Other than engine/****** oil, do you change your fluids?

[babzog]

Recent thread on anti-freeze has got me wondering... do you guys change your "other" fluids regularly (or ever)? Coolant, brake, PS are the three that come to mind (that are on my car, anyway). Since these appear to be closed systems, is there really a reason to change the fluids?

 

[klutz]

Brake fluid is one of those things that gets overlooked, if your fluid turns dark in colour it may be time to swap it out with some new stuff... I just did mine after 3 years of just topping it up. Same idea goes with power steering... the fluid molicules will actually break down and not be as affective. Diffs and transfer cases are among others that get forgotten about. After 200,000 miles or more, your vehicle sure won't hate you for changing these. And "some" would advise LUCAS additives as well.

p.s. theres always a possibility for water entry, and condensation in these parts also.

Hope that sheds some light.

 

[Frank Elson]

I change every fluid asap on a new-to-me vehicle. Then I have a known starting point.
Then, everything else gets changed at two year intervals "whether it needs it or not".
Fluids, filters etc are so cheap, compared with the total price of a car ... and no mechanical item will ever be upset at having all new fluids.

 

[Titus]

Engine Oil- every 3k miles, or before a track event if it is more than 1500 miles old.
Transmission & Diff- Annually
Brake & clutch fluid- Annually
Coolant- every other year
Power Steering fluid- top off if needed, but have never flushed it.

 

[benjamming]

coolant - drain & refill (5 quarts) every 30k on '02 Accord; 94 Grand Am 3.1L whenever the LIM gaskets leak it gets changed of course ha!
brake fluid - flush at every pad change
power steering - drain & refill the reservoir every 30k miles
transmission depends upon the vehicle.

 

[Mike83]

I've done everything except brake fluid. As far as I'm concerned, the brakes aren't squishy and more likely than not I'd make things worse by trying to bleed them.

 

[pattenp]

I try to change all fluids as called for in the maintenance schedule. The coolant and brake fluid sometimes goes longer than called for. Trans, oil and diff I do on schedule.

 

[GN4WHLN]

Axels, transmission, transfer case, coolant, brake, PS fluids changed every two years.

 

[adam728]

Brake fluid is often overlooked, but is hydroscopic, meaning it will absorb and hold water from the air. Over time it will pull moisture from the master cylinder resivoir, where it will contaminate all the fluid. Whenever I change pads I use a cheapo vacuum bleeder to pull fresh fluid thru the whole system.

When I used to do lots of off-road mudding I'd often change diff, transmission, and transfer case oil literally every month. Seems like that's about how often the truck was being left buried in waist deep water.

Don't forget to change your blinker fluid too.

 

[Torque1st]

I watch the color of the coolant and change it if it starts to turn brown. I add corrosion inhibitor concentrate every 3 years. If I have added any cooling system leak inhibitor then I change coolant every three years. Leak inhibitor seems to be needed on the Ford 4.0L V-6.

Engine oil every 5K or annually on low mileage vehicles.

PS oil only if a part needs to be changed. At that point I add an inline PS filter.

Transmission, every 75K and I use an inline filter as above.

Differential, never unless repairs are needed.

Brakes, only if calipers or wheel cylinders are replaced.

 

[Keep]

I change every fluid asap on a new-to-me vehicle. Then I have a known starting point.
Then, everything else gets changed at two year intervals "whether it needs it or not".
Fluids, filters etc are so cheap, compared with the total price of a car ... and no mechanical item will ever be upset at having all new fluids.

This is pretty much my regiment as well.

Only other time is if I go trail running and hit some really deep water, then I will check/change the rear diff fluid as well, as it usually gets some water down the vent tube.

 

[djd99]

I've done everything except brake fluid. As far as I'm concerned, the brakes aren't squishy and more likely than not I'd make things worse by trying to bleed them.

Exactly what I was thinking especially on late model cars as some need to be bleed electronically you may open a can of worms, this is one fluid ment to last long term.

 

[Fast Orange]

Engine Oil-Mobil1-5-7000 miles-New K&N oilfilter with change
****** fluid-Amsoil-25000 miles with Fram filter-no convertor drain
Brake Fluid-DOT4-2 Years or hydraulic component replacement
Coolant-Every three years-60% Prestone,40% tap water-full flush,add corrosion
inhibitor
Trans Case,Diffs-every 50000 miles,unless dunked(VERY rare) Amsoil Fluids
This regimen has worked well on the last 2 trucks I've owned-253,000 miles on my 79 F-150, 135,000 miles on my 97 Dodge.

