Hi all, sorry for yet again another noise thread, but need some ideas.
Problem:
- Starting exactly at 75 mph a low hum which sounds like similar to a worn mud terrain starts coming from the front end. The noise is pretty quite, but it is felt slightly throughout the truck.
- It is consistent and gets slightly worse as you go faster (85 is about as fast I can go).
- Started after a long offroad trip last month. Noise does not seem to be getting worse with time.
- Shifting to neutral and coasting does not impact noise at all
- Accelerating or coasting does not impact noise
- Removal of front DC drive shaft fixed noise, but rebuilding it and re-installing it did not help. The noise is being caused by the front axle getting power.
What I've done, not any of this has changed the noise at all.
- Rotated tires
- Replaced front diff fluid
- Rebuilt front DC drive shaft with new U-joints and re-balanced at Drive Shaft specialty shop
- Topped of knuckles with grease
- Repacked front wheel bearings and checked preload. PS spindle does show a little bit of wear on bearing surface...
- Checked knuckle nuts
My thoughts on what it could be, but not sure if there are ways to easily check:
- Front spindle. I rebuilt the knuckles probably 10k ago and the space between the spindle and axle appear to be fully greased. The surface for where the outer bearing may be starting to wear, but hard to tell. Might just need to pull spindle off and check.
- Pinion bearing. 4.88 gears done by Zuk about 15k ago.
- Xfer case output bearing
Any input or things I can do to check components that are potential suspects? Thanks for your time.
Problem:
- Starting exactly at 75 mph a low hum which sounds like similar to a worn mud terrain starts coming from the front end. The noise is pretty quite, but it is felt slightly throughout the truck.
- It is consistent and gets slightly worse as you go faster (85 is about as fast I can go).
- Started after a long offroad trip last month. Noise does not seem to be getting worse with time.
- Shifting to neutral and coasting does not impact noise at all
- Accelerating or coasting does not impact noise
- Removal of front DC drive shaft fixed noise, but rebuilding it and re-installing it did not help. The noise is being caused by the front axle getting power.
What I've done, not any of this has changed the noise at all.
- Rotated tires
- Replaced front diff fluid
- Rebuilt front DC drive shaft with new U-joints and re-balanced at Drive Shaft specialty shop
- Topped of knuckles with grease
- Repacked front wheel bearings and checked preload. PS spindle does show a little bit of wear on bearing surface...
- Checked knuckle nuts
My thoughts on what it could be, but not sure if there are ways to easily check:
- Front spindle. I rebuilt the knuckles probably 10k ago and the space between the spindle and axle appear to be fully greased. The surface for where the outer bearing may be starting to wear, but hard to tell. Might just need to pull spindle off and check.
- Pinion bearing. 4.88 gears done by Zuk about 15k ago.
- Xfer case output bearing
Any input or things I can do to check components that are potential suspects? Thanks for your time.
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