Mechanic’s Tale: The Flushing of America - PeachParts Mercedes-Benz Forum

haasman · #1 04-18-2006, 01:42 AM

Interesting ......BTW, I am not suggesting that anyone deviate from Mercedes' recommended maintenance..... simply an interesting article.

Haasman

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Source: TheCarConnection.com

Mechanic’s Tale: The Flushing of America
Just a Nightline away from scandal.
by Douglas Flint
(2006-04-17)

"If you take your car to a shop for a routine oil change you have a high probability of being told your car needs one or more of its critical fluids flushed, changed, or serviced. This started originally at the quick-lube shops and spread to the whole auto repair industry, including the dealers.

Part of the reason is technology. New machines have made it possible in most cases to change the fluids quickly and easily, or so the sellers of the machines say. But the real driving force is profitability.

Today I'm changing a timing belt and water pump on a Dodge Caravan. It will take all of five hours of bay time, a lot of parts and a lot of potential liability. In half the time I could do a series of flushes with little effort or liability and make much more profit. Since most people, mechanics and shop owners included, respond to economic incentives, it is coming to pass that every car going to every shop needs every fluid flushed every day.

In short, what is really being flushed is your wallet. It is straining the credibility of an industry that rightly or wrongly has always had credibility problems.

The four flushes

Old-timers from the Fifties, Sixties, and Seventies always knew it was a good idea to periodically drain the radiator, put a bottle of flush chemical and water in, run it a half-hour then wash it out again with plain water before refilling it with the proper mix of antifreeze and distilled water. Or if you wanted to do a really nice job you could cut one of those plastic flush tees from a Prestone flush kit into the heater hose, allowing you to hook a garden hose up and run a continuous flush.

Now these old-timers are being told their transmission fluid, power steering fluid, and who knows what else must be flushed on a yearly, monthly, or even daily regimen. Strangely, their '77 Olds Cutlass managed to run 180,000 miles without all this attention.

Now don't get me wrong. I am in favor of changing most fluids at 30, 60, and 90,000-mile intervals, regardless of what the owner's manual says. But that is not what's happening. These services are being oversold to a degree that is bound to damage the reputation of our industry to the net result that consumers will not believe any of us, even when we are telling the truth.

The run-down

Let's start with the automatic transmission - the most frequently flushed fluid besides the radiator. The advent of the transmission fluid exchange machine was a great step. In the past, automatic transmission fluid could only be changed by removing the transmission oil pan, which only holds three to six of the eight to ten quarts in the transmission. The second you started the car, the new fluid mixed with the old, eliminating much of the benefit of the service.

The fluid exchange machine, which some people choose to call a flush machine, cuts into the transmission cooler line at the radiator. As the car runs, old fluid goes out into the waste tank while new fluid is simultaneously pumped in. If the shop is really thorough, the car is lifted and actually driven through all the gears while the exchange is taking place. And if the service is done properly, the transmission oil pan still has to be removed and cleaned and the filter replaced - a solid hour and a half of work. So if a quick-lube shop is offering it to you in 35 minutes, something's not being done.

Now, as to checking the dipstick for color or smell to determine if your fluid needs to be changed. At the extremes (not changed for 100,000 miles or changed yesterday), you can tell. But as far as whether it was changed 3000 miles ago or 20,000 miles ago, no one can know, and if they say they can, they are lying.

Power steering fluid in general is not listed in most maintenance schedules as needing periodic replacement, although there are some exceptions. But we have a machine for that now too, so expect to be told you need your power steering fluid flushed. Look, if every three to five years (45,000 to 60,000 miles) you change your power steering fluid, that's not a bad idea. And replacing it with synthetic fluid, if allowable, is even better. But you certainly don't need to do it yearly or even every two years.

Brake fluid lives in a sealed environment because exposure to moisture will ruin it. No one ever dreamed of messing with it until Hondas became popular, and Honda for some reason does call for brake fluid replacement. Now we have (you guessed it), a brake fluid flush machine. If your factory manual calls for it, by all means, change your brake fluid. Other than that, leave it alone unless you are having brake repairs done, in which case changing it may not only make sense but be necessary if the hydraulic system has been compromised.

It is not enough that you are changing your oil every 3000 miles. Now when you go for your oil change they want to hook up a motor flush machine to clean your oil system out. Strange, my '63 Valiant didn't need that. Look, this goes under the category "If you need it, it won't help" - and thus sales are being encouraged on vehicles that really don't need it. If an oil system is dirty enough to have deposits of sludge forming, you're only going to get the sludge out by removing the valve covers and oil pan and scraping it out. Any stirring up of the stuff without removing it is likely to do more harm than good.

