1999 SL2 - Automatic transmission problem?

[Brian]

Hi there,

Just looking for an opinion on a possible transmission problem on my
1999 SL2 automatic. I'm hoping this isn't the valve box problem I've
found so much about on Google.

57000 miles on the car, was just in for service a month (1000 miles)
ago, where they told me I had leaking transmission fluid and replaced
the torque axis mount, changed trans fluid and filter, and replaced
the serpentine drive belt.

So Saturday, after making about a 60 mile round trip earlier in the
day with no trouble, my problem started up. Had the car parked, on an
incline with the emergency brake on. Started the car up with no
trouble, but heard a loud bang/rumble sound upon shifting to reverse,
and a smaller one on shifting back to drive.

After that, driving the 8 miles home, I noticed that the car was
really sticking/jerking when it would upshift, occasionally making
another loud rumble, and then would also do the same thing to a lesser
extent on slowing down to a stop.

It's doing the same thing today. So my thought is that I will drive
it in to work tomorrow morning (1.5mi) and then to the dealership at
lunch and have them take a look at it. I'd just really like to hear
what else it might be. I may have left my headlights on for about 2
hours after coming back from the 60mi roundtrip, but that shouldn't be
enough to drain the battery. Would it be worth taking it for a drive
on the interstate to make sure the battery has a chance to charge back
up, before heading to the (likely gouging) dealer?

Should also mention - this is Connecticut and this is August. It's
very hot and humid. I can only imagine the kind of expansion going on
in the metal parts.

Any suggestions would be greatly appreciated. Thanks!

[Email cc's of responses also appreciated]

 

[Kirk Kohnen]

CHECK YOUR
ALTERNATOR!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Now, let me answer the question that you're asking yourself: "Why the hell
is this idiot telling me to check my alternator, when I'm having problems
with my transmission?"

Good question.

The Saturn alternators are prone to failure. Heat does them in. You stated
that it is very hot and humid. Also, you have about the right number of
miles for your alternator to fail (57,000 miles) on a Saturn. In fact, I'd
say you're past due...

When the alternator is failing, it puts out lower and lower voltages. In
addition, it puts some really strange crap onto the main power line of the
car. (When a diode shorts, it puts very strong voltage pulses.) These pulses
confuse the computers of the car.

Your transmission is entirely computer controlled. The bad voltage on the
computer input confuses it.

I would check the alternator and battery. Replacing your alternator and
battery may very well eliminate your alternator problem.

Several times when my wife's 97 SL2 has needed a new alternator, bad
transmission performance was the first indication.

Hi there,

Just looking for an opinion on a possible transmission problem on my
1999 SL2 automatic. I'm hoping this isn't the valve box problem I've
found so much about on Google.

57000 miles on the car, was just in for service a month (1000 miles)
ago, where they told me I had leaking transmission fluid and replaced
the torque axis mount, changed trans fluid and filter, and replaced
the serpentine drive belt.

So Saturday, after making about a 60 mile round trip earlier in the
day with no trouble, my problem started up. Had the car parked, on an
incline with the emergency brake on. Started the car up with no
trouble, but heard a loud bang/rumble sound upon shifting to reverse,
and a smaller one on shifting back to drive.

After that, driving the 8 miles home, I noticed that the car was
really sticking/jerking when it would upshift, occasionally making
another loud rumble, and then would also do the same thing to a lesser
extent on slowing down to a stop.

It's doing the same thing today. So my thought is that I will drive
it in to work tomorrow morning (1.5mi) and then to the dealership at
lunch and have them take a look at it. I'd just really like to hear
what else it might be. I may have left my headlights on for about 2
hours after coming back from the 60mi roundtrip, but that shouldn't be
enough to drain the battery. Would it be worth taking it for a drive
on the interstate to make sure the battery has a chance to charge back
up, before heading to the (likely gouging) dealer?

Should also mention - this is Connecticut and this is August. It's
very hot and humid. I can only imagine the kind of expansion going on
in the metal parts.

Any suggestions would be greatly appreciated. Thanks!

[Email cc's of responses also appreciated]

 

[Brian]

CHECK YOUR
ALTERNATOR!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Now, let me answer the question that you're asking yourself: "Why the hell
is this idiot telling me to check my alternator, when I'm having problems
with my transmission?"

Good question.

The Saturn alternators are prone to failure. Heat does them in. You stated
that it is very hot and humid. Also, you have about the right number of
miles for your alternator to fail (57,000 miles) on a Saturn. In fact, I'd
say you're past due...

When the alternator is failing, it puts out lower and lower voltages. In
addition, it puts some really strange crap onto the main power line of the
car. (When a diode shorts, it puts very strong voltage pulses.) These pulses
confuse the computers of the car.

Your transmission is entirely computer controlled. The bad voltage on the
computer input confuses it.

I would check the alternator and battery. Replacing your alternator and
battery may very well eliminate your alternator problem.

Several times when my wife's 97 SL2 has needed a new alternator, bad
transmission performance was the first indication.

Thank you very much for the advice. I will also check on this once I
have the car back. If it does turn out to be the case (as opposed to
the transmission solenoid Saturn blamed it on - which sure could be a
symptom of the alternator) then I will be definitely be having a chat
with some people at the home office and making plenty of noise about
the local dealership.

I really screwed up by not keeping my warranty paperwork with me
today, instead leaving it in the glovebox of the car, but I really
feel like most of this should be covered (I can understand them not
wanting to cover it if I kept driving on this for a while) under the
36/36 warranty (my lease that I bought is suddenly a "used"). But
it's easier to just pay them and get the car back -- hopefully people
have had luck getting compensation back from Saturn corporate after
things like that.

But remembering the exclusion list on that warranty sheet, I have a
feeling it was a waste of $1200.

Thanks again for your help.