Sludge Concerns

I took a 700 mile road trip in my 2015, at just under 118k and doing a synthetic oil change. I’ll admit, my truck had a brutal time in early 2024 and I was without it for a good 11 weeks.

When I got it back, having moved far-away, I found it hadn’t been put back together correctly. Lots of wind noise and water seeping in under the pass footwell during washes or heavy precipitation. I had to eat the bitter pill and not do anything about it, from late March to present. Dealer responsible was too faraway and local network wanted hundreds to identify the source.

Got my catalytic converter cut out in June and stolen at night in a seedy commercial district. I was once again without my truck for a month and put in a 3rd gen SR5 rental by insurance.

Having been hearing since March, a rattling noise at idle, which I presume to be related to the throwout bearing, I’ve still sucked it up and driven this truck regardless, but also went without an oil change from February/early March to December, particularly when my Toyota dealer insisted it was NOT necessary to change the oil yet back in September.

Now that I am headed back home roundtrip, I decided to curiously have my truck appraised by CarMax for kicks and see if there’s anything I missed with my own little inspections.

They claim that they found oil sludge and 4WD issues, which has me wondering if the sludge is residual and nothing to worry about over 650 miles of long distance driving. Or am I taking a dumbass risk, driving 9.5 hours back?

Because of my truck not feeling so great since a major repair last year (not my fault) and then replacing the stolen cat, on my way here last month, I drove at a snail’s pace.

At 66 in a 75-85 MPH zone on the right, 70% of my journey with 2 long rest breaks. Only the last third of my trip, I did the speed limit of 75-80.

Should I take what they said seriously about the sludge or treat it as a nothingburger?

 

Need to Change the Title....

 

I’d continue to drive it and monitor the oil level and condition.
You don’t just clean sludge out of an engine easily. You can add oil additive that help break it down.
But it’s not “that easy”. The better ones are a process, and require multiple oil changes in a short period of time. And even then, it’s not “clean”.

Personally, I drive it as normal.
If you have issues, you have issue.
If you don’t, great. Money saved.

If you really want, you can stick an inspection camera done the oil cap hole.
Have a look at the “sludge”.

 

My mistake

Thanks, appreciate it man. Very greatly

 

Did the CarMax jockey give sludge evidence, or just say there was?

What was the evidence?

How many miles on your current synthetic oil?

 

The latter. I saw the printed out appraisal and looked at any condition concerns. That was what they mentioned. I asked the rep and he said, it was simply that they noticed it and possibly it was just residual. I don’t have any evidence.

Typically when it comes to Toyota, I’ve only heard about sludge with the old MZ V6s in 90s and early 2000s FWD models. RWD VZ V6s didn’t seem to be affected nor GR series V6s.

I did my last oil change at 118,421 the Saturday right before Xmas and currently at 120,021.

 

I’ll 2nd this. Many bad experiences out there with Carmax, my ex bought a Nissan maxima there back in the day. Spiders nests throughout causing her to have panic attacks so she took it back but it was after the 3days so they offered her a buyback for 1/2 the price she paid. Claiming it had been in an accident and she had frame damage.

They will always jockey you around and blow smoke to make a $…

OP: When you say “put back together” was it in an accident or what was the repair? Water leaking in on the floor is likely a leaking cowl vent, common on our trucks, there are several easy DIY fixes if you search or look in the FAQs.
Does the rattle at idle go away when you push the clutch pedal in, easiest test for throwout bearing.
Are you having problems with 4wd? Does it engage in hi & lo? Noises?

I’d definitely change the oil for starts. Make sure the oils good & hot before u do. Maybe do an oil analysis?

 

My guess is he saw the very common white material in the oil fill cap which is meaningless (lots of threads on it here)

So you've got less than 2k on syn oil and under a month of time? Just make sure it's full and drive it.

Do YOU have any 4WD issues? It's possible the same 'inspector' didn't know how to properly put it in 4H then 4L. Lots of owners here complain about 4wd engagement problems and most of the time it's lack of experience.

 

I'll have to agree with Clearwater and say your oil sludge was under the oil fill cap. Common for short drives and nothing to worry about.

 

Depending on the severity of the SLUDGE you can use this https://rogue-offroad.com/LIQUI-MOLY-500mL-Pro-Line-Engine-Flush_p_20057.html. But we recommend a few oil changes in close succession after to help not cause a filter restriction and not move more sludge in the engine. Follow up with a High-quality oil like LM which we have packages. We would recommend doing 2-3 oil changes at 3k or less if the engine has sludge and you use the flush. And 1-2 treatments of flush in the 9-10k mile time frame.

But again depends on the severity of the sludge.
Ultimately it can be fine but you do run the risk of clogging certain oil passages and ending up with larger repair bills. We had a 4.0 that ran a popular oil brand and only drove a few miles each day, got sludge build-up and it prompted a check engine that no one could get to go away. The solution was to change the engine at that point or rebuild. But this was a bad case that you could see it on the dip stick.

 

Send it. Good luck.

 

Been a busy evening, so just seeing this now.

Had to replace transmission, clutch (again), some associated clutch components, and 2 shocks due to shoddy repair work on the truck leading to a major transmission failure. Took extremely long for new transmission to arrive, being ordered in early Feb. Flying back and forth every damn weekend early last year from late Jan to mid-March, because previous dealer couldn’t get it right for some 2-3 weeks and I was still in the process of moving, while starting new job 700 miles away. During that period, previous dealer also did first synthetic oil change after new transmission was installed in late February.