Stocking stuffers

I had an oil-change guy who lasted about a month. Every time a truck or sport-utility vehicle came in (the only vehicles left with a classic differential), he would call me over, waving his finger at me after having dipped it in the differential oil, saying "it needs a differential service," as if he who barely knew how to open a hood would know. Evidently it was a service heavily pushed at his last place of employ.

On a military 6x6 doing heavy duty in Iraq , differential oil needs constant attention. On a domestic SUV whose only off-road experience is driving onto the grass at the soccer field, just follow the owner's manual or change the fluid every 60,000 miles. The exception would be if you tow things or if you submerge the differential by backing a boat into the water.

Oh, and the transfer case fluid need only be changed at the required mileage or 60,000 miles.

Avoid the wallet flush

The easiest way to avoid having your wallet flushed is to try to stay with one shop that you trust, and keep good records. Now I know that even my best customers occasionally go elsewhere for an oil change when my shop is not convenient. So if you find yourself in a strange shop being told that the very lives of your children depend on your getting a particular service at that moment, just walk away.

Well, actually, that would be a tough one. But a new customer is often viewed as fresh meat, since all their existing customers have been flushed into the next galaxy. The harder the sell, the more you must resist. And believe me, the sell can be pretty rough. They can come at you with test tubes of fluid samples, and with pH strips whose color change indicates you are seconds from disaster (all provided by the flush machine manufacturers). Even my sister-in-law, whose toughness and command of Arabic swear words sent Egyptian border guards scurrying for cover, succumbed once.

And to the people in my industry, the owners and shop managers, I say, "What is it going to take? Another 60 Minutes or Nightline exposé where they go shop to shop and find out how many flushes they need after chemically certifying the fluids as new? Do you know how tough business is gonna be after that happens? Try thinking a little farther ahead than next week's bonus check."

Doug Flint owns and operates Tune-Up Technology, a garage in Alexandria, Va.

rchase · #2 04-18-2006, 02:35 AM

I have to agree the oil change places are sometimes pretty bad. They always are trying to sell services that are not needed. I find that they are good for a quick oil change without having to set an appointment with the mechanic.

If you go in and are able to tell them a lot of information about your car they tend to leave you alone. When they ask "what kind of engine do you have" (they are looking for the 6cyl 4cyl 8cyl info for their computer) the best answer is "This car has the OM617 5 cylender turbodiesel". When they have a customer that know's their car in and out their ability to lie and be deceptive is very much compromised. Most of them won't go through the trouble with me but end up dinging me for the extra oil that my car takes. If you look at the fine print "on the wall" only a certain amount of oil is included for free. I honestly don't mind paying extra for the oil and most of the time bring my own. The ones you need to avoid are the ones that blanket charge extra for BMW and Mercedes. If you see that on the wall run back into the bay quickly and tell them to stop before they start work. There is absolutely no difference between a Chevy or Mercedes when it comes to changing the oil.

These guys are trained to smell blood in the water so don't cave into their lies. If they detect any lack of knowledge on your end they go in for the kill and many times suggest your car barely made it in and do a hard sell claiming you won't make it out of the service bay let alone down the street.

Whats even worse than the oil change places are the brake places. They use all sorts of scare tactics and even quote "laws" about caliper thickness that don't exist. Many of them will pull apart your brakes and then try to sell you extra services and "refuse" to put your car back together unsafely to sucker you into repairs. Of course most self respecting Mercedes Owners should avoid "tune up clinics" and any Brake places like the plague. They know nothing of the special features of the engine and braking systems and do substandard work.

lee polowczuk · #3 04-18-2006, 08:58 AM

the only new vehicle that i have ever owned is a 1998 ford expedition. So it is the only car that has been under my direct care its entire span.

At 148k miles, it has been almost mechanically perfect. (changed a idle air control valve... should have cleaned it instead).

I change oil at 3k, tranny fluid at 30k and exchange brake, power steering, and radiator every two years. The differential is sealed supposedly.

perhaps just a coincidence, but i have never had a near perfect car. of the 4 benzes i have owned, all seemed to develop some sort of leaks.

rchase · #4 04-18-2006, 10:29 AM

Hmmm,

Consider the age difference on your Benz's. 10 years is a long time for rubber to deteriorate! Did you buy the Benz's new? I bet they were just as trouble free for their original owners 10 years ago.

