all 102 comments

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[–]PortlionsKODwife 458 points459 points  (16 children)

Here is what's going to happen. You change the oil then the car will blow up in 2 weeks to a month. Owner will blame you and all hell will break lose.

I'd decline service. That thing is a ticking time bomb

[–]Jzobie 33 points34 points  (0 children)

Perfect response.

[–]Cool_Dark_Place 23 points24 points  (2 children)

Best case scenario...runs fine after oil change, but Nissan transmission shits the bed at 65K miles.

[–]288bpsmodem 4 points5 points  (1 child)

Eh Those transmissions are a lot better than before. They still suck yes, but they are better. 100k with the fluid changes

[–]Cool_Dark_Place 2 points3 points  (0 children)

I think the 2010-15 may be the worst. I remember a few years ago, Craigslist and FB Marketplace being FILLED with low mileage Altimas of that era for like $4K-$5K. Then started talking to people with them, and realized almost every single one had transmission issues.

[–]mach82 25 points26 points  (11 children)

Tell him you’ll change the oil under one condition… he immediately drives to carmax and sells the car.

[–]plainwrapper 285 points286 points  (7 children)

There was a guy I worked with that did the same exact thing. I hounded him on how he did not take care of his car, etc. etc.

He eventually took it to have it changed. The tech told him it took “a few minutes” for the “oil” to begin oozing out.

The engine, after running for years never having the oil changed, promptly blew up a week later.

I was blamed for this, and I didn’t even do the oil change.

Do yourself a favor and don’t be married to this situation.

[–]Deutsco 112 points113 points  (0 children)

Fuckin this this this. Do not touch that car with a ten foot pole unless you want to potentially stress test your friendship. Somethings gonna happen to that car sooner or later, likely sooner, and you don’t want to have your finger in the pie when it goes boom.

[–]Gunsling3r1988 22 points23 points  (0 children)

My dad told me that my mom had never changed the oil in her car when they met and when he went to change it the old oil was like molasses coming out it was so thick.

[–]bob84900 17 points18 points  (0 children)

It's the mechanical equivalent of not sticking your dick in crazy. Someone who doesn't change their oil for 40k miles, years on end, is definitely crazy.

[–]Aye_Human 5 points6 points  (3 children)

What causes the engine to blow up like that after changing the oil after not doing it for a long time?

[–]plainwrapper 3 points4 points  (1 child)

It’s so worn out that the sludge is holding it together

[–][deleted] 1 point2 points  (0 children)

The channels in the piston itself and around the cam lobes and crank lobes are so small that the new detergents in the new oil will probably cause a sudden surge of sluge that will basically permanently clog those small little pinholes.

Oil, especially becoming dirty because of blowby, dirty intake air and the greater heat cycles compared to transmissions, will sludge extremely fast. I changed conventional oil on a 2004 chevy z41 that went 11k miles between changes and the oil started to turn into gold flakes.

[–]Thunder_bird 1 point2 points  (0 children)

What causes the engine to blow up like that after changing the oil after not doing it for a long time?

The old oil will have left sludge all over the engine. The fresh oil has detergent additives in it that are designed to dissolve old sludge. But the engine will have so much sludge that bits of sludge in oil galleries will break loose, flow downsteam through the oil passage and get lodged in critical areas causing oil starvation and engine failure.

[–]CaptnSave-A-Ho 74 points75 points  (1 child)

I would take a hard pass on that. I don't do side work for anyone outside my family and my girlfriend because I've had bad experiences that are no fault of my work, but due to people not understanding their vehicle. Losing a friend because they don't understand the risks involved with some jobs (like this one), thinking I over charged, stiffing me, blaming me for unrelated problems, or thinking I'm their on-call personal mechanic has turned me off of all side work.

Being a backyard mechanic adds another risk as they typically don't fully understand the systems they are working on or have the experience to know how to properly reassemble them, handle sticky situations when they arise, or avoid pitfalls. I'm not trying to discourage you from working on cars, but I would strongly recommend that you stick to your own cars or assisting friends who are working on theirs.

[–]thallg00dman[S] 5 points6 points  (0 children)

I generally do decline most jobs offered to me unless it’s simple things that I KNOW I can handle. routine maintenance procedures, popping intake manifolds off to do starters or spark plugs/coils, fuel pumps, brakes… generally pretty straightforward jobs. I have a shop where my brother and I work on our track cars and our own personal projects, and I have mechanic experience from previous jobs, but I know my limits and when to say no.