 

[bigdav160]

Brake fluid long term? Not likely. It is so hygroscopic that it can pull water through the smallest of openings. I've had engineers tell me it will pull moisture through the rubber hoses but I have trouble believing that. Within a couple years your brake fluid is probably so saturated with water that the boiling point of the fluid is affected and corrosion has started.

Also, coolant can look great, have a nice low freeze point but still have a low pH that will start corroding the cooling system from the inside out.

 

[WSMC633]

On My Truck I just change everything at the Manuf. Maintenance Intervals. I just did the Rear Diff, and Transfer case a few months back. The ****** is a little over-Due, so I'll probably take care of that when I do the Oil in the next couple Weeks.

On My BMW I do the Brake Fluid every six Months, Coolant with Wetter every year, Oil Regularly. I follow the Maint. Schedule for everything Else.

On my Race Bike I do Water + Wetter every couple of months. Or if I have it apart it just gets changed. (Coolant is a big No-No on the Track!)
Oil every Race weekend or every 2 track days
Brake Fluid every couple Months.
For Me the Constant Maintenance on the Bike keeps everything else in tip-top shape.

 

[Torque1st]

I've had engineers tell me it will pull moisture through the rubber hoses but I have trouble believing that.

Water will migrate through many materials. Brake heat helps drive the moisture out of the fluid but it will not get it all.

Remember 100,000 miles is only about 2,200 hours of operation which is not much by industrial standards.

40 hrs/wk x52 weeks is 2,080 hours/yr.

24/7 is 8,760 hours/yr.

 

[e-tek]

Engine Oil- every 3k miles, or before a track event if it is more than 1500 miles old.
Transmission & Diff- Annually
Brake & clutch fluid- Annually
Coolant- every other year
Power Steering fluid- top off if needed, but have never flushed it.

coolant - drain & refill (5 quarts) every 30k on '02 Accord; 94 Grand Am 3.1L whenever the LIM gaskets leak it gets changed of course ha!
brake fluid - flush at every pad change
power steering - drain & refill the reservoir every 30k miles
transmission depends upon the vehicle.

I change every fluid asap on a new-to-me vehicle. Then I have a known starting point.
Then, everything else gets changed at two year intervals "whether it needs it or not".
Fluids, filters etc are so cheap, compared with the total price of a car ... and no mechanical item will ever be upset at having all new fluids.

You guys are so crazeeeee!!! (nuthin' personal!!)
There's little to no good evidence that changing all these fluids - "needed or not" - helps avoid repairs or increases longevity. I buy 30-50 year old cars that have original ******, diff and brake fluids - nothing wrong with them!

I watch the color of the coolant and change it if it starts to turn brown. I add corrosion inhibitor concentrate every 3 years. If I have added any cooling system leak inhibitor then I change coolant every three years. Leak inhibitor seems to be needed on the Ford 4.0L V-6.

Engine oil every 5K or annually on low mileage vehicles.

PS oil only if a part needs to be changed. At that point I add an inline PS filter.

Transmission, every 75K and I use an inline filter as above.

Differential, never unless repairs are needed.

Brakes, only if calipers or wheel cylinders are replaced.

Now Torque is at least REASONABLE ABOUT IT!

The only thing that benefits from "hyper-changing" your fluids - are the fluid companies...

 

[e-tek]

Brake fluid long term? Not likely. It is so hygroscopic that it can pull water through the smallest of openings. I've had engineers tell me it will pull moisture through the rubber hoses but I have trouble believing that. Within a couple years your brake fluid is probably so saturated with water that the boiling point of the fluid is affected and corrosion has started.

Also, coolant can look great, have a nice low freeze point but still have a low pH that will start corroding the cooling system from the inside out.

I totally agree with the coolant, as water is corrosive and we've all seen the results....but as for brake fluid, hygroscopy and corrosion, I've never seen a brake system fail from the inside out....

 

[Torque1st]

Engine oil must be changed because of combustion contaminants and other wear products.

