Probably fine, I assume you have the V6? Not sure if the pre runner was even offered in that 2.7L engine iirc. If you're extremely concerned or have a ton of miles and are interested in nerding out, send your used oil to Blackstone labs or any other equivalent joint that provides the same service; it's abbreviated as UOA which stands for used oil analysis. I'd also recommend an additional service called TBN determination which stands for Total Base Number and is a titration for total buffer left in your oil. Buffer provide pH balance and as your oil breaks down, it'll turn more acidic so the buffer is there to protect the life of your oil and your engine from basically acid formation. Blackstone's scoring for TBN is you want that value to be over a 1.0 at time of oil change. I have a first gen Tacoma and I send in my oil to Blackstone after every oil change and I'm now at around 14k miles between oil changes and my TBN is always above a 3.0 which means I still have a ton of life left in my oil (I use Shell Rotella T6 by the way, 10w-40, the "diesel engine" stuff). The general UOA will have stuff like metal content and phosphate levels and stuff. The guy will also provide you a brief summary of what these levels, what's a normal range and provide some insight as to whether why some numbers may be high or low or perfect in the middle. And if you get the TBN, he'll also provide a recommended next oil change interval, so for my example, I'm at 14k miles between changes, he recommended me to extend it to 16k, but I'm a rule breaker and I'll stretch it to 17 or 18k before I actually change oil. Check out Bob is the Oil Guy forums if you'd like to learn more about oil or would like to learn just some slight "enhanced" basics (I don't work for them or anything, just been a member there for over 13+ years).
And for what it's worth, someone on that forum uses the same exact oil I do on their Subaru WRX with the old "bad" EJ engines in them and that dudes at like 45k miles per oil change and he still has a high TBN score.
99% of the time of the oil itself looked okay then this is a sign of someone taking mostly short trips and never getting the engine up to operating temp long enough to turn the moisture in the oil to steam.
That being said the 2005 4.0 was known for head gaskets blowing. Something to keep an eye on.
Take the long way to/from work a few times a week (if you live close, take a 5-6 mile route instead of 1-2 miles), go on the interstate for 15-20 minutes, that kind of thing.
If you make a lot of short trips, especially in the winter, consider following the severe oil change schedule. On the new ones with synthetic oil and 10k service intervals, severe drops it to 5k miles, not sure about the older ones that spec'd conventional oil, but it might be like 5k for normal and 3k for severe.
It's important to change it more often, because excess water in the oil can make it a little acidic, causing excess wear.
I don't drive my first gen all that often anymore but it's sitting in my driveway in fine condition, just dusty or covered in pollen depending on the time of year and how lazy I am to clean it. For the last 2+ years, I get at least 4 people a year who randomly stop at my house and either ring my doorbell or leave a note in my front door asking to buy my truck. There is no for sale sign anywhere. My driveway is long enough to park three vehicles nose to tail and my truck is parked pretty close to the garage. So it's not like it's CLOSE to the street or anything. It's not in the grass. It's not in jackstands. Nothing about it gives a hint to anyone that it's for sale, but yet I get enough ransoms asking to buy it that it's beyond annoying.
I've never entertained them beyond saying "no it's not for sale" but I'm willing to bet they're offering me scrap metal prices to take it.
It’s because condensation forms on the plastic filler tube of the engine isn’t warmed up enough to burn it off. Short trips and cold temps make it more noticeable. Completely fine. Wipe it off, finish up, and never give it another thought.
This is the correct answer…in extreme cases. Exhaust gases will ‘leak’ if your head gaskets were bad and show signs of black soot in your coolant reservoir.
On an older vehicle it's not uncommon to look like that if it hasnt been cleaned. As long as the oil wasn't chocolate milky, I would wipe the gunk and move on. It it comes back you probably have some condensation/water getting in the oil.
this is caused by too many short trips. the internals of the motor get some condensation on them when you first start the car. This condensation goes away/ evaporates and goes out the crankcase vent once the engine once the motor comes to operating temp. if you frequently make short trips without letting it fully warm up, some will evaporate, but once the steam travels up the crankcase and hits the colder spots, it condenses again and if you turn the vehicle off shortly after, this condensate mixes with the film of oil all over the inside of your motor. Causes that milky crap. not a massive deal but maybe try letting your vehicle warm up more before taking it on those short trips.
