Driveline noise under load

[eclouston]

Hello I have a grinding noise that happens when the care is under load. Its most noticable under minor load weater it be on the throttle or slowing the car with the motor it is there. I have read similar threds about noise off the throttle in the trans like on a down shift. Mine is more of a constant under any kind of engine load. I changed the trans fluid, diff fluid and transfer case fluid, From what I have read .It seems like it could be the axel carrier berrings does anyone have any other sugestions.

Eric

 

[eclouston]

Just to make my discription more clear the noise seems to be comming from the front to mid of the car not rear and by grinding I dont mean like when you miss a shift its more like scraping a tin can on a rusty pole noise but its a constant. Its not super loud but loud enough to be super anoying.

 

[Nanan]

Bump = bad, if you want to add more information then use the edit button.

When your carrier bearings die you will hear a screaching sound that changes with speed. When most talk of carrier bearings going out it is not the actual bearing but the rubber bushing that mounts the bearing. The rubber gets old and soft which lets the driveshaft wander around a bit more then it should which causes vibrations something fierce.

Grinding noise is generally something to do with gears, in AWD cars it is usually the Transfer Case taking a crap. Grab the yoke near the transfercase and give it a good twist back and forth, if it moves much more then 2-3deg then it is likely that the gears have worn down beyond the critical level. This is usually a gradual thing so you dont really notice it till it gets really bad.

What did the oil look like that came out of the transfercase? How much came out? What did you put back in? You should get over 1 qt. The oil should be clear to a light brown. Mitsu suggests using 80+wt shockproof oil, I suggest 95wt mobil 1 gear oil and a bit of anti-foam additive from lucas oil.

 

[eclouston]

The oil looked like it had 117k miles on it and was more black and stinky than brown and I put syncromesh in to replace it . This didnt change the noise what so ever . If I pull the car out of gear or press the clutch in the noise goes away. I will check for play in the shaft tonight . The car still has the stock clutch could the thrust bearing or through out bearing cause this noise? Thank you for your quick reply.


Eric

 

[GVR4592]

The throwout bearing can make the noise you are describing but it usually goes away when you depress the clutch pedal.