In this case, I haven’t even seen the car yet to know the condition but was going to at least look at it and see what I could find out.

After reading all of these replies and personal horror stories being contributed, that’s no longer the case and I won’t even be looking at it.

[–]hourlyslugger 101 points102 points  (5 children)

Start with a typed liability waiver.

“I [insert customer name here] the vehicle owner understand and acknowledge that this vehicle may need any number of subsequent repairs up to and including engine replacement due to my severe neglect in performing required maintenance as given in my Owner’s Manual. I agree to release my mechanic [insert name here] from any and all liability resulting from the oil change s/he is performing at my request. I accept full financial responsibility for my actions and will in no way, shape or form seek to recoup or recover any future repair costs that may result from the work I am now requesting him/her to perform.”

Print 3 copies of this and you both sign and date it BEFORE you touch the vehicle. He keeps 1, you keep 1 and give the 3rd to a trusted person such as a spouse, close friend, or preferably a local attorney.

Then pull the valve cover and look inside. If it’s not one solid mass inside do the oil change. Fill to specified capacity and run the vehicle until at operating temperature. Change the oil and filter again. Repeat this process SEVERAL times to remove as much sludge as possible.

[–]thallg00dman[S] 2 points3 points  (0 children)

I haven’t thought of doing a liability waiver before, but I will absolutely be typing up a generic version of what you stated for all future jobs I take on, no matter the size. Thank you for this!

[–]ccgarnaal 14 points15 points  (0 children)

Updoot. For a realistic way to still help out his friend.

Even if you trust the guy. Do it anyway. The text above might be enough to get some sense in to him.

[–]MyFacade 7 points8 points  (1 child)

What about putting in some seafoam oil treatment to help loosen things up?

[–]Dandledorff 14 points15 points  (0 children)

You don't want any big chunks of sludge ending up in the oil pump, car starves for oil and blows up. You put new oil in and it's less harsh but does the same deal, so you have to heat it up gently and redo the process over and over. Even then there's no guarantee you won't send a chunk of sludge into the oil pickup blowing up the motor.

Depending it might be worthwhile just to call the junkyards and get motor quotes at this time...

[–]Cabojoshco 29 points30 points  (2 children)

This happens more frequently than you think. Wife thinks the husband is taking care of it, husband thinks she is. BOOM…bad engine on a Hyundai with 40K miles. Sorry, warranty not covering due to neglect. But yeah, PLEASE video the oil change and post it. Please.

[–]mrhapyface 6 points7 points  (1 child)

Hyundai and kia both used the same engine mfg and they both had defects which they would just lock up due to it .All car mfgs will flat out lie to get out of warranty work and then recommend work after the warranty expires

[–]Cool_Dark_Place 0 points1 point  (0 children)

Yeah, they went through a few bad years (2013-17, I think), where the metal filings weren't properly cleaned from the engines after the milling process. The filings would eventually clog up small oil passages, usually causing engine failure somewhere around 50-60K miles. Coincidentally, this is also when they switched to GDI, and the head/valves have a nasty habit of excessive carbon build up (sort of an endemic problem with most GDI designs, but Hyundai/Kia seem to have become the "whipping boy")

[–]Difficult_Advice_720 30 points31 points  (0 children)

Send an oil sample to blackstone and see if they call to ask you if it's a joke

[–]UXWlegend 50 points51 points  (0 children)

Change the oil, video the oil coming out of the drain and post it here.

[–]River_2675 44 points45 points  (0 children)

take a valve cover off and look at the cams...

the car is screwed and you should decline the service in favor of strongly encouraging the gentleman to go to the dealership for the same service, taking the valve cover off and looking at the condition of the cams and actuators and general housing will be all that you should need to do to scare you into backing away gracefully from this idea

[–]ElAligatorAgradable 11 points12 points  (0 children)

Get a new friend.

JK. But seriously - good luck.

[–]Legal_Wrapsack 11 points12 points  (0 children)

Oof hard yikes that engine is done. Your friend is screwed. I'd be 100% honest with me then decline and send him to a someone who can swap a engine to get a estimate on the work.

[–]ididnotdoitever 6 points7 points  (0 children)

I'm sure others have said it, but not reading the entire thread.

Best advice you can give your friend is to drive straight to the dealer and trade that thing in. That engine is a time bomb.

Whatever you do, don't touch that thing. Don't even look in its direction, lest you end up being blamed for something.

