rear diff?????

[lowlows18]

on my 97 Tahoe 4x4...the rear diff is making like a humming noise...the faster i go the louder it is...if im doing like 50+ and im just barley pressing the gas its not that loud but if i press the gas harder it makes it louder...the noise is coming from the middle rear......what could it be..rear diff, drive shaft, ...any ideas???.... i don't know if it makes a different or not but i have 22's on the truck...i even put the stock rims on thinking it was my rims or something but it didn't make a difference ....thanks in advance

 

[blueflamed03]

u joints, ring and pinion, etc

have it checked!

 

[ravingmadman]

You probably have a GM 10 bolt rear end, which means you can do a lot of the checking yourself, for less than $10. You need to go to Schucks, get a new rear diff gasket, some 80-90 gear oil, and a drip pan. Unscrew the bolts holding the diff cover on, pry it off, get oil everywhere, look at the oil. If the oil is really sparkly, that's metal. That's bad. If you see chunks of gear teeth, that's bad. I can't remember what the tolerance is off the top of my head, and it will depend on the rear end you've got, but you can slip a gap meter (another cheap tool) between the gears in there, and check the gap.
Throw the new gasket on, bolt the cover back on, and fill it as full as you can with oil.

How to check a u-joint:
http://www.tahoeyukonforum.com/forum/showthread.php?t=1913

How to change a u-joint:
http://www.tahoeyukonforum.com/forum/showthread.php?t=1930

 

[bowtiefreak]

Yup, drive shaft u joints or ring and pinion getting ready to die. Check it before you are left sitting.

 

[hapyspaz]

While you have taken your 22's off, they have already done their job and aided in the damage. You need to get severe duty u-joints, and stronger gears if they are damaged.

While you are at it, you may want to start thinking about getting an oversized rotor/brake kit.

 

[Superman84]

Sound like one of the bearings in the rear end probly the pinion bearing. does it vibrate or just make a whine noise