Skip to main content

Site Navigation

Your Account

Choose Language

What would cause metal shavings to be present in the rear-end fluid?

I have over a million miles on my 1994 W1A64T and at the last service, I noticed metal shavings on the fluid fill plug of the back rear-end. I would like to know what would typically cause the shavings, and if I need to replace the rear end or if it just needs some new bearings.

I am going to have the rear-end looked at today by a technician for their opinion, and every little bit of information helps.

I would also like to know if anyone has experience using a vehicle equipped with MicroBlue-treated bearings in the rear-ends.

Update

Jack and Jackie, thanks for the answers. I will be watching that rear end closely and will be getting it rebuilt or replaced soon.

Ron, the problem was so obvious the mechanic just took one look and figured it out. Jack and Jackie had the correct answers for the problem. We didn't even need to send the fluid to a lab to figure out the root cause.

Answered! View the answer I have this problem too

Is this a good question?

Score 1

Comments:

2nd update: The bearing and rear end went south as I was pulling in to pick up a load. The rear drive shaft broke in two, and the part that attaches to the rear shaft (the yoke) came completely free from the rear differential, causing the broken shaft to fall off. The shaft struck an air line and air bag, tearing those. Then, it fell off the truck... causing a tailgating car hit the broken shaft, ripped out an oil pan and tore up a transmission. Luckily, no one was hurt and neither me or the car who hit it is at fault (according to a DOT-certified officer at the Tilton, Illinois Police Department).

A MicroBlue back rear end and new splines are on order from the local Detroit Diesel shop in Saybrook, Illinois, along with a mechanic's inspection of the rig and the possibility of moving from it to a newer truck if the rig cannot be fixed at a reasonable cost. It was definitely time!

by

I'll bet that car never gets close to a truck again!

Sorry to hear of your trouble. Glad everyone is ok.

by

Update 3: MICROBLUE! I just got my new rear end, rear spline and had a couple of things done. It now takes 1 mile to slow 5 MPH on flat land while loaded when I let my foot off the accelerator... it used to take just 1/4 mile.

Also, the clutch needed adjustment and the air bag ride height needed to be dropped so the drive line angle was correct. Both of those were taken care of while the upgrade was being done. :-)

Oh, and did I mention the new rear ends my BO$$ specs now have MicroBLUE?!

by

Add a comment

5 Answers

Chosen Solution

It sounds like the ring and/ or pinion are going south. If it were bearings, you would probably hear/ feel it.

I see you are going to drive it as is..if so, keep a very close eye on it as once the gears start flaking they don't stop and the metal will ruin the bearings.

If it goes too far, you will end up on the side of the road somewhere.

I also have no experience with the Micro blue, so can't help with that.

Was this answer helpful?

Score 1

Comments:

Yep... it is the ring and pinion gear. It's stripped and it's time for a new rear end (preferably with MicroBlue treatment on the bearings).

by

I just got a new rear end with MicroBlue over the weekend and it totally changed the driving experience of this truck... (the MicroBlue rear end was cheaper than a brand-new input shaft, and took less time for the Detroit shop to install). If you want fuel mileage gains and/or want to roll down hills really fast to gain momentum for the next climb, I suggest getting the MicroBlue treatment myself.

by

Add a comment
Most Helpful Answer

The metal shavings are probably coming from the gears.

Get it inspected like you said your going to.

I have no experience with Micro blue myself but it sounds like a great upgrade. If you need your rear end rebuilt I would highly suggest getting the parts Micro blue treated.

Was this answer helpful?

Score 3

Comments:

I just had it inspected this morning and it looks like (for the time being) I will be running it as is (once the fluid is changed).

by

Ok, so time for Micro blue?

by

The mechanic did a much closer inspection and found a stripped ring and pinion gear. Also, he found the rear end was out of alignment. It's definitely time for MicroBlue!

by

Glad you caught it before it left you stranded.

by

The mechanic did not know what normal wear is in a rear end. The rear end finally failed today and I am very upset at the first mechanic who said I could keep running it. Luckily, a local Detroit shop is taking care of the issue now that it has finally failed. It should have been replaced when I caught the problem, not after the rear end failed completely!

by

Show 4 more comments

Add a comment

Sorry to hear it finnally failed before I could post, but if you go remanned rears with MicroBlue treated ones like I did should pick you up around 8/10ths mpg that has a great ROI.

Was this answer helpful?

Score 1

Comments:

It's my boss' policy to spec MicroBlue from the shop he works with now that he's seen the results. Not only is the MPG a huge improvement, but so is the driving experience. He bought the rear end and had the local Detroit shop put it on. Just having it made a huge improvement in how the truck runs! I can't wait to see some numbers in FuelGauges.

by

Good to hear about the Microblue experience.

by

Add a comment

if its alot or big chuncks. its a rear end going south as the gentlemen said. otherwise its just normal wear..

Was this answer helpful?

Score 1

Comments:

My problem has already been solved. Thanks for posting. :-) BTW, on the second day with the modifications, I noticed the fuel gauge moved slightly less than it normally does, a good indication of improved fuel economy. I'll still be posting on MyGauges and keeping track of the changes. The rear end went southbound and got replaced with a reman featuring the MicroBlue modification.

by

Add a comment

I would get a sample and get it on a rush for analysis ASAP

Was this answer helpful?

Score 0

Comments:

Then you should call Kevin or Artie (at OPS) or even the rear end manufacture and maybe with the results of what types of metals are present in the sample they could tell you where exactly it's coming from.

By the why what metals are showing up?

by

I found out the Ring and Pinion were going south- the gears were fine, but the input shaft had failed. Luckily, my boss had just the cure... a shop that carries reman rear ends with MicroBlue, along with a independent Detroit shop to install it. :-) Now, I'm climbin' hills faster and the truck just runs better. There is one side effect, though... It likes to live up to the truck manufacturer's name (According to Volvo Trucks, VOLVO= "Roll" in Swedish), especially on descents, so I better have the Jake ready.

by

Add a comment

Add your answer

Zachary will be eternally grateful.
View Statistics:

Past 24 Hours: 10

Past 7 Days: 69

Past 30 Days: 258

All Time: 14,266