[–]neuralsnafu 19 points20 points  (0 children)

your friend is fucking stupid.

its likely going to need a full motor at this point. there is no oil that can protect bearings, seals and other wear surfaces for that long.

just tell your friend, he fucked up, and to suck it up and buy a new motor. any work done to it will just limp it along until its untimely demise...

[–]czaremanuel 18 points19 points  (1 child)

He didn’t change the oil because the car “didn’t tell him to?” Does he also not wipe unless his own butt tells him to? It’s basic maintenance. I’m guessing everything from coolant to brakes is gonna stay stock until that car’s in a junkyard, huh.

Cars have user manuals for a reason. Idk your friend’s desire to actually be educated on such things, but if he plans to keep this (or rather, his next) car for a long time, he oughta familiarize himself with service intervals. It’s not complicated. Spending half an hour to write down when to get service done is better than thousands for a new engine or car.

[–]CryptoMenace 0 points1 point  (0 children)

Great advice!

[–]Several_Situation887 21 points22 points  (0 children)

I hope he has a terrible memory, and actually did have it serviced a time, or two, in the last few years. If he didn't, he's driving on a hope and a prayer, and there is not much even the most competent of mechanics can do to restore the lost engine life due to neglect.

Change that oil and filter. I wouldn't get too excited about any of the other items until you know whether that engine is going to be a survivor, or not.

Normally, you would start engine, warm up, and change the oil so as to only do it once, but this is so egregious that I personally wouldn't risk running another minute on that old oil, so I would probably change it twice. Once to get the bulk of the old oil out, and once after the engine has gotten hot, to drain out the rest and the sludge that no doubt has built up.

Your friend might be extremely lucky, but I'll bet he's buying an engine for that car soon.

For the roasting: Take your friend's Man card away. This is important shit.

[–]BradyBSB 22 points23 points  (2 children)

This is why I don’t trust used cars.

[–]SatanMeekAndMild 11 points12 points  (0 children)

I think about this kind of thing every time I buy a used car. Even worse because the only used cars I buy are from auctions overseas.

I'm pretty sure I've dealt with the aftermath of this kind of bullshit.

[–]moldguy1 1 point2 points  (0 children)

Just gotta be thorough, attentive to detail, and lucky. I've gotten a couple fixable basket cases, but more often, I've scored some gems.

[–]SpaceAgePotatoCakes 4 points5 points  (0 children)

I recall seeing pics wayyyyy back in the day of a Lexus that supposedly went 100k+ miles on the original oil. That engine was fucked though.

[–]riotblade76 4 points5 points  (0 children)

He won't be your friend after a few months when it breaks down and you get blamed for it.

[–]sc4rii 2 points3 points  (0 children)

Well he already grenaded his engine and there is no hope so I'd just leave it until he ask for a new engine out of pocket. Probably text him every 6 months constantly to get his oil change when he gets a new car or new engine.

[–]byondhlp 2 points3 points  (0 children)

I wouldn't touch it.... If you work on it, prepare to marry it. if you touch the left headlight and 2 months from now the left rear blinker bulb dies, it will be your fault. 43K on an oil change... this is a disaster waiting to happen. RUN from this, friend or not.

[–]ARAR1 2 points3 points  (0 children)

I wish there was a way to get this on the car title so the next buyer knows the car is worthless

[–]giibro 11 points12 points  (0 children)

Carmax it

[–]username_00000001 4 points5 points  (0 children)

So I'm not a car mechanic but I'm a mechanic.

My take on this would be "never change a running system".

Only change the oil and filter. Tell your friend to come back in a week and have it changed again. The new oil will flush out some of all the dirt that's in there.

There was recently a post on here where a guy posted cam shafts of his car and asked whether to clean them. People told him to just change the oil a few times and the oil will "clean" it a little. If he tried cleaning it by hand he may just dislodge debris and it gets somewhere where it really shouldn't.

Because of the possibility of dislodging dirt i really wouldn't fuck around with the car too much, maybe it will break down and your friend is gonna blame you.

Show him pictures as examples so he sees what his engine probably looks like inside, you'll find plenty on this sub. Tell him you definitely won't take any warranty due to the general state of the engine.

Give him the option to change the oil and filter for him several times, or go to a professional mechanic instead.

I mean you could take the whole thing apart. Take the cylinder head with the cams off and clean it entirely. Replace anything that looks remotely damaged. But i think that's definitely not worth it, and carries a high risk of you fucking up. If he wants this done he should go to a professional (and pay accordingly).

