Transmission temperature?

#31

kassim503 wrote:So I added some fluid and I had a brain fart and forgot i was filling fluid, i poured 3/4 a quart in. Is the fluid going to foam?

I would try to keep it within the recommended levels. I did the same thing last month; didn't realize that it takes probably less than a pint to go from the low level to high. Used the Mityvac to pull out the excess. That Mityvac is one of my favorite chichi tools. If you don't have a Mityvac or similar, you could drain some excess fluid by loosening one of the hoseclamps on the hose fitting at the pressure side of the cooler, but then you'd have to clean up the mess afterward. On your car that area looks so clean!

#32

I guess your right, I really shouldnt run that much fluid, its probably asking for trouble. I think I have enough hose in there to actually get the hose to be out of the car so I could point it down into a bottle or something so hopefully, no mess

If the car pees everywhere I have a nice big bag of kitty litter to soak it up

Carimbo, when you said clean, did you mean rust free or dirt free?

It took me several months to grind all the rust off my car, then slap some bondo on top of that, hastily sand it, and then send it off for the maaco $299 paint job.

I know this is off topic but anybody have any experience with maaco? Anybody feel their paint is a bit "softer" or whatever, and it scratches eaiser? For example, if you put a cup of coffee on the roof of your car, itll make a ring thats engraved into the car, or if you put something on your car and take it off the dirt is rubbed in there much worse than normal paint.

#33

Checked when hot: personally, I'm OK with up to 5/8" over the "full hot" mark. Beyond that, I get nervous.

I have one of the larger Mityvac units that works well for snaking down the fill tube and sucking out excess.

#34

It sure looks like it beats trying to syphon ATF out through the dipstick. In my experience that takes forever!
Plus a very sore mouth.
Ray Mac

#35

This morning I tried siphoning it out of the dipstick tube, all I succeded in is getting a mouthful of fluid in my mouth. Then I pulled a cooler line and put the line in a bottle, and ran the car so itll fill the bottle, good idea when you put the outlet tube in the bottle instead of the inlet so there was fluid everywhere. Good part about it though is I must of dumped 2-3 quarts out so thats half a transmission fluid change right there, and the oil that came out was pretty dark so I guess this is a good thing and not a bad thing.

Trans fluid wont ruin my paint right?

#36

The 83 L4N71B trans is supposed to require 7-3/8 quarts to fill dry.

No, ATF won't damage your paint . . . unless your paint is Maaco paint

#37

Al, you where joking about the paint getting removed by atf right?

My car got egged today and while repainting several parts of my car I noticed there was paint missing from a part that was covered by atf. Well eggs where in the general vicinity so im curious if the atf could of played a part in this.

#38

Yeah, I was joking. ATF should have zero effect on paints.

Brake fluid will remove laquer paints and apparently some grille paint on Dodge grilles (they have an OEM sticker on the top of the grille about this). I've had egg damage paint, yes.

#39

Brake fluid is pretty rough on paints, the metal under my brake master cyl is pretty rusty due to a leaky one.

On the other hand there was a eye witness along with a couple of other pissed off people that got their car egged and damaged so sombody filed a police report and I want to jump in on that.... any chance I can get some money from this? I want to repaint the nasty spot thats made out of touch up spray thats on my car.

#40

I am planning on changing the transmission cooler setup to something that is a bit better, and since I dont have the factory trans cooler/ heater. Should I install a oil thermostat into the system?

What are the problems that I could possibly encounter if I run temperatures between 80-100 for about a whole week at a time? There is usually a once a week trip that the whole car is gonna warm up on. Im running about 130-140 now, and I never really gave transmission temperature thought, but I want this tranny to stick around for a while.

The downside of the oil thermostat idea is not only is it gonna make the whole job take longer, cause im running lines this time, not draping hoses everywhere. Also the 180 degrees that most oil t-stats open at is too hot for me, and lastly, it adds to complication and its just one more thing that can break.

I dont notice any shifting lag when the transmission is cold, talk about a nicely designed transmission.

#41

If you're running a synthetic ATF, there may be no downside to the oil being too cool. Unlike engine oil that is constantly having water added to it as a combustion byproduct, ATF doesn't get significant external contamination, so you don't need to drive the water out of it: it doesn't have any.

The cheaper ATFs show a significant viscosity change from cold to "working temp" and could (evidently, not on your trans) affect shift timing and more often shift quality.

[Side note: the old Dual Coupling HydraMatics in the 50's had a temperature compensator bimetal doodad to alter the line pressure or shift point or something, when the trans was cold. It was needed!]

Another factor with non-synth ATF is drag and fuel economy: cold oil is (by and large) more expensive to pump and sluice (in terms of HP used) than warm/hot oil. This is much less of a factor with synth oils.

HTH

#42

Yet another reason to run synthetics!

#43

Where electronic automatics are concerned, I am most familiar with post 2000 Toyota. The transmission ECM does monitor ATF temperature and adjusts line pressure. Reasons given are compensation for friction coefficient increase as the fluid thins with heat and MPG. Toyota started using a unique T-IV fluid formulation in '01 or '02, starting in some Lexus models. This stuff is also known for turning black rather soon compared to Dexron. I don't know if T-IV is synthetic.

Because of viscus drag, MPG, and shift quality, I would not run an oil-to-air cooler without a thermostat as a minimum ATF temperature could not be maintained. If the (in radiator) OEM heat exchanger is holding ATF temperature below 160* then your application needs no more capacity. Remember, prolonged over cooled ATF also costs fuel economy.

#44

no, the factory heat exchanger went when I bought a new universal rad with no a/t hookups, im running a oil-air cooler from some Mitsubishi now, it holds temperature during light driving, but once u drive for prolonged periods without any transmission lockup, the trans temp gets over 200-220 easy. I am aiming for a 200 degree ceiling on temperature, even if I sat there smoking the tires for hours. I like having lots and lots and lots of extra reserve cooling in case I have to floor it or somebody drives my car thats not me, the car is there to handle the beating. I think ill run a oil-temp thermostat, I think that if the trans was up to temperature, id get better fuel economy, and also the transmission would have less of a chance of snapping something because the internals are slightly more flexible due to it being hot.

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Transmission temperature?

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