Other automotive lubrication systems are cleaned and filled at the factory with clean filtered fluid. Unfortunately every time the fluid is checked or maintenance is performed contaminants are introduced into the system. The fluid in bottles and cans is extremely dirty. Unless you have some sort of good filtration in the system it is best to leave that factory fill in the PS, ******, or diff alone.

Here is a decent discussion on brake fluids:
http://www.afcoracing.com/tech_pages/fluid.shtml

 

[chadster1]

For power steering and brake fluid I will just **** the fluid out of the resevior using my Mityvac fluid evacuator. I then refill with new fluid. I know that actually flushing or bleeding the system would be more complete but this way I do not have to deal with opening the system in any way other than to resevior cap.

 

[babzog]

Interesting stuff and not at all out of line with what I've been thinking of late. I'm about 50k kms over my coolant change interval and have never changed (or had changed) the brake fluid. Mileage is about 241k kms on an '02 Civic. Was thinking I might drain and replace the coolant this weekend as it's also due for an oil change, which then got me thinking that no other fluids have been changed (engine and MT oils aside) since it was new.

Brakes aren't spongy and (as far as I know) the reservoir has never ben opened (you can see the level w/o opening it) so I'm not sure if I want to open that one up, but the recommended interval has long passed (twice, I think).

 

[hetkind]

I think I went 200k plus on the Toyota pickup without touching the brake fluid...went to bleed one day for a mushy brake and one of the bleed screws was solidily siezed. I had to swap out the wheel cylinder. Not too much of a problem for a common vehicle, but the BMW motorcycles NEED yearly brake flushes or else you will be replacing thousands of dollars of brake and clutch pieces.

Howard

 

[Titus]

You guys are so crazeeeee!!! (nuthin' personal!!)
There's little to no good evidence that changing all these fluids - "needed or not" - helps avoid repairs or increases longevity. I buy 30-50 year old cars that have original ******, diff and brake fluids - nothing wrong with them!



Now Torque is at least REASONABLE ABOUT IT!

The only thing that benefits from "hyper-changing" your fluids - are the fluid companies...

It all depends on the car and how it's used. The intervals I listed are for my supercharged Miata putting out more than twice its original HP that sees occasional track and autocross days. $40 in fluid and 90 minutes of my time each spring is cheap insurance. I follow the manufacturers recommendations for the wife's MINI Cooper.

 

[russlaferrera]

I totally agree with the coolant, as water is corrosive and we've all seen the results....but as for brake fluid, hygroscopy and corrosion, I've never seen a brake system fail from the inside out....

Try bleeding the m/cyl. The fluid will be dark brown to black. What about frozen w/cyl and calipers? gummy fluid? You bet! Only brake fluid I know of that lasts a long time is DOT5, which is silicone.

 

[benjamming]

e-tek,

I understand your points about my OCD. Remember though that more performance is being extracted from less in every part of the car. What worked 10, 20, etc. years ago is no guarantee that it will work now. I am thinking of transmission fluid here the most. Automatic transmissions are the weakest link in most vehicles now. The engines will typically outlast the AT.

Honda used to recommend changing the power steering fluid every 30k miles. This went away when everyone started trying to sell customers on no scheduled maintenance before 100k type stuff. You can look at BMW for more examples of "this is required" at one time but once BMW started picking up the maintenace for x miles, "no, that's overkill" now.

I think that I do understand the underlying principle you are trying to point out. For example, brakes used to be real simple & worked fine. Now, we have devolved into complicating it beyond belief with minimum real improvements.

High performance track-type cars excluded, of course, from the above diatribe.

 

[Boyd Who]

Yer sposed ta change da fluids??

 

[adam728]

Yea, hygroscopic, opps.

Water can diffuse thru rubber. Thickness, hardness, and other factors effect the rate. And yes, brake fluid definitely absorbs it. Like russlaferrera said, you can often find old fluid that is black or rusty.

And judging oil or coolant by how it "looks" doesn't mean anything. As others said, coolant's PH level can be way off base and it will still look fine. Transmission or differential oil viscosity can be greatly broken down by shearing of gears, yet it can still appear clean and fine. Engine oil can be contaminated with fuel bypassing rings (engine running too rich, too cold, bad rings, etc), and still look good.