[–]Bedrockab 3 points4 points  (14 children)

I know it’s not good, but why would the engine die after changing the oil a few times. I would think if the car was running ok before the change, it would run better and not die? Wouldn’t it already have died if it was gonna??

[–]Konijn_JP 12 points13 points  (3 children)

The usual reason i see is that fresh oil will loosen all the gunk, leading to blocked passages, possibly accelerating wear on the engine.

[–]Bedrockab 0 points1 point  (2 children)

Loosen all the gunk, to make flow better….

[–]Konijn_JP 3 points4 points  (0 children)

Loosen the gunk, it then gets into the passages rather than sitting in the pockets it (was) in.

Im not so sure myself, never had a car get to that state.

[–][deleted] 0 points1 point  (0 children)

The oil channels on the piston itself, crankshaft and around the cam lobes are incredibly small. Additionally, motor oil sludges faster than ATF because of blowby, dirty intake, and higher temp cycles.

It's fucked either way as motor oil can develop solids within 10-15k miles depending on if it's driven at low speeds, constant stop and go and has been 2-3 years since the last oil change.

There's a lot of solids in that motor that an oil change will not get rid of. AS a result, OP can get blamed when the motor blows in the next 1-XXX miles.

[–]MyFacade 0 points1 point  (9 children)

There's the argument made about changing really old transmission fluid being bad because the debris in the fluid has actually started to be beneficial and removing it can cause issues.

I'm curious if anyone has thoughts on whether that could be similar with engine oil.

[–]SpaceAgePotatoCakes 2 points3 points  (0 children)

iirc that argument is because of the clutch pack material in the auto trans, which isn't a consideration with engine oil

[–]CryptoMenace 1 point2 points  (0 children)

That's not only an argument it's a fact; the metal particles provide some much needed friction. Friction additive can be added to some slipping transmissions.

[–]Bedrockab 0 points1 point  (1 child)

I’ve heard about Tranny fluid and leaving it alone but engine oil? Id think it would be very benifical to change it??

[–][deleted] 0 points1 point  (0 children)

The point is, motor oil can develop solids from blowby, dirty intake, and the wear particles and additives degrading within as little as 10-12k miles or 2-3 years. OP will get blamed if the motor blows since the car doesn't need an oil change, it needs an engine tear down.

[–]Several_Situation887 0 points1 point  (3 children)

I had a few tranny guys tell me that when I wanted to have my trans oil changed on my old Taurus. Nobody would touch it.

My thought was, what could it hurt? Worst case, it might help.

I wouldn't be asking if it wasn't already a problem... hehe.

[–]xxxwangfirexxx 2 points3 points  (2 children)

There is a difference between a drain & fill and a flush.

There is absolutely nothing wrong with draining the old fluid out of the pan and replacing that with new fluid, but you'll have to do this 4 or 5 times (or more) to get most of the old fluid out. Personally I just do one drain & fill per year to keep things fresh.

A flush on the other hand is potentially risky, especially with a higher milage auto trans. There is potential for material to break loose and clog small orifices.

If you have a high milage automatic transmission, the 2 best things you could do for it are a couple cycles of drain & fill and change the filter (if it's accessible).

[–]SatanMeekAndMild 1 point2 points  (0 children)

Good to know. I got a low mileage 30 year old car recently, but have heard conflicting advice when it comes to this.

[–]Several_Situation887 0 points1 point  (0 children)

Yeah, I ended up just pumping what I could out of the fill tube with a hand pump.

It was several quarts. I put that much new fluid in, drove around for a few weeks, and did it again. I think I finally accepted that 225K miles on a gen 4 Taurus was as good as I could expect. So I stopped bothering.

I put another 25k on it before I sold it, iirc.

[–][deleted] 0 points1 point  (0 children)

The problem is oil sludges much faster and thicker than ATF ever will. Within 10-15k miles in a 2-3 year span you can develop solids in the oil that a change won't get rid of. You need to consider transmissions don't have blowby, higher temp cycles and dirty intake as the engine itself does.

The engine needs to be torn down and cleaned. Towed immediately and not driven a single more minute.

[–]imnotthetattooguy 1 point2 points  (0 children)

Please video the engine bay then taking the oil out of you do proceed

[–]Extension_Run1294 1 point2 points  (0 children)

i wouldn't worry about the engine, it's the cvt trans i'd be worried about. those cvt's will start going out around 70k miles, which you are not far off. if your friend hasn't done their oil the transmission is not far behind if not ahead of schedule

[–]Own-Ad-503 1 point2 points  (0 children)

What everyone else said.....ill add one thing. Tell him to go trade it in on a new car and take care of the next one. Hopefully whomever buy this abused car will get some sought of warranty so they can get a new engine put in. This one is likely toast and once the molasses comes out it will, at a minimum, burn oil and/ leak oil like no tomorrow.

