How often do you top off fluids?
Posted by Practical_Card5032@reddit | askcarguys | View on Reddit | 45 comments
New to working on cars as the only thing I have done so far are oil changes and brake pads.
I want to get better at understanding different car fluids and how often I should top them off (brake fluid, coolant, transmission fluid, washer fluid, power steering fluid)?
Is it better to do a complete flush or is it okay to top them off? And if so, how often should I do it?
Thanks!
JollyGreenGigantor@reddit
You shouldn't need to top anything off. Read your owners manual for scheduled maintenance and replace your fluids as needed.
It's a good idea to check all your fluids once every month or two depending on how much you drive. But also, read the manual to see if you should do level checks on a hot motor, cold motor, hot motor that has cooled for a bit, etc. Newer cars have some fluids that can last forever without a change (like coolant and some engine oil) and others that need more frequent changes than older cars (high performance brake fluids).
Dangerous_Echidna229@reddit
Coolant and engine oil last forever. Tell me who says this.
JollyGreenGigantor@reddit
My new truck has something like a 120K mile coolant interval.
Lots of newer cars with oil quality meters will run engine oil to 15-20K before changing.
Dangerous_Echidna229@reddit
That’s not running forever like you said.
updatelee@reddit
I top them up when they need to topped up. I replace the fluid as per the service interval.
revocer@reddit
Check levels and Top off all fluids as necessary every oil change.
Never flush.
BUT do drain and fill as recommended by the owners manual.
If CVT transmission. Change fluids every 20-30K miles.
If automatic or manual. Change fluids every 50-60K miles.
Dangerous_Echidna229@reddit
How about engine oil?
Blu_yello_husky@reddit
I only check my fluids if a dummy light comes on or something starts acting up. Otherwise I just drive it and don't worry about it
Dangerous_Echidna229@reddit
Dangerous and expensive attitude!
Mxer4life38@reddit
Transmission fluid in an automatic transmission is one of those things that you either change every 30k miles or when it's finally time to rebuild it (aka never).
Coolant I like to change mine every 50k miles. Power steering fluid I don't think I've ever changed it unless it's necessary. Brake fluid I'll change it whenever I put new pads on, if the pedal starts feeling squishy, or if it starts turning dark (it should be clear, yellow isn't optimal but I wouldn't stress if it is).
Topping off the fluids is more about frequent checks. Every 1-4 weeks you should check the levels of everything. Takes a few minutes of your time but it's a good habit to get into. If you notice something getting low frequently then you should check it more like every week. If brake fluid gets low frequently then I'd consider it an emergency and you should get to a shop ASAP to diagnose the issue. A brake leak on 1 corner will significantly compromise the braking power on all 4 corners.
Practical_Card5032@reddit (OP)
That makes sense. Let's say my coolant is low (which is not), would that mean there is a possible leak and I shouldn't just top it off?
Dangerous_Echidna229@reddit
Yes there may be a leak.
Putrid_Knee_995@reddit
coolant is a pretty quick but major one to keep track of. I typically check mine once a week, in reservoir and cold rad. This will also catch a failing rad cap.
I drive a 33 year old car that I've basically rebuilt atp. So my frequency of checks is a little neurotic.
Mxer4life38@reddit
Yes that indicates a leak. There are A LOT of reasons why coolant would go low and usually they aren't horrific. So I wouldn't freak immediately unless the reason you discovered it is because of an overheat. But it should be addressed soon after discovery regardless of severity.
MidwestMan43@reddit
This isn't the full truth. Coolant DOES evaporate over time. Of course, at a slow rate. it shouldn't be disappearing at a noticeable rate, but let's say you haven't changed the coolant in a few years, the level is likely going to be lower than when it was filled last. Especially when the water concentration in the coolant is high. A top-off of the coolant every once in awhile is normal maintenance and not necessarily a sign of a leak.
Mxer4life38@reddit
Yes! Thankyou for that clarification.
Mxer4life38@reddit
I'm also going to add. If you are unsure about something's severity, assume the worst. Best to assume that than to break your car more.
TheFragileRich@reddit
You generally shouldn't have to top off fluids, that is a sign of a mechanical problem.
With brake and coolant it is generally every five years as rule of thumb but it will obviously vary by car and driving conditions.
Also, people generally add washer fluid as needed. It takes like 30 seconds.
Practical_Card5032@reddit (OP)
Okay that's what I figured. I never top off fluids and my car runs just fine without any mechanical problem. I was just concerned since I never addressed the fluids and if it'll be a bigger problem later on. But thanks for the clarification.
HotmailsInYourArea@reddit
You need to check the levels occasionally though, as you could spring a leak. Also it’s not abnormal for an older car to burn some engine oil, I’d check the level every fill-up until you know if your car consumes it or not.
Dangerous_Echidna229@reddit
New cars burn some oil too, some more, some less.