You'll notice that although manufactures often brag "No maintance for 100,000 miles", there is always a second maintance schedule for "severe usage". Just quoting a Jeep manual, "severe" usage is considered:

• Frequent short trip driving less than 5 miles (8km)
• Frequent driving in dusty conditions
• Trailer Towing
• Extensive idling
• More than 50% of your driving is at sustained high speeds during hot weather, above 90F (32C)
• Off-road driving
• Desert operation

Any of these usages will basically have you changing fluids 3 times as often.

Stretching service intervals to save a few bucks is not doing your car any favors. Go talk to any mechanic and I'm sure they'll all have dozens of horror stories about problems caused by neglect.

 

[NUTTSGT]

I don't flush/change the brake fluid or P/S fluid but I do the oil/coolant/trans and rearend.

 

[Need4racin]

Yep I pretty muchly follow the normal maintenance guide in the user manual. But the newest vehicle I have is 14 years old.

Only time I change the brake fluid is if I have to replace a caliper, hose, wheel cylinder, etc.
Powersteering fluid gets changed when I swap out the whiny ford ps pump for a saginaw pump off a van.

 

[tcianci]

I'm more or less with e-tek here. As I stated in the Antifreeze thread, I have actually never changed coolant on any car. PS fluid, brake fluid, axle lube? Not a chance. Brake fluid absorbs water, thats right, but it's not like someone is under the hood hosing the master cylinder all day. I too have never seen any component of a hydraulic brake system fail from the inside out. I have never seen an axle fail from old lube either. There seems to be some pseudo-science behind some of the reasons for changing these fluids.
Every vehicle has a useful service life. What determines that life is different for every owner. Personally for me its when the body starts looking shabby. So If I had a ****** or engine problem and it was still a good solid car, I may just fix it or otherwise its off to the big pic-a-part. I would be interested to see what you guys think is a useful service life. I said it before and I'll stick to it... If you keep any lube at all in these systems...good, cheap, clean, dirty whatever, it's near to impossible to wear out an engine or ****** or axle these days.

 

[nate379]

I change everything. I don't have an interval on brakes, but I bleed out the master cylinder when I do brake work that involved opening the sytem if the fluid is nasty.

The way I look at it, fluids are usually cheap compared to replacing parts.

Useful service life is when the wheels fall off and then I will buy new wheels and put them back on.

My 98 Dodge 2500 has 200,000 miles and I plan on it lasting at least another 150,000-200,000.

 

[e-tek]

Most coolants have advertised 200,000-300,000 miles lifespan.....

As was said above, I think it has a lot to do with contamination. Engine oil is easily and quickly contaminated with ring bypass. But all other systems remain closed and likely don't need changing. I have gotten new cars from work every 2-3 years. They routinely have 100,000 miles on them when turned in - none have a scheduled ******/diff or coolant change.

But I can see changing fluids if doing repairs - often you have to drain X fluid to do the repair anyways, not to mention the contamination factor again.

 

[babzog]

Looked at the brake and clutch fluids last night. They were pretty brown in colour, so while I'm tempted to change it out, I also hear what other like e-tek are saying. I too have never had a brake system fail on me due to a fluid related issue. Or maybe I did but was never told that bad fluid was the cause (ie: internal corrosion leading to failure). A fella at work never changes his brake fluid and he runs his cars into the ground but the manual (for the Civic) says to change it every three years regardless of mileage.

Maybe a better question is: Is internal corrosion (presumably from contaminated fluid) a common cause of brake failure or is something else usually to blame (or is it darn near impossible to tell)?

Was thinking and I recalled that I only notice the pedal getting soft when I'm out playing with the car and working the brakes hard (ie: when breaking in new pads). Only then, the pedal gets very soft. Under normal use, it's fine. I'd not previously attributed that soft pedal to contamination but perhaps that's exactly what it is.

 

[benjamming]

Is brake failure even really that common (outside of the pictures we have all seen where the rotor is almost nonexistent, etc.)? Too much emphasis is placed on brake fluid change where caliper rebuild or wheel cylinder is what is really needed (which, of course, you would flush the brake fluid at that time).

 

[hetkind]

I have lost brake and clutch components from internal corrosion...plus once the gear oils change color due to condensation, wear or corrosion they get changed.

Think about it, you can change ALL the fluids on a vehicle for the cost of a single, simple radiator recoring...

And the idea that if the use opens a fill plug they will contanimate the system is a scare tactic. If you use clean fluids and tools then the old fluid comes out dirty and the new fluid goes in clean. It is not rocket science...