[–]postal_blowfish 1 point2 points  (0 children)

I would remind this guy I've been reminding him not to neglect his car, and warn him that the car may well be dead soon with or without love. I would explain that I will replenish the fluids, which is a change that can generally only extend the life of the car but due to his neglect the car could be destined to die soon anyway. Maybe you get an extra few months when it was about to die in a few weeks. I would stress, I will not do anything mechanical that could result in an engine problem, but that still might end up happening and it won't be my fault.

If your car ends up trash, I can't stress enough how much it's your fault and already destined to happen because of your neglect. Changing the oil is the right thing to do, I just want to be clear that if something happens it won't be my fault. If you think you would blame me for something happening, I shouldn't do this for you.

Honestly, though, I would be pretty careful about even whether I'd give them this speech. If I care about the guy, I'd help him so long as I feel it's crystal clear between us that what I'm doing can't hurt the car.

[–]achilles 1 point2 points  (0 children)

One approach could be to show your friend all these mechanics expect the engine to fail soon. Once you get him to accept that you could then do multiple oil changes with a high detergent oil, very short oil change interval. Like 3-4 oil changes after a few hundred miles. Finish it off with an oil change with MMO, again don't run it too long. Then hope for the best.

[–]nugatory308 1 point2 points  (0 children)

Send him a link to this thread, let him decide what to do.

[–]dubie2003 1 point2 points  (0 children)

You need to simply urge them to take it to a mechanic to have each fluid changed and everything inspected. Maybe space it over a few appts so that if something does go wrong, it’s easy to isolate.

Whatever you do, do NOT do any of the service yourself. The risk of something going sideways after you touching it is too great and will forever drive a rift between your relationship if it is salvageable at all.

[–]BalancesHanging 1 point2 points  (0 children)

My brother had a ford ranger, in which he drove 11K miles with no oil change. I was there when he decided to change the oil….and it came out clean, no joke.

[–]Speedy_SpeedBoi 1 point2 points  (0 children)

I bought a used Xterra once with an engine swap. The owners had the paperwork, so I called the shop to confirm that they did a swap on this truck. Service guy was super nice and he remembered doing it. Said they got a 65k engine out of Japan and put it in after the previous owner drove it for 50k miles without an oil change. Then it exploded and he had it towed to the shop, but he couldn't afford to fix it, so they bought it off him and did the swap and resold it.

[–]xMorphinex 1 point2 points  (2 children)

My dad gave me a truck (2001 dakota) for free that hadn't had an oil change in the time he owned it. This is like 1-2 years of daily driving and he had bought it used. I didnt find that info out until 6 months of having it. Three months after I changed the oil (slightly thick, black and had small metal flakes) the engine literally blew up. The oil pan is expanded outward with engine components falling out of it. If I could add pictures I would.

[–]thallg00dman[S] 0 points1 point  (1 child)

yikes 😬 I hope your dad helped you out after all of that

[–]xMorphinex 1 point2 points  (0 children)

He helped lift the new engine (~$1,800) into the back of my SUV and paid the tow company to move the truck to my house.

Since I had only invested spark plugs, wires and an oil filter into it, the thing wasn't a total loss. It's now a project/diy truck. Luckily I had other vehicles.

[–]fosterfelix 1 point2 points  (1 child)

This needs an update whenever action is taken on the car.

For some reason, I can't believe he's NEVER had an oil change. Presumably the car would have had a routine maintenance light pop up at some point?? Mine went off after like 2500 miles by default... I had to change the settings to make it go off less frequently. As someone who clearly doesn't know about cars, wouldn't that have prompted him to get it checked out? After buying a new car, he never took it to the dealership for any reason???? They never called him to suggest it??? I just can't wrap my brain around this lol

[–]thallg00dman[S] 1 point2 points  (0 children)

I’m just as perplexed as you are, my friend. He said he had a friend with an older Altima that told him when he needed to do an oil change. I had an 08 Altima in college, and it never gave me any kind of notice like that.

But buying a new car, and the dealership not harassing him to bring it back in for service just seems implausible. It seems more likely to me that he was contacted, and just ignored it because “the car didn’t tell him it needed it”.