Hatterasguy · #5 04-18-2006, 10:42 AM

A lot of people just don't know and get oversold on this stuff. Well at least other then costing you money it doesn't hurt the car.

I don't agree with him on the brake fluid part though, it should be changed every 1-2 years.

Mike Murrell · #6 04-18-2006, 11:03 AM

Quote:

Originally Posted by Hatterasguy

Well at least other then costing you money it doesn't hurt the car.

That's assuming the work was done correctly. It's scary how many shops, be it dealership, independent; chain cannot do a simple oil change correctly. I would imagine this same group would do no better at changing coolant, tranny fluid, etc.

On a side note, I find it interesting that many Toyota dealerships are now telling their customers that oil only needs to be changed every 5K. I wonder if the environmentalists are behind this?

Hatterasguy · #7 04-18-2006, 11:04 AM

Correct I am assuming they are half way decent shops, but thats a catch 22 since the decent shops usually don't pull this BS.

Since most cars these days use synthetic oil 5k miles is a good conservative number to change it. Actualy most manuals spec 7,500 miles for "severe duty".

Mike Murrell · #8 04-18-2006, 11:10 AM

Quote:

Originally Posted by Hatterasguy

Since most cars these days use synthetic oil 5k miles is a good conservative number to change it.

In my stable is a 2004 Toyota Tacoma base model pickup. Better half just bought a 2006 Toyota Avalon. Neither owners manual calls for synthetic oil.

All the Toyota dealers in my area(5 of them) still use conventional oil.

From what I've been able to come up with, Toyota is one mfg. who hasn't bought into the synthetic BS.

hughet · #9 04-18-2006, 12:47 PM

I just traded in a 95 Dodge Grand Caravan with 235K miles on it. I bought it new in January 95 for $23,000 tax and all. The owner's manual for the van said that I would only have to change the transmission fluid every 60,000 miles if the vehicle was subjected to "severe use"...otherwise the fluid was good for "life". I decided that the maintence intervals suggested by the smart guys who wrote the book did not make any sense to me and embarked on a program where I changed the oil every 5k miles with synthetic oil and all other fluids at 25k miles.

There is no plug on the torque converter like a Mercedes so when you change the transaxle fluid on a Minivan you have dropped the pan and changed the filter and replaced the pan you disconnect the transmission oil cooler line from the cooler and connect it to a clear plastic hose that takes the purged fluid to a milk bottle. Then you put 6 quarts of ATF+4 in the transaxle and start the motor and run a couple of quarts into the bottle. Then repeat until the fluid is bright red and clear. What I noticed when I did the job is that the fluid was a dull murky red color and that there were a lot of metal flakes in the bottom of the pan especially around the magnet. My guess is that at 60,000 miles the magnet would be so loaded up that it would no longer be effective. Based on those observations I decided to keep up the 25,000 mile plan even though everyone was laughing at me for wasting my time under the car on that creepy crawler getting dirt under my fingernails.

Everybody I knew that had a Chrysler minivan back then only got around 75K miles before they had to go in for the dreaded $2,500 transmission job. Most of them got around $3,000 in trade when they traded in their vans which were in very good condition in 2001 or 2002 for an SUV. They told me that the transaxle on their van had failed forcing them to trade it in and that my minivan would soon be a "Goner".

Eleven years have passed. I had to trade in the minivan last week because the hinge on the passenger door got rusted to the point that the door would no longer close. At the time I turned it in, the motor was still running smooth as silk and the transaxle (which I did have to replace at 165,000 miles because it was leaking in the front seal) was not leaking and shifting perfectly. I am convinced that if it had not gotten rusty at the hinge, it would have gone another 100,000 miles. I traded it in on a 2005 Grand Caravan SXT with 25,000 miles for a total of $17,000 tax and all. (It had a sticker of $27,000 new but they depreciate a lot because minivans are not hot on the market and everybody knows that the transaxles are prone to failure.) All of my friends who traded in their vans for SUVs 5 or 6 years ago are now getting ready to trade in again for a new model.
It is interesting to note that the owner's manual for the 2005 Grand Caravan still says that you don't have to change your transaxle fluid at all unless it is operated under severe conditions and then only at 60,000 mile intervals. I am sticking with the 25,000 mile plan because the trsansaxle is essentially the same as the one in my 95 and I expect to see the same metal flakes and murky fluid at each change.

