Fluid changes necessary so often?

[bononos]

http://www.freerepublic.com/focus/chat/3074898/posts
http://autos.aol.com/article/fluid-flush-fallacy/

Are 10k oil changes alright or are car manufacturers fiddling around with the numbers to lower the cost of ownership on paper to be more attractive to customers? And is letting power steering fluid become dirty alright instead of changing it like the article says?

 

[leper84]

10k changes on blend oil make me a little nervous. I do think manufacturers over extend or even omit service recommendations to lower cost of ownership. Most people trade in at 60-100k miles, they could give a crap what happens after that if it isn't fleet use.

On a good blend oil I think 5-7k miles is plenty reasonable, anything more I'd say synthetic.

As far as the articles you linked, the AOL one is spot on. The Free Republic one is full of s***.

 

[996GT2]

10k changes on full synthetic are perfectly fine. 5-6k miles on modern dino oil would also be fine.

That article has a lot of inaccuracies in it, though.

For example:

Brake Fluid Flush – Brake fluid is hydrophillic, which means it sucks up water like a thirsty camel. Brake fluid can even pull water out of the humidity in the air. As brake fluid sucks up moisture, it loses effectiveness. If it absorbs enough water, brake fluid can even “boil over” during normal use.

In light of brake fluid’s sensitivity to water, automakers go to great lengths to ensure your brake system is completely and totally sealed. Therefore, the average vehicle never needs replacement brake fluid. Unless you’re doing a LOT of heavy braking (racing, towing a heavy trailer on a regular basis, etc.), your brake fluid will last as long as the system remains sealed. It’s almost always unnecessary to flush brake fluid.

This is simply untrue. Brake fluid needs to be flushed every 3-4 years or ABS and other brake components will be at risk of premature failure. It's MUCH less expensive to do a few brake fluid flushes than it is to replace ABS components.

 

[Pacfanweb]

Any fluid that had contaminants or wear particles that get in it needs to be changed.

Engine oil's worst enemy is combustion byproducts.

Power steering fluid...if it turns black, what do people think is happening? It's contaminated, and isn't the same fluid it started out as.

Same with all other fluids.

I do believe that manufacturers have gone a bit high on some of the intervals....I've seen 100k on transmission fluid....that is too much.

 

[bononos]

Newer cars have synthetics as their stock replacement engine oil and lengthened their change intervals to 7.5-10k. Its significantly more expensive to replace synthetic oil just every 3-5k.

I thought of cutting down engine oil changes in half by just changing the filter every other time when the new synthetics like Mobil1 came out. But the thought of having to manage engine oil jetting out after unscrewing the filter dissuaded me.

 

[BUTCH1]

10k changes on full synthetic are perfectly fine. 5-6k miles on modern dino oil would also be fine.

That article has a lot of inaccuracies in it, though.

For example:


This is simply untrue. Brake fluid needs to be flushed every 3-4 years or ABS and other brake components will be at risk of premature failure. It's MUCH less expensive to do a few brake fluid flushes than it is to replace ABS components.

110% agree, if you lie in a humid area (I'm in FL) I flush every 3 years or if I'm changing pads I flush as well and every time the fluid has a dark, nasty look to it, I can't explain how it happens but the humidity DOES manage to find a way in there.

 

[996GT2]

110% agree, if you lie in a humid area (I'm in FL) I flush every 3 years or if I'm changing pads I flush as well and every time the fluid has a dark, nasty look to it, I can't explain how it happens but the humidity DOES manage to find a way in there.

Brake systems are never 100% sealed. Humidity will find its way in there eventually.

The other thing about brake fluid is that it's one of the few things which actually DO need to be flushed. For things like transmission fluid, drain and refill is the preferred method for many manufacturers (especially Honda), but for brakes, there is very little circulation of the fluid, so if you just drain the fluid from the reservoir and re-fill, none of the old fluid in the lines is actually being changed.

The only cars which technically do not require brake fluid flushes are those using DOT 5 (silicone based) brake fluid, but IIRC that's pretty rare.

 

[BUTCH1]

Brake systems are never 100% sealed. Humidity will find its way in there eventually.

The other thing about brake fluid is that it's one of the few things which actually DO need to be flushed. For things like transmission fluid, drain and refill is the preferred method for many manufacturers (especially Honda), but for brakes, there is very little circulation of the fluid, so if you just drain the fluid from the reservoir and re-fill, none of the old fluid in the lines is actually being changed.

The only cars which technically do not require brake fluid flushes are those using DOT 5 (silicone based) brake fluid, but IIRC that's pretty rare.

Yup, I actually flush BEFORE I change pads because compressing the calipers piston will force dirty fluid upstream at the ABS, first I remove all the fluid in the master cylinder, re-fill with new then flush by attaching a piece of clean tubing to the bleeder screw and the other end to one of those medical syringe's that hold about 3-4 ounces, crack the screw as you apply suction then close screw as syringe is about 3/4% full, remove tubing from bleeder and push it out of the syringe into a small bottle, replace back on bleeder screw and repeat until clean fluid comes out, (monitoring the master cylinder of course, you DON'T want any air in the ABS). Works well enough and it's a cheap setup, pressure bleeders are the cats meow in this area but since this is a once in 3 years event I don't want to spend the $$ for one..

 

[bryanl]

The only way to know is by having the used fluids tested by a company like Blackstone Labs.

 

[kitatech]

I don't think there's anything that has more universal impact (effecting performance of more parts than than the fluids' own function) on engine and mechanical performance and longevity, and cost less per mile to "maintain" than fluids...plugs and the PCV valve are also cheap maintenance per mile, but their impact is less broad than fluids...