be concerned with the Transmission. That is the one thing that will probably last the longest. The engine seems to be more susceptible to issues.

I'm doing 3,000 mile oil changes and I expect the engine will run for 200k miles or more. Probably overkill, but I bet it solves the cam lobe wear problem. As for the transmission, I'm not so sure. The TRX, for example, uses the 8HP95 to handle the 700HP and 650lb-ft. Yes, that's substantially more than the 410/429 rating we have in the HD trucks, but the HD trucks will have so much more abuse in terms of heavy towing and snow plowing, and even empty weight. I am impressed with how cool the transmission seems to run even with a 10k trailer up hills, but it sure seems like the 8HP95 would have been better. Even then, Car & Driver reported the transmission started feeling loose or sloppy on their long-term TRX after 40k miles. I hope that never happens, the transmission is the best part of this truck.

 

[jsalbre]

I'm doing 3,000 mile oil changes and I expect the engine will run for 200k miles or more. Probably overkill, but I bet it solves the cam lobe wear problem. As for the transmission, I'm not so sure. The TRX, for example, uses the 8HP95 to handle the 700HP and 650lb-ft. Yes, that's substantially more than the 410/429 rating we have in the HD trucks, but the HD trucks will have so much more abuse in terms of heavy towing and snow plowing, and even empty weight. I am impressed with how cool the transmission seems to run even with a 10k trailer up hills, but it sure seems like the 8HP95 would have been better. Even then, Car & Driver reported the transmission started feeling loose or sloppy on their long-term TRX after 40k miles. I hope that never happens, the transmission is the best part of this truck.

3000 mile oil changes? Even the 8k recommended by the owners manual is earlier than needed most of the time per oil lab test results (though I just follow the computer’s recommendation).

 

[troverman]

Oil changes are cheap and easy. I'm not running the Penzoil Ultra-Platinum but rather Mobil 1 Euro formula.