TXJFrosty
Member
truck - 2014 Ford F250 Super Duty 6.2 3.5" lift 37" tires
I recently had the gears changed from factory 3.73's to Yukon 4.88's. Had this done by a reputable shop that does all the gear swaps for a local offroad shop.
Drives much better, shifts better as well... also no longer hunts around. Except - once I get over 50 mph it starts to develop a loud rumbly noise in the cab, and by 55 - 60 mph it's much louder. Once I get to, say 60 mph, and let off the gas to coast, the noise all but goes away. There is also a slight, best way to describe it is, rumbly feeling that accompanies the sound. The sound is not a whine, but a deeper sounding rumble maybe even a growl.
None of the sound is tire related road noise however. If there was an issue with gear backlash and pinion depth, would that be constant all speeds, rather then the 50+ mph issue I am experiencing?
What I am experiencing happens at 50+ mph and gets worse around 60mph+, and seems to been a little less if I put it in TOW mode (button on the shifter). All the while the drive quality is great (acceleration, shifting etc), even at 50+ (other than the deep rumble sound and slight rumble from under the cab at hiway speed). Could it be something else, like tranny or drive shaft? Could the lower gears be amplifying a problem that I was not really noticing before?
The truck has 78k miles, and nothing has been replaced until the gear swap last week.
It always made a funky rumble when I would take my foot off the gas... say going 55mph, take foot off the gas, it would make a slight rumbly sound and vibration then clear up in a second or two.
I'm headed back to the shop this afternoon to have them drive with me to hear/feel what is going on.
Thoughts?
I recently had the gears changed from factory 3.73's to Yukon 4.88's. Had this done by a reputable shop that does all the gear swaps for a local offroad shop.
Drives much better, shifts better as well... also no longer hunts around. Except - once I get over 50 mph it starts to develop a loud rumbly noise in the cab, and by 55 - 60 mph it's much louder. Once I get to, say 60 mph, and let off the gas to coast, the noise all but goes away. There is also a slight, best way to describe it is, rumbly feeling that accompanies the sound. The sound is not a whine, but a deeper sounding rumble maybe even a growl.
None of the sound is tire related road noise however. If there was an issue with gear backlash and pinion depth, would that be constant all speeds, rather then the 50+ mph issue I am experiencing?
What I am experiencing happens at 50+ mph and gets worse around 60mph+, and seems to been a little less if I put it in TOW mode (button on the shifter). All the while the drive quality is great (acceleration, shifting etc), even at 50+ (other than the deep rumble sound and slight rumble from under the cab at hiway speed). Could it be something else, like tranny or drive shaft? Could the lower gears be amplifying a problem that I was not really noticing before?
The truck has 78k miles, and nothing has been replaced until the gear swap last week.
It always made a funky rumble when I would take my foot off the gas... say going 55mph, take foot off the gas, it would make a slight rumbly sound and vibration then clear up in a second or two.
I'm headed back to the shop this afternoon to have them drive with me to hear/feel what is going on.
Thoughts?
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