Being tired of waiting by mid March, I noticed when preparing to have truck freighted to me before my flight back, I was hearing a lot more road noise than ever. At the dealer Saturday morning, the radio was blasting, so I didn’t notice immense noise until Sunday night, when I would be going to work the next morning. It was too late to drive back to the dealer and have them investigate the road noise, because I had work 700mi away and a redeye flight to catch.

I complained to them during my lunch break by phone and they of course said I “could bring it back in”. I couldn’t. Being one of the shittiest situations I’ve dealt with ever on a vehicle, I spent 5 figures including tens of rental vehicles and last minute flights on my own dime and the cost of the new transmission. I was at the end of my wits and just gave up, having the truck freighted over to me at my new residence 650 miles away.

I found over the course of late March and April, water pouring in. So, I’ve been at a loss, that it feels like I’m driving a claptrap.

The rattling noise at idle? Yes, it goes away when I push in the clutch pedal. Once released, it rattles again.

As for the 4WD?

I went slightly offroad last week, to access a remote desert area for recreational shooting and other than an extremely bumpy ride, no issues, getting in or out. CarMax claimed on the sheet “4x4: Slipping”.

When weather warms up a little tomorrow, I’ll try and check it for sure. Thanks for the response.

Yes, that’s correct. Changed it before my trip, took off 26 hours later.

Sorry, forgot to note that the reason I noticed anything about 4WD was on the sheet “4x4: Slipping”. I asked why they claimed this and the answer was, “Oh, it probably just needs some servicing done”.

Thanks for your reply.

That’s what I actually saw in another thread on TW from 2020, thanks for that insight BTW.

It’s something I didn’t care to think much of, but when you work remotely, who’s exactly in a rush to drive 9.5 hours if anything random pops?

Thank you for this detailed reply, I am going to do vet the truck tomorrow as you’ve advised and see if I am good to go for a Wednesday morning return or if I need to look much deeper.

 

Jump get rid of and start with something new. Sounds like you have too many thoughts about it in your head from all the drama.

 

Oh man, seriously? It’s logical, but I really love my truck despite my issues. I got really lowballed by CarMax, but book value at least is reasonable to me still.

Honestly keen on keeping it, but how realistic that is, definitely a different question.

 

If you been changing the oil regularly every 5000-7500 miles. You dont have sludge in the motor.

 

I would say first of all youre neglecting things on your own part,
The dealer doesnt twist your arm & say under no circumstance, youre not allowed to change your oil....
Not knowing the severity of the t/o bearing condition, could be doing more harm than good, but you decided to just drive it anyway...

Did you look inside the oil cap for yourself, along with inside the oil fill neck, & pull the actual dipstick & inspect condition of oil along with any foreign stuff that should be there?
You obviously did have carmax point out their findings...

This is pretty simple. Post some clear pics of inside your oil cap, your oil fill neck, your dipstick....

How many miles on the actual oil in your truck now???
Dont mean to bash but seeing this alot, little bit of money spent on maintenance saves you big time in the long run...
You guys should price an engine & labor these days.....

If you truly have sludge to the point carmax is noting it, legit sludge, not just cartoned oil on the inside of your cap, you missed more than 1 oil change or have other issues...
but without pics & you not looking for yourself, its anybodies guess.

you also stated you were wondering if the sludge was residual...
Residual from what?
Youre not suppose to have sludge, its from lack of oil changes done within proper intervals...
Takes more than 1 time neglecting to perform an oil change.
Even if you put some magic snake oil that claims in automagically makes sludge just go away, the damage is done.......
The sludge isn't the issue, its everything that is internally happening too your bearings & internals that was happening due to lack of proper maintenance that caused the sludge.

ok, ok, im done ranting but ive seen this sooooo many times.
It infuriates me....

Or the carmax inspector is a clown & nit-picking & this was unwarranted, sorry.

Pics would clearly give a real picture of what may be going on...

 

But does 4wd “slip”?? It either engages or it doesn’t…

 

Well, unfortunately it wasn’t changed for 10k miles from February to December.

Wanted to investigate under the hood today, things did come up and wasn’t able to. Now it’s dark, so tomorrow.

I went off of what CarMax implied and not my own assumptions. When I serviced the truck in December, truck was given a clean bill of health and driven 640 miles West. Driven another 1k up until yesterday locally.

I had mentioned above in my post to @Clearwater Bill, that I last changed the oil at 118,421 and just passed over 120k. Synthetic oil changes were done at 108.3k and 118.4k in 2024. Not the most sensible idea, but extremely rough and chaotic year, scattered into pieces. Reason I even stayed longer, is one very sick parent.

Seemed to engage without issue last week in the desert. I try to limit use of it on pavement, so no I haven’t activated it again.

 

pictures, lets see if carmax warranted the documentation...

 

Definitely. Since it’s dark, I’ll do that tomorrow. I hope that in all of last year’s chaos, I haven’t torpedoed things for good. TBH, truck has had many owners…

Market for 1GR-FE V6, 6MT TRD ORs below $30k was horribly limited 18 months ago and all the perfect specimens got sold, leaving me with so-so examples for sale.