Rear Diff and Large Metal Shavings at 35K

Hi All,

Looking to get my first Tacoma from CarMax. 2020 SR5 4x4 with 46,000 miles. I was looking though the service history on the Toyota website and saw this from the tech at the 35K service.

"UPON DRAINING THE REAR DIFF FLUID, THERE WERE LARGE METAL SHAVINGS ON DRAIN PLUG" Should I run the other way, or might this be normal for a possible first-time fluid replacement..

Also, if it is a big issue would the drivetrain warranty cover the repair?

 

Swarf is normal.

Warranty provided by whom? Toyota likely expired based on year model?

Reading the warranty likely required.

 

AFAIK powertrain warranty is 5yrs/60K so there's a decent chance you're still covered.

 

Certainly something to bring up with CarMax. Presumably they inspect/review all of the cars they sell, so this would be something they have already addressed. If anything, they should specifically warranty this issue. The descriptor "large" is a bit ambiguous, though. If they were really large, the mechanic should have provided an opinion about what they might be, right? What's important is what the communication between the owner and the service agent. Also the communication between owner and CarMax upon sale.

It does make you wonder why the truck was sold to CarMax ... "Yep, needs a diff but got no money. Let's see how long I can drive before it becomes a significant issue!"

 

All good points. I think I have balance of 11 months left on the Toyota DT warranty. In my mind if the tech saw an issue at the 35K service and it was under warranty, why not just fix it. Why would the owner trade it 10K later if they could have got it fixed for free? I am taking it for a test drive later this week, anything I can tell when I drive it, or should I just get a Pre purchase inspection?

Other than this issue/question it was serviced every 5K at a dealer, so I am hoping it's a good vehicle..

 

There isn't a diff oil replacement in the maintenance booklet at 35k. It's either 15k if you tow a lot, or on-condition in normal use. The dealer likely upsold the previous owner on the diff oil replacement, so the truck may be better maintained than usual.

Some machining swarf is common to see. Check if the diff makes weird noises/chatter/howl during your test drive. If no weird noises then it's fine.

Yes the powertrain warranty would cover it if it fails within the 5yr/60k period. I suggest saving the maintenance record in case it disappears after title transfer.

 

Appreciate the guidance!! Last night I managed to get the full-service history from the Owners Dashboard but now its saying 'no service history' maybe the site is unreliable..

 

I actually did my 2nd maintenance on the rear diff at 60K. I have a piece of metal on the magnet that must have come loose after the first service. Still is fine with no signs of issues at 67K

 

Just remember that SOME 3rd gen rear diffs will howl slightly when you feather the throttle (in a specific speed range).
Mine has done it pretty much since day 1, with no issues (5 years and 60k miles later).