How's the high end cruising with the 4.88s? Any issues with holding 80-85 mph?

How would the higher speeds compare with the 4.30 gearing? I also noticed the horsepower and torque are detuned almost 8% when the lower 4.88 gears are selected, think that would make much of difference?

Any help would be appreciated as I'm ordering my F450 in the next couple of days. Thanks!

 

A 6.4L with 4.88's runs almost 3,000 RPM at 80 mph. Regardless of gearing (4.30 or 4.88) the F-450 is speed limited to 81 mph.

I would say that unless you have a REALLY heavy trailer to pull that you choose the 4.30's and if you want a truck that can cruise at 80 mph + that you may want to reconsider the choice of a F-450.

 

Wow 80-85 Mph...I sure hope no one stops quick in front of you.

 

I thought only the 4.88's were limited to 81 mph??

 

seems like it would rev a little higher then 3000 rpms with the 488 gears at 80 mph.

 

Nope mine is actually about 2850 at 80.

 

Don't worry I won't be doing that through downtown. There are areas in the West like I5 in CA and I80 through Nevada and Wyoming where you'll get passed like you're dragging an anchor if you're doing 80.

Thanks for the info, guys. I'm leaning towards the 4.30s as most of what I tow is under 20k# and beyond that I'll take the Freightliner.

 

Does anyone have a definitive answer for this?

 

the 450 is limited to 81MPH. Due to the tires.

 

Yep what Percy said............Tried it, got maybe got 83-84 on the flat but no more. Maybe more if your going down a big hill!

 

try turning the key

 

C'mon Percy the key was on, I know that cause I can hear the radio!

 

try neutral

 

Kinda seems like a good argument for going with the 4.88 extra tow package then.

I saw in the brochure that a 4.88 equipped truck has lower horsepower and torque, about 8%. Wonder if that makes a difference that can be felt in the seat of your pants.

Can anyone tell me the RPMs on their 4.30 geared F450 is at 80MPH or make a comparison at any highway speed to the 4.88s?

 

What I was wondering is if you're not pushing the GVWR with the 450 too much, if the difference in power is worth the .5 in gearing? Say you tow in the 18-20k lb range, I would love to see some 0-60 times loaded up between the 4.88's and the 4.30's. Someone hook up to 20k lbs and throw a g-tech in there lol.