MUDWHISTLE
Diesel Lover
3-StarJ.R. said:
6203-rsj is the same bearing with metal dust seals from napa if you prefer
What's this pulsating sound?
- Thread starter hheynow
- Start date
6203-rsj is the same bearing with metal dust seals from napa if you prefer
3-StarJ.R.
53 year old kid.....
hheynow said:
Very easy to change out the bearing, just find a socket or piece of pipe that is the diameter of the bearing and pop it out. You want to look @ the original bearing seated in the pulley so that you get the new one seated the same, that keeps the belt tracking on the pulley at the same location...hope it solves your pulsating noise problem, I hate trying to track down weird noises......
In Edit: heynow forgot to mention, the star drive bit is a number 45 if I remember correctly, but it seems loose in the head of the bolt. Just be careful about rounding it out....
ThreeJacks: Man you got good taste in color and configuration of trucks!!
Last edited:
threejacks
Full Access Member
3-StarJ.R. said:Very easy to change out the bearing, just find a socket or piece of pipe that is the diameter of the bearing and pop it out. You want to look @ the original bearing seated in the pulley so that you get the new one seated the same, that keeps the belt tracking on the pulley at the same location...hope it solves your pulsating noise problem, I hate trying to track down weird noises......
In Edit: heynow forgot to mention, the star drive bit is a number 45 if I remember correctly, but it seems loose in the head of the bolt. Just be careful about rounding it out....
ThreeJacks: Man you got good taste in color and configuration of trucks!!
I have new bearings in idler, I don't think that's the problem.
3-Star JR. Thanks for the truck comments. I had been noticing yours too. You do have a few more goodies on yours.
JOAT
I Found Nemo!
Thinking a bit more about this. Since it is an oscillating sound it is likely multiple devices that reach certain frequencys that cause an audible resonation (bad description, sorry). Example I gave Richard earlier was a guitar with one string out of tune. There are certain points where the vibrations overlap that sound louder.
I may still be a single source causing the sound, but usually needs another sound to play off of to get the pulsing effect.
SInce it happens at a certain road speed it must be partly drivetrain related, otherwise you should hear it when reving the engine to the same RPM. Try a different gear if possible at that speed, or throw it into neutral above the speed (as whatabudro said) and see if it still comes back as the truck slows back to that speed with the engine idling. May help to narrow it down some.
Often if tires are a contributing factor changing pressure will have some effect on the sound or related speed.
Assuming it's not getting worse, it may be easier to avoid that speed than to track it down...
I may still be a single source causing the sound, but usually needs another sound to play off of to get the pulsing effect.
SInce it happens at a certain road speed it must be partly drivetrain related, otherwise you should hear it when reving the engine to the same RPM. Try a different gear if possible at that speed, or throw it into neutral above the speed (as whatabudro said) and see if it still comes back as the truck slows back to that speed with the engine idling. May help to narrow it down some.
Often if tires are a contributing factor changing pressure will have some effect on the sound or related speed.
Assuming it's not getting worse, it may be easier to avoid that speed than to track it down...
hheynow
Señor Aceite de Soja
Replaced the idler pulley bearing and put on a new serp belt but the noise is still there. 
I hear what JOAT said but if that was the case why didn't I hear the sound before? Could my water pump be making that Wah...Wah...Wah sound? It doesn't weep coolant and coolant temps are low/normal. The sound is audible at various speeds contrary to only hearing it at 65 mph. As I said before, the truck runs great. Fan clutch is tight and dry.
-popcorn
I hear what JOAT said but if that was the case why didn't I hear the sound before? Could my water pump be making that Wah...Wah...Wah sound? It doesn't weep coolant and coolant temps are low/normal. The sound is audible at various speeds contrary to only hearing it at 65 mph. As I said before, the truck runs great. Fan clutch is tight and dry.-popcorn
threejacks
Full Access Member
I was on a good smooth straight section of highway today and tried to check out my sound a little more. It would make the sound from 50+ to 65 mph. I let off accelator and put tranny in neutral and while coasting from 65 down noise was not there. Tried it again and got back up to speed and put in neutral and tried to hold rpm's from 1800 to 2500 and no sound. Put tranny back into Drive/OD and could here sound once more. With a lite touch on accelerator I can accually feel slight HMMMM or slight vibration on the bottom of my foot. Could only make the sound with tranny engaged and holding steady acceleration.
MUDWHISTLE
Diesel Lover
Turbo surging? I can hear mine making a surging sound if I'm riding on the passenger side (can't hear well in the right ear) that would explain why it has to be in gear under somewhat of a load, does it do it if your pulling a load (creating more boost at the same engine speed?) Just a thought
threejacks
Full Access Member
I don't detect this noise when under load. When I hear it most is steady and smooth, stereo off, smooth level road, cruise control on(steady rpm). Everything has to be very quiet, it is not very loud but concerning.
hheynow
Señor Aceite de Soja
threejacks said:
Ditto here. If it's tranny related I'm under warranty. I had mine rebuilt two months ago. To me it sounds like a surging sound or a weak pump impeller. This is a stretch but perhaps my coolant is due for a draining? Then I thought it might be related to my transfer case not being fully disengaged, but if the problem is the same as yours, isn't your dually 2WD? I wish I had a scanner and could scan it while the noise is audible.
