Tire advice and outcome

Thanks for those who posted tire advice concerning my 2000 Dakota. I
went back to the stock size in an all season passenger car tire but
not without some difficulty.

At Wallyworld, I told the service writer the size. I had a copy of
the list and so did she, and she turned to the truck tire page.

"I don't want truck tires (taking the advice here). I want passenger
car tires."

"I'm not looking at truck tires (the page was captioned 'light truck
and SUV') I'm looking at.... .... .... tire tires."

"Well the ones I want are on the first page. (Pointing on my copy to
some Uniroyal AS tires). Turn the white walls in."


So after sorting that out, I looked at the authorization ticket and it
said 5W30 for the oil change (apparently computer generated based on
the vehicle info) and I said I wanted 10W30.

After maybe half an hour, I got paged to the service department where
the following conversation occured with the mechanic.

"Do you know the size you've asked for isn't the same as what's on the
truck?"

"Yea, but the size I've picked is the right size. Its what's on the
sticker, same size as the spare. The previous owner put on oversize
tires. Don't know why."

"OK. Just thought I'd better check. It did look like it was sitting
a bit high". (Now, how high its sits is a real good method of
determining the right size tires, don't you think?)

So I went and wandered back out into the store. Then I got paged
again. Had this coversation with the service writer and manager.

Service writer

"We only have three of those tires."

Manager interjecting while passing through

"The computer says we have four, but one is mislabeled as a 75 when
its really a 70. A 70 is shorter."

Me

"What else do you have?"

The service writer flipped to the LT/SUV page, indentifed some gypo
brand WL tire in a P size but with an LT tread pattern and checked
inventory on the computer. Looking over her shoulder, I saw inventory
of "1", so I didn't have to argue that point with her (fortunately,
after the earlier discrepancy, it didn't occur to her that computer
inventory might be wrong on this one too!).

So she went back to page one and suggested a Goodyear something or
other (silence on my part, remembering the advice here) and then went
to the inventory screen... which fortunately for me showed 3 in stock,
so I figured I was safe.

Service writer

"Let me call another store and see if I can get you a 4th tire. If
they have one we'll go get it right away."

So it turned out the other store had enough to make a set of 4 on both
the Uniroyal and the Goodyear.

Service writer

"They have both. Which do you want?"

Me (seems real obvious)

"My first choice."

OK. That's done, so I wandered back out into the store again, for a
long time this time, and, wondering if this was all manipulation to
get me to buy something before they'd cut my truck loose, found an Old
Blue Eyes CD to give as a Christmas gift to a relative old enough to
remember when Old Blue Eyes was a new and upcoming singer, plus Jo Dee
Messina's Greatest Hits for me. (Fervent hope I'd done what was needed
to get my truck finished.)

Finally, I was paged that the truck was ready.

Service writer

"The sticker on the oil cap says 5W30. Y'know, its best to use what
they say. I know someone who used 10W40 and it gummed up her engine
and ruined it."

At this point, I wasn't particularly upset, although I was 3 hours
into the deal. After all, they did sell me what I wanted (except for
the oil) and they made a good effort to get the tires I wanted (and
most fortunately, did so quckly within the context of the capabilities
of doing so.)

So overall I'm happy. After all, had I gone to a real tire store,
when they found out one of the 4 75s on the computer was actually a
mislabeled 70, those "professionals" would have tried to sell me a
whole set of 70s based on the pitch that a wider tire puts more rubber
on the road. Blessed are the true amatuers!

> So after sorting that out, I looked at the authorization ticket and it
> said 5W30 for the oil change (apparently computer generated based on
> the vehicle info) and I said I wanted 10W30.

(snip)

> "The sticker on the oil cap says 5W30. Y'know, its best to use what
> they say. I know someone who used 10W40 and it gummed up her engine
> and ruined it."
>
> At this point, I wasn't particularly upset, although I was 3 hours
> into the deal. After all, they did sell me what I wanted (except for
> the oil)

Thicker oil protects the engine better, but the default suggestion is almost
always 5W30 or even 0W30 (ZEROW30). This is because thinner oil offers
slightly better fuel economy. So it MAKES SENSE for a car manufacturer to
suggest lighter oil be used. Most people don't keep their cars (even if
they bought it USED) long enough to wear out the engine. If lighter oil is
used, the car manufacturer can claim that their cars get better fuel
economy. But even the car manufacturers contradict themselves on
recommended viscosity for oil. The oil cap on my car specifies 5W30. The
only time 5W30 has ever been in the engine is (possibly) when the engine
left the factory. But IN THE OFFICIAL SERVICE MANUAL for that SAME EXACT
VEHICLE, 10W40 is recommended. In fact, it specifically states that all
viscosity levels from (5W30) on up to (20W50) CAN be used. Yes, 20W50. Of
course, it has a chart showing outside temperature relating to various
viscosity levels of oil. Basically, the hotter the temperature, the thicker
the oil should be used. But if you study the chart carefully, you will see
that either 10W30 or 10W40 can be used safely year-round. This is on a car
with "5W30" on the oil cap.