Dangerous_Echidna229@reddit
Don’t forget to check engine oil level often.
Dangerous_Echidna229@reddit
Look at your engine oil level.
RelevantMarket8771@reddit
If you live somewhere with bugs and pollen, washer fluid gets drained very fast.
nips927@reddit
Everything varies based on the car or truck and driving conditions or weather. We are going to use my truck as the example. 2020 Ford ranger crew cab 4x4 2.3L direct injection turbo charged.
Engine Oil, I check monthly especially more so when seasons change or if I'm getting close to an oil change. Because of the type of driving I do, i spread oil changes out, if you do a lot of hwy miles like myself roughly 30k-40k hwy miles a year, I do my oil changes every 7k-8k miles otherwise I'd be changing it every month. Generally when my oil smells like gas is when it's time to change.
Washer fluid usually when my light comes on my dash or I get a notification in my app.
Coolant I check it when I check the oil. Or refill my washer fluid. My coolant has a hot/cold mark on the reservoir. Should be noted that just because it's low when it's cold doesn't mean theres an issue, just means the coolant shrank when it cooled back down all fluids expand when they get hot.
Brake fluid i check but never refill, I know my pads are starting to wear and that mark on the in brake fluid tells me how much brake pad life I have left. Never refill your brake reservoir unless you loose your brakes and you need to get off the road or if you're flushing/bleeding the system.
Transmission, alot of newer cars and trucks, like my truck doesn't have an easily accessible dip stick, have to go under my truck on the passenger side, and theres a small dipstick, oh btw it's next to the fucking exhaust. There's no trans plug either if you have to drain it you are dropping the pan.
Differentials, it's a good habit to check it at least once a year more frequently if you tow a lot, and top off the fluid it will evaporate and breath
Transfer case if it has it, should be checked at least once a year more so if you use 4x4 frequently.
Power steering, I don't have power steering reservoir so I wouldn't know. New cars usually don't. My wife's car doesn't, my truck doesn't, and my focus doesn't.
If you have a manual transmission usually the slave cylinder(clutch master cylinder) is tied together with the brake master cylinder.
Fluffy-Cupcake9943@reddit
You should never top off brake fluid unless you are bleeding the system. The fluid level goes down as the brake pads wear and goes back up when you replace the pads. If the fluid is low, check your brakes.
Waste-Menu-1910@reddit
Top offs are for people who have decided that excess fluid consumption is more affordable than fixing the problem. In some cases it makes sense. If you have to add a little oil between changes, compared to the cost of replacing a hard to get to seal, nobody can say you're wrong.
But if your vehicle is in good mechanical condition, you're not typing off anything. You're replacing fluids on manufacturer scheduled intervals.
Since topping off is something you only do to overcome wear or delay repairs, intervals will vary based on individual cars
Dry-Discipline-2525@reddit
It depends a bit on the vehicle. In general, all fluids need to be completely changed after a while and the exact interval will depend on the car and the specifics of the fluid used. For example, conventional oil usually needs to be changed more frequently than synthetic oil.
General rule of thumb for changing fluids:
Engine oil: Every 5,000 miles, 12 months, or when it gets too dirty. Whichever comes first
Brake fluid: Every 2-3 years
Transmission fluid: Highly dependent on the vehicle but take 60-120k miles as a ballpark. Some sealed automatic transmissions will say that the fluid never needs to be changed which is a lie, it lasts "the life of the vehicle" which is when the manufacturer's warranty expires.
Power steering fluid: 75k miles or 5 years, whichever comes first
Engine coolant: 50k miles or 3 years.
Differential/gear oil: 60k miles. Similar to transmission fluid, some of these will claim to last for the life of the car and need to be changed regularly after the manufacturer's warranty expires.
You should check your fluids regularly, monthly is pretty safe for a reliable car. Weekly if your car is a trouble maker. Just checking the basic fluids whenever you get gas is an easy routine to follow too.
Always keep your fluids in the appropriate zone between changes/flushes. The reservoirs should have gauges or dipsticks. Some should only be added to a cold engine. A lot of transmissions do not have an easy way to check fluid level and just need to be changed when it is time to do so.
You also usually don't need to completely flush anything beside your brakes when changing fluid. Brakes should be flushed to ensure no old fluid is in there and it's not a bad idea with other systems like coolant and power steering but it ain't life or death.
Always refer to your owner's manual or Hayne's repair guide if you are unsure about something.
TL;DR: See your owner's manual.
DisastrousAnt4454@reddit
Would I find blinker fluid intervals in my manual as well
Dry-Discipline-2525@reddit
That actually needs to be changed daily or your car could explode.
DudeWhereIsMyDuduk@reddit
Both diffs - 30K unless underwater (haven't extended the breathers yet) Transmission/transfer case - 50K Oil/filter - 5K, full synthetic Brake fluid - 2 years
jolle75@reddit
Brake fluid should not be topped off. If it’s to low, change pads and flush the system (should be done every other two years at least).