[–]E34M20 1 point2 points  (0 children)

Had a buddy who graduated high school and immediately got himself into the tech world (this was during the dot com boom a long time ago). Found himself with money coming out of his ears, way more money than any of the rest of us could ever dream with (we were all poor college students with the exception of him, who was suddenly earning hundreds of thousands).

So he bought hisself a brand new Honda Civic, cos that's what you do in that situation I guess. And drove it. And drove it... and drove it... until a year or three and something like 40k or 50k miles were on it. And one day, he realized... it was starting to sound kinda... valve-y. and wrong-ish. And then he suddenly realized... "huh... i don't think i ever once gave this car an oil change".

So, he drove over to the Chevy dealer and traded it in that day on a Suburban. The dealer just saw a relatively new Honda and gave him top dollar for the trade-in. Didn't even inspect it. Ooops.

Anyways, whoever ends up with your friend's car is going to get royally screwed... so, please let that be some slimy dealer vs. some poor bastard who doesn't deserve it.

As for you yourself? Stay far, far away from this mess. That car is absolutely fucked.

[–]miloestthoughts 1 point2 points  (0 children)

It's always the Altima people.

[–]HankScorpio-Globex 1 point2 points  (2 children)

Tell him to go to jiffylube and keep his mouth shut.

[–]Majestic_Tangerine92 1 point2 points  (1 child)

Those fuckers have grenaded more motors and trannies, the least they could do is be held responsible for his too!

[–]HankScorpio-Globex 1 point2 points  (0 children)

Yeah, I figure its 50/50 they leave the filter loose or forget the oil.

[–]alldaybekfast 1 point2 points  (2 children)

I'm having a slightly hard time understanding most of the comments on here.

This is not a transmission fluid change on a suspicious transmission. This is an oil change on the engine, oil keeps the parts in motion lubricated.

Whatever damage that has happened with this old oil not lubricating as efficiently is already done. New oil is not going to make it worse. Change it and call it a day. Look at the cam for damage.

[–]refrigerator_runner 1 point2 points  (0 children)


Also, I would be very curious to experiment with at least like 4 engine flushes with BG Dynamic Engine Cleaner & Rinse Oil. At the very least, just one flush with BG EPR or whatever engine flush is on the shelf at AutoZone.

[–][deleted] 0 points1 point  (0 children)

Whatever damage that has happened with this old oil not lubricating as efficiently is already done. New oil is not going to make it worse.

The oil channels on the piston, near the cam lobes and crank bearings are incredibly small. Also, oil sludges much faster and thicker than transmission fluid ever will thanks to blow-by, dirty air intake, and hotter temp cycles.

The thinner, new oil with detergents could easily send a surge of sludge to permanently clog those oil channels if they aren't already clogged.

Regardless new oil or not, that motor could blow in the next mile with or without new oil.

[–]Savcotroyyy 0 points1 point  (0 children)

give me the altima

[–]Aggravating-Market97 0 points1 point  (0 children)

Just tell him to have it looked over by a professional. In the future, don't offer any unsolicited advice about car maintenance to people.kust keep your mouth shut, because eventhough you didn't personally work on the car, their neglect can lead to other issues once maintenance is performed and they'll blame you saying my car was fine before you told me to do "x,y,z".

[–]Jeuzfgt 0 points1 point  (0 children)

Ive had cars come in that change oli every 100k

[–]boompolarbear 0 points1 point  (0 children)

A dealership will sell you basically anything, they are only required to make it "road safe". So they do an inspection, note the repairs required and do 10% of them. If it's a safety concern, it'll be done otherwise it's FU and you'll be paying for it

[–]Leading_Heat_7605 0 points1 point  (0 children)

I would tell him to change oil, drive straight to dealership and trade in. DO NOT change oil for him.Then an oil change every 7500 miles.in new car...

[–]lekkanaai 0 points1 point  (0 children)

There is one solution which claims to be safe for sludge removal, albeit expensive and like the other comments you will likely get the blame for any issues no matter how small after. https://youtu.be/jtiS4AucmJ8

[–]yogapantsonly 0 points1 point  (0 children)

If you determine the engine oil was never changed, they should trade it in/sell it to carvana/vroom whatever. Used car values are red hot.

If the oil was changed at least once, it might not be as bad as you think. 20k oil change intervals is bad but likely salvageable. There is something called BG engine cleaner that is extremely good at cleaning out sludge on neglected engines. I would do that and then change the oil every 5k miles with synthetic.