metallic grinding noise in rear end

[swynx]

so my moms car (1985 toyota celica) developed a problem. she was driving it and started hearing a grinding sound, it got worse over 3 days, then the rear end just locked up. (its rear wheel drive, with independant on all 4), they tore the pumpkin off, drained the fluid and filled it back up. it drove again with a grinding sound.

2 days later it locked up again, so she parked it, i came over to diagnose it (her boyfriend is mechanically challenged), i got in it rolled backwards, i started it and drove it forward to see if it would move forward, then drove it back to her house (1 mile from her friends, where it was parked) about half way there the sound started, the further i drove the worse it got.

i noticed i could only hear it when i let off the gas pedal, it wasnt rpm dependant, and didnt get worse with load. ive been told there were no metal shavings in the fluid, nor did it smell funny. im assuming bearing failure. any input?

a new rear end is 150$ - 400$.

 

[adsm08]

Sounds like it is time for a rebuild. The play caused by bearing failure can often lead to undesirable wear of the gears.

 

[Spott]

Are you sure that the rear end was the part that locked up, and not the transmission?

You might unhook the driveshaft and double check where the grinding is coming from.

Clean fluid with grinding/locking just doesn't jive.

Also, the fact that the problem returned immediately after being checked by the pro's kinda sounds like either they didn't try very hard, or they weren't looking at the actual problem.

 

[swynx]

Are you sure that the rear end was the part that locked up, and not the transmission?

You might unhook the driveshaft and double check where the grinding is coming from.

Clean fluid with grinding/locking just doesn't jive.

Also, the fact that the problem returned immediately after being checked by the pro's kinda sounds like either they didn't try very hard, or they weren't looking at the actual problem.

it could be the transmission i mean its got 300k miles on it. but it sounds like its coming from behind.

also if it was the transmission wouldnt it be gear dependant? (unless it was a bearing) i mean it seems to get worse when you push on the breaks instead of the gas.

i did the clutch on the car about 4 months ago and the fluid in the transmission showed no signs of anything bad. i havent seen the rear end locked up, that is just what i was told.

perhaps i should go drive it around till it locks up, if i throw it in neutral and try to tow it, if the tires lock up it should be the rear end.

 

[black_demon69]

get car on jack stands and see if sound starts with it in gear and wheels spinning.

 

[bmerr98]

get car on jack stands and see if sound starts with it in gear and wheels spinning.

What he said. The "drive it until it completely fails" method can do more harm than good and leave you needing a ride home. Slow down and do some diagnosing. Wheels up, driveline disconnected, spin one side then the other, stuff like that. With 300k on it, it'd be easy to find yourself spending more than it's worth to fix it. Of course, we all own Rangers and have probably long since crossed THAT line!

 

[AgPete139]

I would check the rear drum brakes.

You stated that the wheels completely lock up, are independent from RPM's, gets worse as you drive (longer), and you only hear it when you let off the gas pedal. Transmission fluid looks clean.

Drum brakes are often overlooked than discs because they are trickier to some people.

Lift up the rear, take the wheels off, and then take the drums off. Sometimes the anchor, return springs, or brake shoes get worn and parts can fall off it doesn't ratchet closed, causing grinding and noise in the rear. At 300K miles, I wouldn't doubt it's seen better days anyways.

New shoes, 2 drum spring rebuild kits, and new drum cylinders (to push out the pistons) are relatively inexpensive to a new rear end.

Approximate prices:
Shoes: $20
2 Kits: $14
2 Wheel Cylinders: $20


Oh, a tool I got that makes life easier is the $8 drum pliers tool. Not necessary, but its easier than using a long flathead to stretch a spring.

Let us know what you find.

 

[AgPete139]

Of course, we all own Rangers and have probably long since crossed THAT line!

Uh, yea... truth! -------^

 

[Spott]

I would check the rear drum brakes.

...

Let us know what you find.

Yes, absolutely that first! Great thinking, Pete.

 

[black_demon69]

What he said. The "drive it until it completely fails" method can do more harm than good and leave you needing a ride home. Slow down and do some diagnosing. Wheels up, driveline disconnected, spin one side then the other, stuff like that. With 300k on it, it'd be easy to find yourself spending more than it's worth to fix it. Of course, we all own Rangers and have probably long since crossed THAT line!

Not drive till it dies method, the look and listen method (much easier to walk around when you are not driving it)

 

[swynx]

i read somewhere that if i jack it up and put pull the tire in all directions if there is no play then bearings are good? im gonna go down today and check it out.

 

[AgPete139]

Way to check wheel bearings:

Jack wheel off the ground.
Grab the tire, while still on the car, at 12:00 & 6:00 positions (top & bottom of tire), and wiggle it in & out. If it moves a lot, they are bad.
Very slight wiggle is "fine;" it can be a combination of worn suspension components and assembly slop. (Depends on the vehicle.)

Ideally, you want zero slop.