How to change oil and how to avoid a wallet flush

mazda
oil
mazda3

#1

Dear Tom and Ray,

I?ve listen to your show for almost 20 years and want you to settle a disagreement with me and my older brother. I also have a suggestion to avoid the wallet flush at the dealer.



My brother and I have different methods for draining the engine oil during an oil change. My brother uses the traditional method of draining the oil after the car has been run for a while and the engine and oil are warm. The oil is thinner and drains faster.



I wait until the next day when the engine is cold and since the oil drains slower, I let it drain for 45 minutes to an hour. Pull the plug and oil filter, clean your hands and go watch football or baseball of while, come back, re-install the plug , add a new filter and oil. There are two advantages to this method. A, The oil has had all night to drain down into the crank case. II, the engine, oil and exhaust are cold. I don?t worry about burning my hands or arms on anything. Several cars I?ve owned had the oil filter next to the exhaust manifold or other hot piece of metal.



So which method is better or are they both correct?



My sister-in-law found a way to avoid the dealer?s wallet flush when getter her car serviced. When the sales manager in the shop says she needs a fuel inject flush, engine flush, break line flush and wallet flush, she asks ?Is this part of Toyota?s recommended service? It isn?t part of the service listed in the manual?? The salesman then stops suggesting extra work.


#2

No T&R here…both methods will yield identical results.


#3

Just depends on how patient you are for your oil to drain out. Otherwise there is no dif.


#4

I have drained oil both ways. Very little, if any, difference.


#5

Either method is fine but I do mine when cold for the reasons you mentioned.

A flush does not always mean a ripoff either. The owners manuals are not always correct as to what’s best for your vehicle. The owners manuals are put together by the marketing dept. who want you to think you car is near maintenance free.

A flush of a particular fluid on a 1 year old car with 10k miles on it is likely a gouging.
The same on a 3 year old, 40k miles car may not be at all.

(And these “salesmen” as you refer to them are likely the service writers. Service writers have little mechanical aptitude for the most part. Their job is to fill in the blanks on the paper and converse with the customer; even if they don’t have a clue as to what’s going on.)


#6

I also usually do it in the morning, but it really doesn’t matter. Either way is great, as long as you actually do it and change the filter each time as well.

But in winter I warm the engine up a bit.

In my case doing it while it’s cold has the added advantage of allowing me to “play” under the car, pushing and pulling on anything that looks suspicious, without worryng about a hot part. Looking around is the best way to spot a problem before it becomes serious.


#7

I usually do mine right after getting home, when it is fully hot. I run it up on the ramps, shut it off, then get my tools, drain tub, rags, fermented malt beverage, etc…Then I remove the dipstick and drain plug and let it drain for about 10 minutes or so. By that time, the exhaust components are mostly cooled down, and the oil filter isn’t terribly hot. I do think it drains better when hot. When it is 90+ degrees outside, I usually give it an extra half hour or so to cool after putting it on the ramps.

In doing this for 20+ years (probably 110-120 oil changes), I have gotten to where I could do it in my Armani tux if I had one.


#8

The warm drain works better for heavier oils, ie. the straight 30W in the lawn mower. Newer cars using 5W or 0W oils it makes little to no difference. If you are running 20W-50 perhaps the warm drain would be better.


#9

Either method is fine. Both methods drain most of the oil, which is all you should really care about.

Personally, I think both you and your friend have too much time on your hands. Perhaps your time would be better spent arguing about who to blame for the Van Halen split-up.


#10

I think both methods are satisfactory; however, I see a potential problem with your method.

If you’re going to leave the car unattended with the oil out of it, there is the potential for a forgetful owner (or wife/GF/friend of owner) to “fire up” the car, thinking it is in drivable condition, potentially causing damage.

Any time I drain oil/disconnect fuel lines, or otherwise make a car non-operable for an extended period of time, I tape up a “NO OIL” or other sign in a conspicuous location.

This is also why I like to complete a repair in one step, if possible. Doing a “partial” brake job, going to bed, then finishing the next day just seems like an opportunity for omissions to creep in.


#11

Wait about a half hour after you shut off the engine and then change the oil and filter, allowing the crankcase to drain for a few minutes until the oil stream becomes a drip. That way, the oil will still be warm and you don’t need to change into dirty work clothes twice.