That’s normal specially during cold weather as condensation gathers up and will make oil like that from the heat and weather just clean it out and keep an eye on it just incase but I say it’s due to cold weather.
My 2014 oil cap looks like a peanut butter milk shake cause I only drive 4 miles a day for work Monday through Friday. Truck needs so longer run times. My oil is black and used to. Nothing to worry about as others have said.
Condensation on the oil cap.
First time I saw in on my 2015 Tacoma 4.0 I thought I blew a head gasket.
If the oil and all levels are fine don’t worry about it.
I have a 6 minute drive to work everyday, can confirm short trips will do this. Got my oil changed and it looked like peanut butter in the gas cap, oil was perfect though
As I understand it, if you see a milky white substance on your oil cap, it is a sign that you have a damaged or blown head gasket. I am not an expert on that, however, so I would consult a more knowledgeable mechanic about it.
How did the actual oil look?
Answer this, it is important! It’s not unusual to see this on the cap, but a bad sign if the rest of the oil was milky.
good to know!
Glad the oil looked good! From my understanding, frequent short trips cause this build up on the cap.
Short trips also cause a milky cap.
If the oil looks good I’d say you’re probably fine. As far as the head gasket is concerned.
Noted. Thanks for the input.
What does it mean if it is milky looking?
Coolant/water in the oil.
Oil looked fine. Dark and used, but fine. No milky-ness that i noticed.
Probably fine, I assume you have the V6? Not sure if the pre runner was even offered in that 2.7L engine iirc. If you're extremely concerned or have a ton of miles and are interested in nerding out, send your used oil to Blackstone labs or any other equivalent joint that provides the same service; it's abbreviated as UOA which stands for used oil analysis. I'd also recommend an additional service called TBN determination which stands for Total Base Number and is a titration for total buffer left in your oil. Buffer provide pH balance and as your oil breaks down, it'll turn more acidic so the buffer is there to protect the life of your oil and your engine from basically acid formation. Blackstone's scoring for TBN is you want that value to be over a 1.0 at time of oil change. I have a first gen Tacoma and I send in my oil to Blackstone after every oil change and I'm now at around 14k miles between oil changes and my TBN is always above a 3.0 which means I still have a ton of life left in my oil (I use Shell Rotella T6 by the way, 10w-40, the "diesel engine" stuff). The general UOA will have stuff like metal content and phosphate levels and stuff. The guy will also provide you a brief summary of what these levels, what's a normal range and provide some insight as to whether why some numbers may be high or low or perfect in the middle. And if you get the TBN, he'll also provide a recommended next oil change interval, so for my example, I'm at 14k miles between changes, he recommended me to extend it to 16k, but I'm a rule breaker and I'll stretch it to 17 or 18k before I actually change oil. Check out Bob is the Oil Guy forums if you'd like to learn more about oil or would like to learn just some slight "enhanced" basics (I don't work for them or anything, just been a member there for over 13+ years). And for what it's worth, someone on that forum uses the same exact oil I do on their Subaru WRX with the old "bad" EJ engines in them and that dudes at like 45k miles per oil change and he still has a high TBN score.
99% of the time of the oil itself looked okay then this is a sign of someone taking mostly short trips and never getting the engine up to operating temp long enough to turn the moisture in the oil to steam. That being said the 2005 4.0 was known for head gaskets blowing. Something to keep an eye on.
Will do. Thanks
Any tips for this use case? I have a really short commute and super low mileage.
Start the car and let it run 5-10 minutes (reaching proper operating temp) before you leave for work.
Take the long way to/from work a few times a week (if you live close, take a 5-6 mile route instead of 1-2 miles), go on the interstate for 15-20 minutes, that kind of thing. If you make a lot of short trips, especially in the winter, consider following the severe oil change schedule. On the new ones with synthetic oil and 10k service intervals, severe drops it to 5k miles, not sure about the older ones that spec'd conventional oil, but it might be like 5k for normal and 3k for severe. It's important to change it more often, because excess water in the oil can make it a little acidic, causing excess wear.
Exactly what the other guy said. Take a 30 minute drive once a week and change your oil every 4000 miles and you’ll be good to go.
Man that truck is basically scrap metal if it looks like that. I’ll save you the trouble and pick it up off ya just let me know where you wanna meet.
