Dex

iTrader: (5)

So does the transmission shift more on the highway or on in the city?
Cruising in the city last for what 100 yards? So it shifts through 4 gears just to come back to first while never making it over 2000rpm unless your doing something crazy.
Now i might as well make this clear city driving is CONSTANT stop and go traffic not cruising for 30 minutes
So explain to us how automatic transmission fluid goes bad?
I'm not trying to be a dick just get good info out there. We all know the internet is full of bad info. Before you jump my **** i am an ASE certified mechanic that went to Lincoln Tech Just for reference

Thorny

iTrader: (14)

Of course you're going to shift more in the city, but I'll bet that most of the time you shift into OD in traffic you're under deceleration. Your transmission doesn't shift through all 4 gears unless your speed and throttle position dictate it. According to the stock tune on a '99Z the slowest speed that will get you shifted into OD under acceleration is 24mph, and thats at 6% throttle. At 25% throttle the speed is 43mph. These are the settings straight from the factory tune with fuel economy being the biggest concern. Deceleration in OD LOWERS transmission output speed as well as engine speed, which makes a huge difference in fuel economy, and I really fail to see how that could possibly cause more wear.

Automatic transmission fluid goes bad due to heat OR oxidation. There may be many sources for the heat, but I can assure you that it's not from shifting into OD at low speed, uless your pulling a boat perhaps. The computer knows when you need to shift and will adjust shifting patterns if the trans gets too hot if it needs to. If your trans is getting hot from shifting into OD, you've got other serious problems with your transmission or torque converter. The only times I would EVER consider not using OD in an auto would be while pulling a heavy object at less than interstate speeds, or while driving in mountain terrain when I would use engine braking to help keep my brakes cool.

It seems like you are saying that shifting into OD at city speeds causes an unacceptable rise in trans temp which in turn decreases fluid life. If you could explain that to me I'd appreciate it, but I doubt you could find any evidence to back it up. The car is supposed to shift into OD, even at city speeds. Keeping it from doing so does not save wear and lowers fuel economy. http://www.fueleconomy.gov/feg/fe_test_schedules.shtml. This is what the government considers city driving. Far from 100 yards at a time. Not using OD in this type of driving is wasteful and causes increased engine wear.

RPM WS6

iTrader: (3)

I would respond to your post, but there is no need. Thorny has already perfectly summed up exactly what I would have said in his post:

Dex

iTrader: (5)

You guys do whatever you want. No longer worth trying to explain. You guys miss the whole point i was trying to make so nevermind.

KENS_SS_4

ericn99....I think I here your Mommy calling!

This is newbie tech. Not I'm too lazy to search or read stickies or as I mentioned your owners manual. Operating the gear selector is not a tech question. It is covered in the owners manual. Tech would be "Why use OD in the city" for example.

My answer was called for. It was not a flame, it was an admonishment.

It makes no difference whether you are in Sweden or anyplace else. We assume you have the basics, were the key goes, how to adjust the seat and of course how to operate the gear selector. All things easily looked up, NOT ASKED!

IMHO

Thorny

iTrader: (14)

Boy, you really are an *******. You must be illiterate too because his thread title was "Overdrive for city?", not "How do I operate my gear selector?". Your attitude is pathetic and doesn't belong in a tech forum any more than a "stupid" question does, so please STFU and skip over threads that irritate you.