Whining noise when accelerating - '05 Ram 3.7l
 

2005 Dodge Ram 1500 3.7l V6 rwd with approx. ~160,000 miles

My truck has starting making a "whining" noise whenever I am accelerating. The pitch and volume change the faster I go and I first notice it around 20 mph. It kind of sounds like a supercharger. The noise reverberates through the cab so I've had trouble telling whether the sound originates from the front end or rear.

I checked the serpentine belt first but that looked good. I put some WD-40 on the belt but that made no difference. Then I took the belt off and turned all of the pulleys by hand but they all checked out. After that I decided to look in the rear end and noticed my differential fluid had gotten very low. Oddly I couldn't find any source of the leak. I cleaned the differential and put new fluid in it but that had no effect on the whining sound.

I'm stumped. So far the noise has not affected performance whatsoever, it is just annoying. Does anyone have any ideas? Any 3.7 experts on CF? :dunno:

42RLE?
Check the fluid level & condition the pump could be failing.

does the pitch rise and fall with rpm or road speed? if road speed check driveline, if rpm check engine/trans. rear dif fluid being low is suspect. if it ran low for awhile the damage may be done already.

Correct. The fluid looks good.

The pitch changes with road speed. I'll take a look at the driveline. I was concerned about the diff too. When I cleaned it out I didn't notice any wear, thankfully. But I'm still new to all of this so I easily could have missed it. :sweatdrop:


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