Steering fluid should not get any lower. It would mean you have a leak
Transmission oil should be enough for between services (usually around 70.000 km for modern manuals)
Coolend should be ok between service intervals. If it drops, something is wrong
Engine oil: when the engine is new or just rebuild, it could take a bit, but with normal use, it should be ok between service intervals. Else: something is wrong
Windshield: for when you used it up :P
dudeman618@reddit
Check them.often in a car you just purchased, new or used, you'll need to see if anything is leaking or burning. Newer cars have have sensors on just about everything but it's still good to check everything yourself until you find nothing is leaking.
I had an old truck with well over 200,000 miles and did not drive it often, it leaked oil so I had to add oil often. Brakes, power steering, and others I went months without checking. I had a newer vehicle and everything is digital so I don't check often and nothing leaks.
s1lentlasagna@reddit
You should never have to top off anything, if you do then you have a problem. You should be checking fluid levels and making sure they are not leaking.
Ill_Mix8088@reddit
My 2007 impala LS4 5.3 twice a week I top it off for oil. My 2021 Mach 1 once every 3 months might slightly less oil than full mark .
My LS4 leaks small amounts of oil must be a LS thing .
375InStroke@reddit
Fluids don't suddenly disappear. I have four cars over 55 years old. I know some use more oil, or leak more transmission fluid than others, so it's like Jesus tells me to check this or that more often on some cars than others. When you're waiting for gas to fill up is the traditional time to look under the hood. If you check your car's oil every time you get gas, and it doesn't move, then you shouldn't have to check it so often. If you notice a puddle under the car when you pull out of a parking space, or collecting under where you park it at home, then that should be a clue that you should investigate, right? Most cars these days have a clear brake reservoir that you can easily check visually. Same with coolant.
OpinionExisting3306@reddit
Check them often. Weekly for engine oil. Monthly for everything else. Top them off as needed. Change them according to your owner’s manual maintenance schedule. Keep in mind that all of these fluids (except washer fluid) are in closed systems and should not need topping off too often. For most fluids consumption = problem.
Practical_Card5032@reddit (OP)
Got it. So fluids such as transmission, powering steering, brake fluids should be monitored, but not necessarily topped off?
Off topic but if my coolant is low (which is not), would that mean there is a possible leak and I shouldn't just top it off?
Familiar-Seat-1690@reddit
Brakes \ power steering. Try not to open too often. They are both fluids that can absorb water from the air degrading them. I check these spring and fall unless I can see through container visually.
washer - I do every stop for gas. Bugs in summer and salt in winter uses lots of fluid.
transmission and diff fluid - every 2-3 years if no dip stick.
coolant - I can see level without opening.
oil and tire pressure . Monthly or so.
DEF fluid - no idea here never owned a diesel
OpinionExisting3306@reddit
Absolutely top it off if it’s low. Just be aware that if you have to add fluid, that usually means something is wrong.
Practical_Card5032@reddit (OP)
Thanks, I'll definitely look into this!
branch397@reddit
Older cars (and maybe newer ones, I wouldn't know about them...) have brake cylinders that will rust because brake fluid absorbs moisture from the air. An interesting issue that I've read about is that if you don't bleed your brakes for a few years, rust will build up in the master cylinder at the point just past where the piston stops when you apply brakes. So, when you bleed and push the piston all the way in, this rust can damage the seal. I don't know if this is an exaggeration, because I bleed my brakes yearly, meaning I pump until the master is almost empty, refill, repeat. Also, six months later I use a vacuum pump to empty the master cylinder and fill it with fresh fluid.
ContributionDry2252@reddit
Checking engine oil regularly, and topping off if low - but then I'd get the engine checked, there might be a problem.
Transmission oil .... something I've never had checked, and the car is soon of drinking age ;)
Washer, fill up when emptying.
Others, annual maintenance takes care of those.
Affectionate-Box2768@reddit
Top off….as needed. Flush and fill every two years. Transmission, differentials by mileage.
Galopigos@reddit
The only one you would normally top off would be the washer fluid. Unless you are completely changing them or you have a leak the others are just checked for level. The brake fluid can show you brake wear, if it's low, check the pads for wear. Beyond that there is no "topping up" So check the engine oil, add if the engine uses oil or leaks. Check coolant level, Check transmission level (if possible, many newer vehicles this is a real pain to do as they don't have dipsticks) Power steering for level.
For fluid changes it depends, For brakes I generally use a power bleeder then follow the same process as bleeding them. Power steering I'll pull as much as possible out of the reservoir with an extractor, then fill it and disconnect the return line. Then have someone start the engine while I aim the return line into the waste oil. Then keep adding until the fluid comes out clean. Coolant gets a drop, then fill with water and a cleaner, let that run a bit, then drop that out, flush with clean water then fill with the proper coolant.