What says the wise forum?

I am thinking head gasket. Was in process of changing my oil when I spotted this. The drained oil was fine and the coolant is still pink. However my reservoir is almost empty.

 

Okay, so how many miles have you went in between oil changes and do you top off your coolant reservoir everytime you change your oil?

This is a preliminary until you answer my above questions, but that is not a head gasket, that is condensation mixed with oil due to how far up the oil cap is in relation to the valve cover. I get it on mine too as do many many other people and I know I don't have a blown head gasket.

 

I do about 10k between oil changes and generally add if needed but don't necessarily top off. I run mobile 1 synthetic extnded milage for high milage engines.The truck has 188k

 

This is normal if you do a lot of short drives.

 

A lot of short trips ? If so, that’s just condensation, nothing to worry about, normal.

 

If your coolant system works properly, you shouldn’t need to top it off. The expansion tank will fill when the coolant gets hot and expands. When it cools, it will be pulled back into the radiator. Coolant should be around the marked line at cold.
What you are looking at may be condensation. I imagine it’s humid in Corpus, so the condensation point his higher. What you could do is pull your plugs and see if any look steam cleaned. Do you notice any steam from the exhaust? If you do have coolant contamination, you should stop driving it immediately, or you will cook your rod bearings right away.
If your oil is normal color, it’s more likely condensation than contamination.

 

Well no wonder your coolant is low.

10K is too long in between oil changes. If you don't believe me, pull your valve covers off and see how black and disgusting your internals look. No more than 5K. Anything more you are doing yourself a disservice in the long term for a short term gain.

Your truck is fine. That is just condensation on the cap.

 

Ok well my wife was driving it while I was in Japan and she was doing short trips to work. So I will monitor and see if it continues now that I am back home. Never had that happen before thanks for all the feedback.

 

Actually under my valve covers look clean as hell. Your right if I was using an traditional oil that is way to long however I am running a full synthetic oil. These newer oils can and do last a lot longer than traditional oils. But that is neither here nor there as the point of this post was not about what I believe or you believe a schedule oil change should be performed at. Your opinion is noted thanks for the feed back.

 

If you determine it’s nothing more than condensation, you may consider periodically letting it idle at temp for a little bit with the cap off to evaporate the condensation out. It probably isn’t hurting it, but it isn’t helping it either. I would definitely do that if you are going 10K between oil changes. Clean that cap and monitor it. I check oil, fluids, and tires weekly in our cars. They are all virtually new, I’m just a little preventative driven. I especially don’t want my wife or daughter getting stuck somewhere, or fixing something at 2:00 AM on a workday, I could have seen coming.

 

I think burning only top tier gas will put an end to that crud. I do mostly short trips and I don’t have that problem. I always avoid the cheap gas stations, there’s probably a reason there gas is cheap.

 

There are Tacoma's with 1 million miles on them that used 10,000 mile oil changes. 10,000 miles is conservative. I have 3 vehicles in the driveway with almost 1/2 million combined miles. I've been doing 10,000 mile oil changes for 20 years with no issues.

 

It doesn't make a difference. I run 91 Shell or Chevron only in my truck, the same junk pops up on my trucks cap regularly and I give mine full beans regularly. Full 6000 RPM runs on it and I get it to temp on long drives. It's just a Tacoma valve cover oil filler neck thing.

I'm not getting into that topic nor do I want this thread to turn into that either. If you guys want to run your oil changes 10,000 miles then that's you guys' prerogative.

 

No one addressing your statement that your coolant reservoir was almost empty, it’s gone somewhere. Keep your eye on it and see how fast you lose coolant. Look for external leaks.

Oil change intervals have nothing to do with coolant loss. My goodness.

 

have you performed a block test? No.
Are you losing coolant and burning it through the exhaust? No.
A block test kit with fluid is $40.
Milky substance can also happen from frequent short trips that don’t give the oil enough time at warm operating temp to get rid of any condensation.

but if you want to jump straight skip to thousands on a head gasket you sure can

coolant level is checked cold via the radiator. The extra amount in the reservoir is supposed to fluctuate and get sucked in and out depending on the operating pressure and temperature of the cooling system. That is why they are usually called an expansion tank. Which probably barely even functions that way on the Tacoma vs other cars because other car reservoirs have a pressure sealing tight fitting cap, and the taco reservoir cap is not.

 

I addressed part of it earlier because topping off the reservoir was suggested. It’s an expansion tank, and it will fill and empty with temp. While it shouldn’t go dry, it shouldn’t be filled to the top when cool. If it is, it will likely burp out the excess. There is a line on it for a cold engine. A pressure test will help determine if the coolant is escaping or there is a cooling system issue. Loss to evaporation should be close to insignificant if your system is closed and the coolant is properly balanced.
Evaporating the water out of the coolant may be as simple as a bad cap. When they get old, sometimes they stop sealing.

 

does not hurt to do a pressure test. Both to watch for any leaks and to leave the tester hooked up to check for PSI loss over time. It is fast and easy. I don’t know the operating pressure off the top of my head. Probably around 15psi

 

When's the last time you changed your PCV valve?

There should be a little vacuum line from the right valve cover to just downstream of the MAF if there's oil in there at all your PCV on the back if the left valve cover is blocked and needs replaced.

 

Don't hit the panic button just yet. Just keep an eye on the coolant level. Instead of glancing at the level every 10k, check it once a week for a couple months. If it's steadily going down then worry about a leak.

But also remember, it can be fairly normal to lose a little bit of coolant over a long-ish period of time. If the level hasn't been topped off for a good while don't overthink it. Just top it off and start checking it more often