Tranny fluid

[76bonanza]

When I check my transmission fluid. If the truck is cold I let it heat up in drive way when it comes to temp I slowly go thru gears and then check with motor running right on full. If I drive home from work park run it thru the gears then check it it reads way full which reading would you say is correct?

Thanks for your help.

[87 STEPPER]

I would say the second one your suppose to drive the truck untill it reaches op. temp.

And then park on a level surface and with it running and the trans in park check the fluid level.

Then make adjustments of the fluid level as necessary.

[Hoods69BadBowTie]

I think the second one would be more accurate. It needs to reach optimum tempature and then park it on level ground and check fluid. Correct if nesscary.
-Later

[76bonanza]

Ok one other question Then it is reading about a half inch over full will that hurt anything or should I not worry about it. It does have a slow leak not bad but annoying.

[Brad_Olson]

Originally Posted by 76bonanza

When I check my transmission fluid. If I drive home from work park run it thru the gears then check it it reads way full which reading would you say is correct?

How long of a drive is it? IIRC the recommendation is a drive long enough to get the fluid up to normal temp but after a longer drive (like 10 miles or more) there should be an interval of about 5 minutes between parking and checking. I wish I could remember where I read this...any chance you have an owner's or service manual to check?

Brad

[76bonanza]

It is more than 10 miles like 15. in the haynes it says start it let it warm to operating temp go thru the gears and check,it says nothing about driving it. Also when I check it after the 15 mile drive it is really hard to read splashy or sparadic on the stick not like when I let it just warm up in park then it is very thick and level on the stick.

[87 STEPPER]

I think this is getting a little out of hand as long as the fluid is HOT it is good and the vehicle is level when it is ck'd.

If it show's a 1/2" over the full mark like you said then drain it untill it is at the full mark or just under it.

Too much fluid will/can cause an overheating condition to exist and that will lead to a trans failure.

Just a side note i drive my truck 35 miles to work and i stop for fuel about 5 miles away form my work and at least once a month i'll ck my tranny fluid level and it's allways right at the full mark.

I do ck it after iv'e finished fueling so i guess the five min thing applys by default but i dont think it's necessary what is necessary is that it be running and on level groung.

[76bonanza]

stepper so you turn off fuel then start then check? I know you think this is out of hand but if i read it right after home from work no turning off it reads high. But if I do it like the manual says just heat it up in park then check it it reads full.

[87 STEPPER]

Yeah i pull in fuel up eng. off then fire it up and ck it and take off.

Iv'e never had any of my trucks do that it's possible that there is several types of ATF in your trans and they have differant heat expansion rates and causing that problem. But thats just a wild guess on my part.

[76bonanza]

I will try it like that drive home let it sit 5-10 minutes then fire it up and check it.

Thanks stepper.

[76bonanza]

I do think I am a little past full about 1/4to 1/2 inch it has dextron III-mercon fluid is this right. If it is high the only way to drain it is pull pan right? It already leaks think it would be ok to let it leak down to right amount? Sorry to continue the thread.

[Earl Filter]

You're not going to hurt it at 1/4 - 1/2 inch over. That's a half-quart over max. If it's more than a quart over (probably more like 2), then you might hurt it. By the way, if you do decide to drain, loosen the trans cooler line at the radiator (the feed line FROM the trans, should be the hotter of the two lines when vehicle is hot). Disconnect that line with the engine off, and get a hose that will slip over the end of the metal cooler line, so you can direct fluid into a bucket. When you start the truck, the transmission pump will pump the fluid out. Be careful, the fluid will come out pretty fast. You shouldn't have to run the truck more than 10-20 seconds, if that. Reconnect the cooler line, then check again. It would be easier to pump out more than necessary, then add a little to get it back where it should be. This is also the way to do a poor-man's tranny flush...just keep pumping out fluid on the cooler line end, while adding fluid to the dipstick tube. MUCH easier than dropping the pan.

[87 STEPPER]

You dont need to apologize about asking a question it's ok.

The dex/merc III is ok to use in your truck.

If you drain the tranny like eral said be carefull to get the right line caus if you dont you will have tranny fliud all over your eng compt. and if it hits a hot manifold it could catach on fire

Iv'e drained a tranny like that and i disconnected the coil wire and just cranked it a few times it wont take alot to drain the amount you want to.

[MylilBowTie]

Transmission fluid will expand when it heats up. That's why you are getting two different fluid levels when its cold then warmed up. I would drive it around long enough to get the transmission fluid warm like 5-10 minutes, park somewhere, leave it running, pull the dipstick wipe it off, lay it out of the way, get back in and run the gear selector thru the gears ending back in park, put the dipstick back in, pull it back out and check the level then. Running the transmission thru the gears fills up the valve body and other parts of the transmission with fluid and what is left over is the reserve in the pan that's what gets measured by the dipstick.

If remove the cooler line to get the excess fluid out remove the power wire going to the distributor. That is so the engine will not start. I would remove it at the radiator end with a rubber hose and clamp, running the hose into an empty milk jug. Then all you need to do is turn the ignition on and tap it a few times then check to see how much fluid came out in the milk jug. It really doesn't take much to get a lot of fluid out at all. I believe its the top line that you want to remove the for the transmission line, if I remember right its the pressure line and not the return line.

[76bonanza]

thanks for all your guys help looks like I am a little over seems like if I just drove it if I let it sit for about 10 minutes then fire it up and check it it is about 1/2 inch high since it leaks any way I think I will just let it leak down to full.