Howard

 

[mikeyr]

I am slightly weird on this, I change the fluids on my cars regularly, on schedule or more often than manufacturers schedule. But on my 1999 GMC truck, I have never changed anything but engine oil, still the original coolant, ****** oil, rear end oil, brake fluid, hoses, belts, etc.

Can't explain why I do all the regular work on my cars and my wifes car but not my truck, bought it new in 1999 and I have almost 65,000 miles on it now but its a lot of years for those fluids. Things still look good in it except the brake fluid is near black and yes I know that brake fluid is hydroscopic (spelling?) and attracts water which is bad and should be changed regularly.

But for all those saying never change the fluids (brakes especially) what do you consider a lifespan, for example my truck is 11 years old with barely 65,000 miles, I am well under when I need to be doing maintenance on it mileage wise but years wise I believe I am overdue. Its not just mileage that you need to consider its time as well. I have seen lots of brake failures from internal corrosion but it was on 70+ year old cars, not seen it on 20 years or less old cars.

Maybe I should start another thread about bleeding those brakes this weekend

 

[e-tek]

But for all those saying never change the fluids (brakes especially) what do you consider a lifespan

I hate to come off as CrAzY.....but in my experience - which includes 30 years of driving experience, working in bodyshops & new car dealers and now having restored many cars, I would think a car should "last" 15-20 years with the same brake, ****** and diff fruids. The only reason for those to be changed would be repairs in my book. I might change the AntiFreeze every 4 to 6 years - because whenever I've checked the freeze point that's how long it's generally lasted.

I wouldn't have a problem with any drive components puking after 15-20 years, but I've seen MANY cars go at least that long with the same fluids.

 

[nissan_crawler]

I hate to come off as CrAzY.....but in my experience - which includes 30 years of driving experience, working in bodyshops & new car dealers and now having restored many cars, I would think a car should "last" 15-20 years with the same brake, ****** and diff fruids. The only reason for those to be changed would be repairs in my book. I might change the AntiFreeze every 4 to 6 years - because whenever I've checked the freeze point that's how long it's generally lasted.

I wouldn't have a problem with any drive components puking after 15-20 years, but I've seen MANY cars go at least that long with the same fluids.

I've replaced a fair amount of brake components that were pitted from corrosion inside, forget honing with the shape they were in. Oh, and many of these components were "working" but damaged. That's just waiting for a failure to happen. That's like leaving a termite ridden floor joist alone. hey, it's holding the house up right now, why fix it?

Go take apart a wheel cylinder, or caliper on one of your old cars, I would be surprised if you didn't find pitting from corrosion. Just because they're working and not leaking at the time doesn't mean they're "right". I bet 50% of the ones I've torn down have been damaged.

Diff fluid, yep, it breaks down. Yep, you'll burn them up if it does. I ripped a pinion right off a 14 bolt chevy for that reason. It was used for heaby towing, wasn't changed for 140,000 miles. Oops. With the increased tow ratings of today's pickups, many manufacturers are spec'ing 75-140 synthetic, AND implementing more frequent change intervals. The heat kills the fluid. Racing, same way. The 75-90 I ran in the race car got freaking nasty 1/2 way through a season.

****** fluid carries wear debris, why let it go around and around and around? Even on manuals, I've noticed a remarkable difference in ease of shifting, just with a simple drain/fill. Obviously, something wasn't what it used to be.

I just bought all amsoil synthetic fluids for the crawler I'm building, both diffs, ******, t-case, engine, brakes, power steering. I also bought gear lube for the titan. It cost me $250. Almost any of those components that might fail from improper lubrication will cost me more than that. It's just cheap insurance to me.

If you really want to check, get an infrared gun. Go on a long drive, check the diff and ****** temp, then change the fluids and do it again. I did, the ****** wasn't as big, but the diff temp dropped 15*, and it was 10* warmer out that day, and I had more of a load. Again, the old lube obviously wasn't quite right anymore.

You can call it overkill, I'll call it cheap insurance.

 

[mikeyr]

Not coming across as crazy E-Tek, I am in the same range of years as well for the working lifetime of a car, after that it becomes an occasional driver. As I am about to change all the fluids on my truck this weekend, I guess I am in the 10 year mark for fluid changes, at least brakes. And I checked last night, 67,000 miles.