Unfortunately, the people working at quick change oil shops aren't the
brightest bulbs on the tree. They see the computer recommend 5W30 or read
it on the oil cap, and think that a customer must be NUTS to want to put
thicker oil in their car to protect the engine better. There's no point in
mentioning the Service Manual recommendations, either. The Oil Cap MUST
know more than the people who wrote the Service Manual, right?

I'd be highly skeptical of the claim that simply changing from 5W30 to 10W40
caused an engine to get gummed up and ruined. I would expect that changing
from 5W30 to 10W40 might (at worst) significantly lower that vehicle's fuel
economy. -Dave

On Tue, 6 Dec 2005 09:44:23 -0500, "Mike T." >
wrote:


>Thicker oil protects the engine better, but the default suggestion is almost
>always 5W30 or even 0W30 (ZEROW30). This is because thinner oil offers
>slightly better fuel economy. So it MAKES SENSE for a car manufacturer to
>suggest lighter oil be used.


Hmmm... only the 4.7, of the 4 engines offered in the 2000 Dakota,
carries a recommendation to use 5W30.


>Most people don't keep their cars (even if
>they bought it USED) long enough to wear out the engine.


Mopar people do.


>Unfortunately, the people working at quick change oil shops aren't the
>brightest bulbs on the tree.


What?!?! They all have their training certificates displayed! <G>


>They see the computer recommend 5W30 or read
>it on the oil cap, and think that a customer must be NUTS to want to put
>thicker oil in their car to protect the engine better. There's no point in
>mentioning the Service Manual recommendations, either. The Oil Cap MUST
>know more than the people who wrote the Service Manual, right?


Interestingly, I bought that oil cap as a replacement for the OEM cap
as part of the "cure" for the 4.7 filler neck condensation/milk
problem.


>I'd be highly skeptical of the claim that simply changing from 5W30 to 10W40
>caused an engine to get gummed up and ruined. I would expect that changing
>from 5W30 to 10W40 might (at worst) significantly lower that vehicle's fuel
>economy. -Dave


Are you sure you meant to say "highly skeptical"? That seems more
than a bit reserved considering the whole situation.

>>Thicker oil protects the engine better, but the default suggestion is
>>almost
>>always 5W30 or even 0W30 (ZEROW30). This is because thinner oil offers
>>slightly better fuel economy. So it MAKES SENSE for a car manufacturer to
>>suggest lighter oil be used.
>
>
> Hmmm... only the 4.7, of the 4 engines offered in the 2000 Dakota,
> carries a recommendation to use 5W30.
>
>

Pickups are gas hogs anyway, so thinning out the oil won't help much.
You'd probably find the manufacturing tolerances aren't ideal for thin oil
on the other three Dakota engines. I had a car that would use no oil at all
between fill-ups if I put 10W40 in it, but would use a little more than a
quart of 5W30 between oil changes. I'll bet that the brand new dakota
engines are probably the same way . . . they actually need the thicker oil.
Nothing wrong with that. -Dave

In article ews.net>, Mike T. wrote:

> Thicker oil protects the engine better, but the default suggestion is almost
> always 5W30 or even 0W30 (ZEROW30). This is because thinner oil offers
> slightly better fuel economy.

Or because the engine has some particularly small passages and
clearances. In that case a thicker oil is probably not a good idea.

> So it MAKES SENSE for a car manufacturer to suggest lighter oil be used.

CAFE also forces the issue.

On Tue, 06 Dec 2005 23:17:25 -0600,
(Brent P) wrote:


>> So it MAKES SENSE for a car manufacturer to suggest lighter oil be used.
>
>CAFE also forces the issue.


The owner's manual says 5W30 is preferred for temps up to 100 degrees
for the 4.7 because fuel economy will be better. It specifically says
that fuel economy is the reason.

Guess they didn't need any fuel mileage help with the 2.5, 3.9, and
5.9, all which give 10W30 as preferred and 5W30 as acceptable. Wierd
stuff. (Probably some double talk going on here.)

On Fri, 09 Dec 2005 08:52:29 -0500, edward ohare
> wrote:

>On Tue, 06 Dec 2005 23:17:25 -0600,
>(Brent P) wrote:
>
>
>>> So it MAKES SENSE for a car manufacturer to suggest lighter oil be used.
>>
>>CAFE also forces the issue.
>
>
>The owner's manual says 5W30 is preferred for temps up to 100 degrees
>for the 4.7 because fuel economy will be better. It specifically says
>that fuel economy is the reason.
>
>Guess they didn't need any fuel mileage help with the 2.5, 3.9, and
>5.9, all which give 10W30 as preferred and 5W30 as acceptable. Wierd
>stuff. (Probably some double talk going on here.)


Not just probably, and not just a bit.