The main point is that everybody has an axe to grind.

The guy who wrote the article has to make a living writing articles that folks will read and what is more readable than an article about a conspiracy to "flush" the public of its hard earned money through shady practices?

Chrysler Corporation has to sell vehicles and it is a lot easier to sell a vehicle when you claim that it requires very little maintenance. They also want to sell remanufactured transaxles and it is a lot harder to sell them when folks take care of what their vehicles. So they tell you that you have bought "fluid for life" transaxle. They just don't define what "life" is. It is a bad strategy because folks who don't know anything about cars get the perception that their products are unreliable when that's not the case.

The way I see it is that I have been able to avoid 1 depreciation cycle by taking care of my van and that the amount of the depreciation I have avoided is around $20,000. The cost of that maintenance has been about $60.00 every 25,000 miles ($40 per transaxle service, $3.00 for Power steering fluid $3.00 for brake fluid and $10.00 for coolant. I havent needed a fancy machine to do any of those things. Multiply that number times 10 and you get $600. Add $300 to that because you are doing oil changes at 5k instead of 7.5k and you get a total of around $1,000 for all of that extra maintenance. Subtract the $1,000 for the extra maintenance from the $20,000 that went to money heaven and you end up saving around $19,000.
If you are paying someone to do that work then multiply the $1,000 by 3 or 4 and you still end up with a pretty good amount of money saved.

tvpierce · #10 04-18-2006, 12:55 PM

My friend's Toyota Celica (mid-90s... can't remember exact year) called for conventional oil, with a change interval of 7500 miles.

lkchris · #11 04-18-2006, 02:41 PM

Quote:

Originally Posted by Hatterasguy

I don't agree with him on the brake fluid part though, it should be changed every 1-2 years.

Then you should read the following:
http://www.babcox.com/editorial/bf/bf50412.htm

lkchris · #12 04-18-2006, 02:44 PM

Quote:

Originally Posted by Hatterasguy

Since most cars these days use synthetic oil 5k miles is a good conservative number to change it. Actualy most manuals spec 7,500 miles for "severe duty".

Actually, the interval on new Mercedes is 13K miles.

cudaspaz · #13 04-18-2006, 04:40 PM

being a former dealer tech, i think mercedes flushes were not excessive and really don't apply much to that article.

Hatterasguy · #14 04-18-2006, 05:29 PM

Quote:

Originally Posted by lkchris

Then you should read the following:
http://www.babcox.com/editorial/bf/bf50412.htm

Very interesting.

I'll stick to what MB says in my manual "flush brake fluid once a year". It costs me a whole $10.

The European car makers run oil changes longer, for example BMW is 10k miles.

The new MB's are 13k miles or 1 year, provided you use Mobil 1 0w40 and a fleece filter.

rchase · #15 04-20-2006, 04:22 AM

I don't mind bringing my car in for service and having everything changed once a year. Personally I think its a great idea and would rather pay a little extra in labor and fluids to provide the car its "optimal" working conditions. I even name and talk to my cars because they may be machines but they are very much part of my family. Im willing to do everything in my power to make my cars last as long as they can within reason.

I don't however like to be blatantly lied to and mislead by an untrained "mechanic/salesman" in an oil change place. His motivation is not for the superior service of my vehicle his motivation is to make his employer as much money as he can. A lot of these places prey on people who are underinformed on how a vehicle works. They have no specific training on any vehicles and don't understand how they work. You can have fun with them with a 5cyl Volvo engine or with a 5cyl Mercedes turbo diesel because most are only familiar with the 4, 6, 8 engine configurations. Many cars require many different kinds of fluid requirements which are not satisfied because of the shop's lack of training and lack of information resources. Your doing yourself a great disservice letting any untrained service personell near your car without supervising them.

I personally think that knowing how a car works should be part of the drivers licencing testing. If people knew more about their vehicles they would be more safe on the roads and realize what service can and cannot be put off preventing accidents and stalled cars on the expressway. Part of getting my Pilot's licence required me to understand how many of the navigational and powerplant features on my aircraft actually worked and what I could do with an inflight failure. I always make it a point to learn as much as I can about any vehicle I own for safteys sake and to provide it the best and most cost effective service program I can.

I just bought a W-140 and think I finally have met my match for vehicle complexity. I have a technical background (Unix Systems Administrator) and suddenly have realized that there will be a rather steep learning curve before I understand the w-140.