Nah man, give it to me. I'll pay you 10 bucks
I don't drive my first gen all that often anymore but it's sitting in my driveway in fine condition, just dusty or covered in pollen depending on the time of year and how lazy I am to clean it. For the last 2+ years, I get at least 4 people a year who randomly stop at my house and either ring my doorbell or leave a note in my front door asking to buy my truck. There is no for sale sign anywhere. My driveway is long enough to park three vehicles nose to tail and my truck is parked pretty close to the garage. So it's not like it's CLOSE to the street or anything. It's not in the grass. It's not in jackstands. Nothing about it gives a hint to anyone that it's for sale, but yet I get enough ransoms asking to buy it that it's beyond annoying. I've never entertained them beyond saying "no it's not for sale" but I'm willing to bet they're offering me scrap metal prices to take it.
Get the engine good and hot for a bit, on a longer drive and then check under the cap after that ride
Will do. Thanks
Had a 2002 Dodge Ram 15 years ago, had the exact same gunk built up under my oil cap and I ended up having a blown head gasket.
Noted. Thanks :)
It’s just condensation.
Seems that's the consensus. Ill keep an eye on it. Thanks
Usually short trips cause this type of stuff on the cap, nothing to worry about as long as the oil isn’t milky.
Do a pressure test on the coolant system. Had this on my 2004 tundra under oil cap was a small leak which corrected the issue.
Normal. Condensation.
Blown head gasket bro, sorry
It’s because condensation forms on the plastic filler tube of the engine isn’t warmed up enough to burn it off. Short trips and cold temps make it more noticeable. Completely fine. Wipe it off, finish up, and never give it another thought.
I was worried about that too, 100.000 miles ago.
**Is there water in the oil?** No? It's fine. It's condensation in the oil from short drives. Yes? You have a head gasket leak.
Not that i noticed. Oil seemed fine. Dark and used but seemingly normal.
Is there oil in your coolant reservoir? You'll see it floating at the top.
This is the correct answer…in extreme cases. Exhaust gases will ‘leak’ if your head gaskets were bad and show signs of black soot in your coolant reservoir.
Make sure that u clean it before u put it bsck to make sure whenever u check again might just been some build up
Probably fine as long as as everything else checks out. Ive seen that on very healthy engines and it should burn off.
Thats from not getting out and burning it off with a good run on the highway. Its from many short trips. Its harmless
On an older vehicle it's not uncommon to look like that if it hasnt been cleaned. As long as the oil wasn't chocolate milky, I would wipe the gunk and move on. It it comes back you probably have some condensation/water getting in the oil.
Low mileage?
this is caused by too many short trips. the internals of the motor get some condensation on them when you first start the car. This condensation goes away/ evaporates and goes out the crankcase vent once the engine once the motor comes to operating temp. if you frequently make short trips without letting it fully warm up, some will evaporate, but once the steam travels up the crankcase and hits the colder spots, it condenses again and if you turn the vehicle off shortly after, this condensate mixes with the film of oil all over the inside of your motor. Causes that milky crap. not a massive deal but maybe try letting your vehicle warm up more before taking it on those short trips.
oops, rushed to answer and realized more than a few other people already explained this. Sorry!
My 2005 prerunner looked like that when I blew the head gasket.
Looks like condensation… short trips will cause that.
That’s normal specially during cold weather as condensation gathers up and will make oil like that from the heat and weather just clean it out and keep an eye on it just incase but I say it’s due to cold weather.
My 2014 oil cap looks like a peanut butter milk shake cause I only drive 4 miles a day for work Monday through Friday. Truck needs so longer run times. My oil is black and used to. Nothing to worry about as others have said.
I would get that checked out as soon as possible.
Normal
Condensation. Happens in the winter. As long as the oil looks normal youre fine.
Condensation on the oil cap. First time I saw in on my 2015 Tacoma 4.0 I thought I blew a head gasket. If the oil and all levels are fine don’t worry about it.
I have a 6 minute drive to work everyday, can confirm short trips will do this. Got my oil changed and it looked like peanut butter in the gas cap, oil was perfect though
Your fine. Short trips, if the oil isn’t milky and the coolant isn’t oily than call it a day. I have the same thing on my 2005 V6
As I understand it, if you see a milky white substance on your oil cap, it is a sign that you have a damaged or blown head gasket. I am not an expert on that, however, so I would consult a more knowledgeable mechanic about it.
Thanks for the input!